Theory of mind
Encyclopedia
Theory of mind is the ability to attribute mental states—belief
s, intents
, desires
, pretending
, knowledge
, etc.—to oneself and others and to understand that others have beliefs, desires and intentions that are different from one's own. Though there are philosophical
approaches to issues raised in such discussions, theory of mind
as such is distinct from the philosophy of mind
.
insofar as the mind is not directly observable. The presumption that others have a mind is termed a theory of mind because each human can only intuit the existence of his or her own mind through introspection, and no one has direct access to the mind of another. It is typically assumed that others have minds by analogy with one's own, and based on the reciprocal nature of social interaction, as observed in joint attention, the functional use of language, and understanding of others' emotions and actions. Having a theory of mind allows one to attribute thoughts, desires, and intentions to others, to predict or explain their actions, and to posit their intentions. As originally defined, it enables one to understand that mental states can be the cause of—and thus be used to explain and predict—others’ behavior. Being able to attribute mental states to others and understanding them as causes of behavior implies, in part, that one must be able to conceive of the mind as a “generator of representations”. If a person does not have a complete theory of mind it may be a sign of cognitive or developmental impairment.
Theory of mind appears to be an innate potential ability in humans, but one requiring social and other experience over many years to bring to fruition. Different people may develop more, or less, effective theories of mind. Empathy
is a related concept, meaning experientially recognizing and understanding the states of mind, including beliefs, desires and particularly emotions of others, often characterized as the ability to "put oneself into another's shoes." Recent neuro ethological
studies of animal behaviour, suggest even rodents may exhibit ethical or empathic abilities. Neo-Piagetian theories of cognitive development
maintain that theory of mind is a byproduct of a broader hypercognitive ability of the human mind to register, monitor, and represent its own functioning.
Research on theory of mind in a number of different populations (human and animal, adults and children, normally- and atypically-developing) has grown rapidly in the almost 30 years since Premack
and Woodruff's paper, "Does the chimpanzee have a theory of mind?", as have the theories of theory of mind. The emerging field of social neuroscience
has also begun to address this debate, by imaging humans while performing tasks demanding the understanding of an intention, belief or other mental state.
An alternative account of theory of mind (ToM) is given within operant psychology and provides significant empirical evidence for a functional account of both perspective taking and empathy. The most developed operant approach is founded on research on derived relational responding and is subsumed within what is called, "Relational Frame Theory." According to this view empathy and perspective taking comprise a complex set of derived relational abilities based on learning to discriminate and verbally respond to ever more complex relations between self, others, place, and time, and the transformation of function through established relations.
On the other hand, simulation theory suggests ToM is not, at its core, theoretical. Two kinds of simulationism have been proposed. One version (Alvin Goldman
's) emphasizes that one must recognize one's own mental states before ascribing mental states to others by simulation. The second version of simulation theory proposes that each person comes to know his or her own and others' minds through what Robert Gordon names a logical "ascent routine" which answers questions about mental states by re-phrasing the question as a metaphysical one. For example, if Zoe asks Pam, "Do you think that dog wants to play with you?", Pam would ask herself, "Does that dog want to play with me?" to determine her own response. She could equally well ask that to answer the question of what Zoe might think. Both hold that people generally understand one another by simulating being in the other's shoes.
One of the differences between the two theories that have influenced psychological consideration of ToM is that theory-theory describes ToM as a detached theoretical process that is an innate feature, whereas simulation theory portrays ToM as a kind of knowledge that allows one to form predictions of someone's mental states by putting oneself in the other person's shoes and simulating them. These theories continue to inform the definitions of theory of mind at the heart of scientific ToM investigation.
The philosophical roots of the Relational Frame Theory account of ToM arise from contextual psychology and refer to the study of organisms (both human and non-human) interacting in and with a historical and current situational context. It is an approach based on contextualism, a philosophy in which any event is interpreted as an ongoing act inseparable from its current and historical context and in which a radically functional approach to truth and meaning is adopted. As a variant of contextualism, RFT focuses on the construction of practical, scientific knowledge. This scientific form of contextual psychology is virtually synonymous with the philosophy of operant psychology.
states to others, as well as when in human ontogeny
and phylogeny
this ability
developed, has identified a number of precursory behaviors to a theory of mind.
Understanding attention, understanding of others' intentions, and imitative
experience with other people are hallmarks of a theory of mind which may be
observed early in the development of what will later become a full-fledged
theory. In studies with non-human animals and pre-verbal humans, in particular,
researchers look to these behaviors preferentially in making inferences about
mind.
Baron-Cohen identified the infant's understanding of attention in others, a social skill found by 7 to 9 months of age, as a "critical precursor" to the development of theory of mind. Understanding attention involves understanding that seeing can be directed selectively as attention, that the looker assesses the seen object as "of interest," and that seeing can induce beliefs. Attention can be directed and shared by the act of pointing, a joint attention behavior which requires taking into account another person's mental state, particularly whether the person notices an object or finds it of interest. Baron-Cohen speculates that the inclination to spontaneously reference an object in the world as of interest ("proto-declarative pointing") and to likewise appreciate the directed attention and interests of another may be the underlying motive behind all human communication.
Understanding of others' intentions is another critical precursor to understanding other minds because intentionality, or "aboutness", is a fundamental feature of mental states and events. The "intentional stance" has been defined by Dennett as an understanding that others' actions are goal-directed and arise from particular beliefs or desires. Both 2- and 3-year-old children could discriminate when an experimenter intentionally vs. accidentally marked a box as baited with stickers. Even earlier in ontogeny, Andrew N. Meltzoff
found that 18 month-old infants could perform target manipulations that adult experimenters attempted and failed, suggesting the infants could represent the object-manipulating behavior of adults as involving goals and intentions. While attribution of intention (the box-marking) and knowledge (false-belief tasks) is investigated in young humans and nonhuman animals to detect precursors to a theory of mind, Gagliardi et al. have pointed out that even adult humans do not always act in a way consistent with an attributional perspective. In the experiment, adult human subjects came to make choices about baited containers when guided by confederates who could not see (and therefore, not know) which container had been baited.
Recent research in developmental psychology suggests that the infant's ability to imitate others lies at the origins of both a theory of mind and other social-cognitive achievements like perspective-taking and empathy. According to Meltzoff, the infant's innate understanding that others are "like me" allows it to recognize the equivalence between the physical and mental states apparent in others and those felt by the self. For example, the infant uses his own experiences orienting his head/eyes toward an object of interest to understand the movements of others who turn toward an object, that is, that they will generally attend to objects of interest or significance. Some researchers in comparative disciplines have hesitated to put a too-ponderous weight on imitation as a critical precursor to advanced human social-cognitive skills like mentalizing and empathizing, especially if true imitation is no longer employed by adults. A test of imitation by Horowitz found that adult subjects imitated an experimenter demonstrating a novel task far less closely than children subjects did. Horowitz points out that the precise psychological state underlying imitation is unclear and cannot, by itself, be used to draw conclusions about the mental states of humans.
—(the German word Umwelt means "environment" or "surrounding world")—of the pre-verbal child.
In the most common version of the false-belief task (often called the ‘Sally-Anne’ task
), children are told or shown a story involving two characters. For example, the child is shown two dolls, Sally and Anne, who have a basket and a box, respectively. Sally also has a marble, which she places in her basket, and then leaves to take a walk. While she is out of the room, Anne takes the marble from the basket, eventually putting it in the box. Sally returns, and the child is then asked where Sally will look for the marble. The child passes the task if she answers that Sally will look in the basket, where she put the marble; the child fails the task if she answers that Sally will look in the box, where the child knows the marble is hidden, even though Sally cannot know, since she did not see it hidden there. In order to pass the task, the child must be able to understand that another’s mental representation of the situation is different from their own, and the child must be able to predict behavior based on that understanding. The results of research using false-belief tasks have been fairly consistent: most normally-developing children are unable to pass the tasks until around age four. (Notably, while most children, including those with Down syndrome
, are able to pass this test, in one study, 80% of children diagnosed with autism
were unable to do so.)
In order to make tasks more accessible for young children, non-human animals, and autistic individuals, theory of mind research has begun employing non-verbal paradigms. One category of tasks uses a preferential looking paradigm, with looking time as the dependent variable. For instance, Woodward found that 9-month-old infants preferred looking at behaviors performed by a human hand over those made by an inanimate hand-like object. Other paradigms look at rates of imitative behavior, the ability to replicate and complete unfinished goal-directed acts, and observations of rates of pretend play
. This means that individuals with a ToM impairment would have a hard time seeing things from any other perspective than their own. Individuals who experience a theory of mind deficit have difficulty determining the intentions of others, lack understanding of how their behavior affects others, and have a difficult time with social reciprocity. ToM deficits have been observed in people with autism spectrum
disorders, schizophrenics, persons under the influence of alcohol and narcotics, sleep-deprived persons, and persons who are experiencing severe emotional or physical pain.
, Alan M. Leslie
and Uta Frith
published research which suggested that children with autism
do not employ a theory of mind, and suggested that children with autism have particular difficulties with tasks requiring the child to understand another person's beliefs. These difficulties persist when children are matched for verbal skills (Happe, 1995, Child Development) and have been taken as a key feature of autism.
Many individuals classified as having autism have severe difficulty assigning mental states to others, and they seem to lack theory of mind capabilities. Researchers who study the relationship between autism and theory of mind attempt to explain the connection in a variety of ways. One account assumes that theory of mind plays a role in the attribution of mental states to others and in childhood pretend play. According to Leslie, theory of mind is the capacity to mentally represent thoughts, beliefs, and desires, regardless of whether or not the circumstances involved are real. This might explain why individuals with autism show extreme deficits in both theory of mind and pretend play. However, Hobson proposes a social-affective justification, which suggests that a person with autism deficits in theory of mind result from a distortion in understanding and responding to emotions. He suggests that typically developing human beings, unlike individuals with autism, are born with a set of skills (such as social referencing ability) which will later enable them to comprehend and react to other people’s feelings. Other scholars emphasize that autism involves a specific developmental delay, so that children with the impairment vary in their deficiencies, because they experience difficulty in different stages of growth. Very early setbacks can alter proper advancement of joint-attention behaviors, which may lead to a failure to form a full theory of mind.
It has been speculated that ToM exists on a continuum
as opposed to the traditional view of a concrete presence or absence. While some research has suggested that some autistic populations are unable to attribute mental states to others, recent evidence points to the possibility of coping mechanisms that facilitate a spectrum of mindful behavior.
research has supported this view, demonstrating specific brain regions consistently engaged during theory of mind tasks. Early PET
research on theory of mind, using verbal and pictorial story comprehension tasks, identified a set of regions including the medial prefrontal cortex
(mPFC), and area around posterior superior temporal sulcus
(pSTS), and sometimes precuneus
and amygdala
/temporopolar cortex
(reviewed in ). Subsequently, research on the neural basis of theory of mind has diversified, with separate lines of research focused on the understanding of beliefs, intentions, and more complex properties of minds such as psychological traits.
Studies from Rebecca Saxe
's lab at MIT, using a false belief versus false photograph task contrast aimed to isolate the mentalizing component of the false belief task, have very consistently found activation in mPFC, precuneus, and temporo-parietal junction (TPJ), right-lateralized. In particular, it has been proposed that the right TPJ (rTPJ) is selectively involved in representing the beliefs of others. However, some debate exists, as some scientists have noted that the same rTPJ region has been consistently activated during spatial reorienting of visual attention; Jean Decety
from the University of Chicago and Jason Mitchell from Harvard have thus proposed that the rTPJ subserves a more general function involved in both false belief understanding and attentional reorienting, rather than a mechanism specialized for social cognition. However, it is possible that the observation of overlapping regions for representing beliefs and attentional reorienting may simply be due to adjacent but distinct neuronal populations that code for each. The resolution of typical fMRI studies may not be good enough to show that distinct/adjacent neuronal populations code for each of these processes. In a study following Decety and Mitchell, Saxe and colleagues used higher-resolution fMRI and showed that the peak of activation for attentional reorienting is approximately 6-10mm above the peak for representing beliefs. Further corroborating that differing populations of neurons may code for each process, they found no similarity in the patterning of fMRI response across space.
Functional imaging has also been used to study the detection of mental state information in Heider-Simmel-esque animations of moving geometric shapes, which typical humans automatically perceive as social interactions laden with intention and emotion. Three studies found remarkably similar patterns of activation during the perception of such animations versus a random or deterministic motion control: mPFC, pSTS, fusiform face area
(FFA), and amygdala were selectively engaged during the ToM condition. Another study presented subjects with an animation of two dots moving with a parameterized degree of intentionality (quantifying the extent to which the dots chased each other), and found that pSTS activation correlated with this parameter.
A separate body of research has implicated the posterior superior temporal sulcus in the perception of intentionality in human action; this area is also involved in perceiving biological motion, including body, eye, mouth, and point-light display motion (reviewed in ). One study found increased pSTS activation while watching a human lift his hand versus having his hand pushed up by a piston (intentional versus unintentional action). Several studies have found increased pSTS activation when subjects perceive a human action that is incongruent with the action expected from the actor’s context and inferred intention: for instance, a human performing a reach-to-grasp motion on empty space next to an object, versus grasping the object; a human shifting eye gaze toward empty space next to a checkerboard target versus shifting gaze toward the target; an unladen human turning on a light with his knee, versus turning on a light with his knee while carrying a pile of books; and a walking human pausing as he passes behind a bookshelf, versus walking at a constant speed. In these studies, actions in the "congruent" case have a straightforward goal, and are easy to explain in terms of the actor’s intention; the incongruent actions, on the other hand, require further explanation (why would someone twist empty space next to a gear?), and apparently demand more processing in the STS. Note that this region is distinct from the temporo-parietal area activated during false belief tasks. Also note that pSTS activation in most of the above studies was largely right-lateralized, following the general trend in neuroimaging studies of social cognition and perception: also right-lateralized are the TPJ activation during false belief tasks, the STS response to biological motion, and the FFA response to faces.
Neuropsychological
evidence has provided support for neuroimaging results on the neural basis of theory of mind. A study with patients suffering from a lesion of the temporoparietal junction
of the brain (between the temporal lobe
and parietal lobe
) reported that they have difficulty with some theory of mind tasks. This shows that theory of mind abilities are associated with specific parts of the human brain. However, the fact that the medial prefrontal cortex and temporoparietal junction are necessary for theory of mind tasks does not imply that these regions are specific to that function. TPJ and mPFC may subserve more general functions necessary for ToM.
Research by Vittorio Gallese
, Luciano Fadiga and Giacomo Rizzolatti
(reviewed in ) has shown that some sensorimotor neuron
s, which are referred to as mirror neuron
s, first discovered in the premotor cortex
of rhesus monkeys, may be involved in action understanding. Single-electrode recording revealed that these neurons fired when a monkey performed an action and when the monkey viewed another agent carrying out the same task. Similarly, fMRI studies with human participants have shown brain regions (assumed to contain mirror neurons) are active when one person sees another person's goal-directed action. These data have led some authors to suggest that mirror neurons may provide the basis for theory of mind in the brain, and to support simulation theory of mind reading (see above).
However, there is also evidence against the link between mirror neurons and theory of mind. First, macaque monkeys
have mirror neurons but do not seem to have a 'human-like' capacity to understand theory of mind and belief. Second, fMRI studies of theory of mind typically report activation in the mPFC, temporal poles and TPJ or STS, but these brain areas are not part of the mirror neuron system. Some investigators, like developmental psychologist Andrew Meltzoff and neuroscientist Jean Decety
, believe that mirror neurons merely facilitate learning through imitation and may provide a precursor to the development of ToM. Others, like philosopher Shaun Gallagher
, suggest that mirror-neuron activation, on a number of counts, fails to meet the definition of simulation as proposed by the simulation theory of mindreading.
and high-functioning autism
(HFA). The first PET study of theory of mind in autism (also the first neuroimaging study using a task-induced activation paradigm in autism) employed a story comprehension task, replicating a prior study in normal individuals. This study found displaced and diminished mPFC activation in subjects with autism. However, because the study used only six subjects with autism, and because the spatial resolution of PET imaging is relatively poor, these results should be considered preliminary.
A subsequent fMRI study scanned normally developing adults and adults with HFA while performing a "reading the mind in the eyes" task—viewing a photo of a human’s eyes and choosing which of two adjectives better describes the person’s mental state, versus a gender discrimination control. The authors found activity in orbitofrontal cortex
, STS, and amygdala in normal subjects, and found no amygdala activation and abnormal STS activation in subjects with autism.
A more recent PET study looked at brain activity in individuals with HFA and Asperger syndrome while viewing Heider-Simmel animations (see above) versus a random motion control. In contrast to normally developing subjects, those with autism showed no STS or FFA activation, and significantly less mPFC and amygdala activation. Activity in extrastriate regions
V3 and LO was identical across the two groups, suggesting intact lower-level visual processing in the subjects with autism. The study also reported significantly less functional connectivity between STS and V3 in the autism group. Note, however, that decreased temporal correlation between activity in STS and V3 would be expected simply from the lack of an evoked response in STS to intent-laden animations in subjects with autism; a more informative analysis would be to compute functional connectivity after regressing out evoked responses from all time series.
A subsequent study, using the incongruent/congruent gaze shift paradigm described above, found that in high-functioning adults with autism, posterior STS (pSTS) activation was undifferentiated while watching a human shift gaze toward a target and toward adjacent empty space. The lack of additional STS processing in the incongruent state may suggest that these subjects fail to form an expectation of what the actor should do given contextual information, or that information about the violation of this expectation doesn’t reach STS; both explanations involve an impairment in the ability to link eye gaze shifts with intentional explanations. This study also found a significant anticorrelation between STS activation in the incongruent-congruent contrast and social subscale score on the Autism Diagnostic Interview-Revised
, but not scores on the other subscales.
In 2011, an fMRI study demonstrated that right temporoparietal junction
(rTPJ) of higher-functioning adults with autism was not selectively activated more for mentalizing judgments when compared to physical judgments about self and other. rTPJ selectivity for mentalizing was also related to individual variation on clinical measures of social impairment; individuals whose rTPJ was increasingly more active for mentalizing compared to physical judgments were less socially impaired, while those who showed little to no difference in response to mentalizing or physical judgments were the most socially impaired. This evidence builds on work in typical development that suggests rTPJ is critical for representing mental state information, irrespective of whether it is about oneself or others. It also points to an explanation at the neural level for the pervasive mind-blindness
difficulties in autism that are evident throughout the lifespan.
endowment and social
environment that allows them to acquire a theory of mind in the same way that human children do. This is a contentious issue because of the problem of inferring from animal behavior the existence of thinking
, of the existence of a concept of self
or self-awareness
, or of particular thoughts. One difficulty with non-human studies of ToM is the lack of sufficient numbers of naturalistic observation, giving insight into what the evolutionary pressures might be on a species' development of theory of mind.
Non-human research still has a major place in this field, however, and is especially useful in illuminating which nonverbal behaviors signify components of theory of mind, and in pointing to possible stepping points in the evolution of what many claim to be a uniquely human aspect of social cognition. While it is difficult to study human-like theory of mind and mental states in species which we do not yet describe as "minded" at all, and about whose potential mental states we have an incomplete understanding, researchers can focus on simpler components of more complex capabilities. For example, many researchers focus on animals' understanding of intention, gaze, perspective, or knowledge (or rather, what another being has seen). Call and Tomasello's study that looked at understanding of intention in orangutans, chimpanzees and children showed that all three species understood the difference between accidental and intentional acts. Part of the difficulty in this line of research is that observed phenomena can often be explained as simple stimulus-response learning, as it is in the nature of any theorizers of mind to have to extrapolate internal mental states from observable behavior. Recently, most non-human theory of mind research has focused on monkeys and great apes, who are of most interest in the study of the evolution of human social cognition. Other studies relevant to attributions theory of mind have been conducted using plover
s and dogs, and have shown preliminary evidence of understanding attention—one precursor of theory of mind—in others.
There has been some controversy over the interpretation of evidence purporting to show theory of mind ability—or inability—in animals. Two examples serve as demonstration: first, Povinelli et al. (1990) presented chimpanzees with the choice of two experimenters from which to request food: one who had seen where food was hidden, and one who, by virtue of one of a variety of mechanisms (having a bucket or bag over his head; a blindfold over his eyes; or being turned away from the baiting) does not know, and can only guess. They found that the animals failed in most cases to differentially request food from the "knower." By contrast, Hare, Call, and Tomasello (2001) found that subordinate chimpanzees were able to use the knowledge state of dominant rival chimpanzees to determine which container of hidden food they approached.
Belief
Belief is the psychological state in which an individual holds a proposition or premise to be true.-Belief, knowledge and epistemology:The terms belief and knowledge are used differently in philosophy....
s, intents
Intention
Intention is an agent's specific purpose in performing an action or series of actions, the end or goal that is aimed at. Outcomes that are unanticipated or unforeseen are known as unintended consequences....
, desires
Desire (emotion)
Desire is a sense of longing for a person or object or hoping for an outcome. Desire is the fire that sets action aflame. The same sense is expressed by emotions such as "craving" or "hankering". When a person desires something or someone, their sense of longing is excited by the enjoyment or the...
, pretending
Role-playing
Role-playing refers to the changing of one's behaviour to assume a role, either unconsciously to fill a social role, or consciously to act out an adopted role...
, knowledge
Knowledge
Knowledge is a familiarity with someone or something unknown, which can include information, facts, descriptions, or skills acquired through experience or education. It can refer to the theoretical or practical understanding of a subject...
, etc.—to oneself and others and to understand that others have beliefs, desires and intentions that are different from one's own. Though there are philosophical
Philosophy
Philosophy is the study of general and fundamental problems, such as those connected with existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing such problems by its critical, generally systematic approach and its reliance on rational...
approaches to issues raised in such discussions, theory of mind
Mind
The concept of mind is understood in many different ways by many different traditions, ranging from panpsychism and animism to traditional and organized religious views, as well as secular and materialist philosophies. Most agree that minds are constituted by conscious experience and intelligent...
as such is distinct from the philosophy of mind
Philosophy of mind
Philosophy of mind is a branch of philosophy that studies the nature of the mind, mental events, mental functions, mental properties, consciousness and their relationship to the physical body, particularly the brain. The mind-body problem, i.e...
.
Defining theory of mind
Theory of mind is a theoryTheory
The English word theory was derived from a technical term in Ancient Greek philosophy. The word theoria, , meant "a looking at, viewing, beholding", and referring to contemplation or speculation, as opposed to action...
insofar as the mind is not directly observable. The presumption that others have a mind is termed a theory of mind because each human can only intuit the existence of his or her own mind through introspection, and no one has direct access to the mind of another. It is typically assumed that others have minds by analogy with one's own, and based on the reciprocal nature of social interaction, as observed in joint attention, the functional use of language, and understanding of others' emotions and actions. Having a theory of mind allows one to attribute thoughts, desires, and intentions to others, to predict or explain their actions, and to posit their intentions. As originally defined, it enables one to understand that mental states can be the cause of—and thus be used to explain and predict—others’ behavior. Being able to attribute mental states to others and understanding them as causes of behavior implies, in part, that one must be able to conceive of the mind as a “generator of representations”. If a person does not have a complete theory of mind it may be a sign of cognitive or developmental impairment.
Theory of mind appears to be an innate potential ability in humans, but one requiring social and other experience over many years to bring to fruition. Different people may develop more, or less, effective theories of mind. Empathy
Empathy
Empathy is the capacity to recognize and, to some extent, share feelings that are being experienced by another sapient or semi-sapient being. Someone may need to have a certain amount of empathy before they are able to feel compassion. The English word was coined in 1909 by E.B...
is a related concept, meaning experientially recognizing and understanding the states of mind, including beliefs, desires and particularly emotions of others, often characterized as the ability to "put oneself into another's shoes." Recent neuro ethological
Ethology
Ethology is the scientific study of animal behavior, and a sub-topic of zoology....
studies of animal behaviour, suggest even rodents may exhibit ethical or empathic abilities. Neo-Piagetian theories of cognitive development
Neo-Piagetian theories of cognitive development
Jean Piaget's theory of cognitive development has been criticized on many grounds. One criticism is concerned with the very nature of development itself. It is suggested that Piaget's theory does not explain why development from stage to stage occurs. The theory is also criticized for ignoring...
maintain that theory of mind is a byproduct of a broader hypercognitive ability of the human mind to register, monitor, and represent its own functioning.
Research on theory of mind in a number of different populations (human and animal, adults and children, normally- and atypically-developing) has grown rapidly in the almost 30 years since Premack
David Premack
David Premack is currently emeritus professor of psychology at the University of Pennsylvania. He was educated at the University of Minnesota when logical positivism was in full bloom. The departments of Psychology and Philosophy were closely allied...
and Woodruff's paper, "Does the chimpanzee have a theory of mind?", as have the theories of theory of mind. The emerging field of social neuroscience
Social neuroscience
Social neuroscience is an interdisciplinary field devoted to understanding how biological systems implement social processes and behavior, and to using biological concepts and methods to inform and refine theories of social processes and behavior. Humans are fundamentally a social species, rather...
has also begun to address this debate, by imaging humans while performing tasks demanding the understanding of an intention, belief or other mental state.
An alternative account of theory of mind (ToM) is given within operant psychology and provides significant empirical evidence for a functional account of both perspective taking and empathy. The most developed operant approach is founded on research on derived relational responding and is subsumed within what is called, "Relational Frame Theory." According to this view empathy and perspective taking comprise a complex set of derived relational abilities based on learning to discriminate and verbally respond to ever more complex relations between self, others, place, and time, and the transformation of function through established relations.
Philosophical roots
Contemporary discussions of ToM have their roots in philosophical debate—most broadly, from the time of Descartes’ "Second Meditation," which set the groundwork for considering the science of the mind. Most prominent recently are two contrasting approaches, in the philosophical literature, to theory of mind: theory-theory and simulation theory. The theory-theorist imagines a veritable theory—"folk psychology"—used to reason about others' minds. The theory is developed automatically and innately, though instantiated through social interactions.On the other hand, simulation theory suggests ToM is not, at its core, theoretical. Two kinds of simulationism have been proposed. One version (Alvin Goldman
Alvin Goldman
Alvin Ira Goldman is an American professor of Philosophy at Rutgers University in New Jersey. He previously taught at the University of Michigan and at the University of Arizona. He earned his PhD from Princeton University and is married to Holly Smith, a well known ethicist, former...
's) emphasizes that one must recognize one's own mental states before ascribing mental states to others by simulation. The second version of simulation theory proposes that each person comes to know his or her own and others' minds through what Robert Gordon names a logical "ascent routine" which answers questions about mental states by re-phrasing the question as a metaphysical one. For example, if Zoe asks Pam, "Do you think that dog wants to play with you?", Pam would ask herself, "Does that dog want to play with me?" to determine her own response. She could equally well ask that to answer the question of what Zoe might think. Both hold that people generally understand one another by simulating being in the other's shoes.
One of the differences between the two theories that have influenced psychological consideration of ToM is that theory-theory describes ToM as a detached theoretical process that is an innate feature, whereas simulation theory portrays ToM as a kind of knowledge that allows one to form predictions of someone's mental states by putting oneself in the other person's shoes and simulating them. These theories continue to inform the definitions of theory of mind at the heart of scientific ToM investigation.
The philosophical roots of the Relational Frame Theory account of ToM arise from contextual psychology and refer to the study of organisms (both human and non-human) interacting in and with a historical and current situational context. It is an approach based on contextualism, a philosophy in which any event is interpreted as an ongoing act inseparable from its current and historical context and in which a radically functional approach to truth and meaning is adopted. As a variant of contextualism, RFT focuses on the construction of practical, scientific knowledge. This scientific form of contextual psychology is virtually synonymous with the philosophy of operant psychology.
Theory of mind development
The study of which animals are capable of attributing knowledge and mentalstates to others, as well as when in human ontogeny
Ontogeny
Ontogeny is the origin and the development of an organism – for example: from the fertilized egg to mature form. It covers in essence, the study of an organism's lifespan...
and phylogeny
Phylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...
this ability
developed, has identified a number of precursory behaviors to a theory of mind.
Understanding attention, understanding of others' intentions, and imitative
experience with other people are hallmarks of a theory of mind which may be
observed early in the development of what will later become a full-fledged
theory. In studies with non-human animals and pre-verbal humans, in particular,
researchers look to these behaviors preferentially in making inferences about
mind.
Baron-Cohen identified the infant's understanding of attention in others, a social skill found by 7 to 9 months of age, as a "critical precursor" to the development of theory of mind. Understanding attention involves understanding that seeing can be directed selectively as attention, that the looker assesses the seen object as "of interest," and that seeing can induce beliefs. Attention can be directed and shared by the act of pointing, a joint attention behavior which requires taking into account another person's mental state, particularly whether the person notices an object or finds it of interest. Baron-Cohen speculates that the inclination to spontaneously reference an object in the world as of interest ("proto-declarative pointing") and to likewise appreciate the directed attention and interests of another may be the underlying motive behind all human communication.
Understanding of others' intentions is another critical precursor to understanding other minds because intentionality, or "aboutness", is a fundamental feature of mental states and events. The "intentional stance" has been defined by Dennett as an understanding that others' actions are goal-directed and arise from particular beliefs or desires. Both 2- and 3-year-old children could discriminate when an experimenter intentionally vs. accidentally marked a box as baited with stickers. Even earlier in ontogeny, Andrew N. Meltzoff
Andrew N. Meltzoff
Andrew N. Meltzoff is an American psychologist and an internationally recognized expert on infant and child development. His discoveries about infant imitation greatly advanced the scientific understanding of early cognition, personality and brain development.-Background:Meltzoff received a B.A....
found that 18 month-old infants could perform target manipulations that adult experimenters attempted and failed, suggesting the infants could represent the object-manipulating behavior of adults as involving goals and intentions. While attribution of intention (the box-marking) and knowledge (false-belief tasks) is investigated in young humans and nonhuman animals to detect precursors to a theory of mind, Gagliardi et al. have pointed out that even adult humans do not always act in a way consistent with an attributional perspective. In the experiment, adult human subjects came to make choices about baited containers when guided by confederates who could not see (and therefore, not know) which container had been baited.
Recent research in developmental psychology suggests that the infant's ability to imitate others lies at the origins of both a theory of mind and other social-cognitive achievements like perspective-taking and empathy. According to Meltzoff, the infant's innate understanding that others are "like me" allows it to recognize the equivalence between the physical and mental states apparent in others and those felt by the self. For example, the infant uses his own experiences orienting his head/eyes toward an object of interest to understand the movements of others who turn toward an object, that is, that they will generally attend to objects of interest or significance. Some researchers in comparative disciplines have hesitated to put a too-ponderous weight on imitation as a critical precursor to advanced human social-cognitive skills like mentalizing and empathizing, especially if true imitation is no longer employed by adults. A test of imitation by Horowitz found that adult subjects imitated an experimenter demonstrating a novel task far less closely than children subjects did. Horowitz points out that the precise psychological state underlying imitation is unclear and cannot, by itself, be used to draw conclusions about the mental states of humans.
Empirical investigation
Whether children younger than 3 or 4 years old may have a theory of mind is a topic of debate among researchers. It is a challenging question, due to the difficulty of assessing what pre-linguistic children understand about others and the world. Tasks used in research into the development of ToM must take into account the umweltUmwelt
According to Jakob von Uexküll and Thomas A. Sebeok, umwelt is the "biological foundations that lie at the very epicenter of the study of both communication and signification in the human [and non-human] animal." The term is usually translated as "self-centered world"...
—(the German word Umwelt means "environment" or "surrounding world")—of the pre-verbal child.
False-belief task
One of the most important milestones in theory of mind development is gaining the ability to attribute false belief: that is, to recognize that others can have beliefs about the world that are diverging. To do this, it is suggested, one must understand how knowledge is formed, that people’s beliefs are based on their knowledge, that mental states can differ from reality, and that people’s behavior can be predicted by their mental states. Numerous versions of the false-belief task have been developed, based on the initial task done by Wimmer and Perner (1983).In the most common version of the false-belief task (often called the ‘Sally-Anne’ task
Sally-Anne test
The Sally–Anne test is a psychological test, used in developmental psychology to measure a person's social cognitive ability to attribute false beliefs to others...
), children are told or shown a story involving two characters. For example, the child is shown two dolls, Sally and Anne, who have a basket and a box, respectively. Sally also has a marble, which she places in her basket, and then leaves to take a walk. While she is out of the room, Anne takes the marble from the basket, eventually putting it in the box. Sally returns, and the child is then asked where Sally will look for the marble. The child passes the task if she answers that Sally will look in the basket, where she put the marble; the child fails the task if she answers that Sally will look in the box, where the child knows the marble is hidden, even though Sally cannot know, since she did not see it hidden there. In order to pass the task, the child must be able to understand that another’s mental representation of the situation is different from their own, and the child must be able to predict behavior based on that understanding. The results of research using false-belief tasks have been fairly consistent: most normally-developing children are unable to pass the tasks until around age four. (Notably, while most children, including those with Down syndrome
Down syndrome
Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...
, are able to pass this test, in one study, 80% of children diagnosed with autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
were unable to do so.)
Appearance-reality task
Other tasks have been developed to try to solve the problems inherent in the false-belief task. In the "appearance-reality", or "Smarties" task, experimenters ask children what they believe to be the contents of a box that looks as though it holds a candy called "Smarties." After the child guesses (usually) "Smarties," each is shown that the box in fact contained pencils. The experimenter then re-closes the box and asks the child what she thinks another person, who has not been shown the true contents of the box, will think is inside. The child passes the task if she responds that another person will think that there are "Smarties" in the box, but fails the task if she responds that another person will think that the box contains pencils. Gopnik & Astington (1988) found that children pass this test at age four or five years.Other tasks
The "false-photograph" task is another task that serves as a measure of theory of mind development. In this task, children must reason about what is represented in a photograph that differs from the current state of affairs. Within the false-photograph task, there is either a location or identity change. In the location-change task, the child is told a story about a character that puts an object in one location (e.g., chocolate in a green cupboard) and takes a Polaroid photograph of the scene. While the photograph is developing, the object is moved to a different location (e.g., to a blue cupboard). The child is then asked two control questions, “When we first took the picture, where was the object? Where is the object now?” The subject is also asked a false-photograph question, “Where is the object in the picture?” The child passes the task if she correctly identifies the location of the object in the picture and the actual location of the object at the time of the question.In order to make tasks more accessible for young children, non-human animals, and autistic individuals, theory of mind research has begun employing non-verbal paradigms. One category of tasks uses a preferential looking paradigm, with looking time as the dependent variable. For instance, Woodward found that 9-month-old infants preferred looking at behaviors performed by a human hand over those made by an inanimate hand-like object. Other paradigms look at rates of imitative behavior, the ability to replicate and complete unfinished goal-directed acts, and observations of rates of pretend play
Theory of mind deficits
The theory of mind (ToM) impairment describes a difficulty someone would have with perspective taking. This is also sometimes referred to as mind-blindnessMind-blindness
Mind-blindness can be described as an inability to develop an awareness of what is in the mind of another human. It is not necessarily caused by an inability to imagine an answer, but is often due to not being able to gather enough information to work out which of the many possible answers is...
. This means that individuals with a ToM impairment would have a hard time seeing things from any other perspective than their own. Individuals who experience a theory of mind deficit have difficulty determining the intentions of others, lack understanding of how their behavior affects others, and have a difficult time with social reciprocity. ToM deficits have been observed in people with autism spectrum
Autism spectrum
The term "autism spectrum" is often used to describe disorders that are currently classified as pervasive developmental disorders. Pervasive developmental disorders include autism, Asperger syndrome, Childhood disintegrative disorder, Rett syndrome and Pervasive Developmental Disorder Not Otherwise...
disorders, schizophrenics, persons under the influence of alcohol and narcotics, sleep-deprived persons, and persons who are experiencing severe emotional or physical pain.
Autism
In 1985 Simon Baron-CohenSimon Baron-Cohen
Simon Baron-Cohen FBA is professor of Developmental Psychopathology in the Departments of Psychiatry and Experimental Psychology at the University of Cambridge in the United Kingdom. He is the Director of the University's Autism Research Centre, and a Fellow of Trinity College...
, Alan M. Leslie
Alan M. Leslie
Alan M. Leslie is a Scottish psychologist and Professor of Psychology and Cognitive science at Rutgers University where he directs the Cognitive Development Laboratory.- Education :...
and Uta Frith
Uta Frith
Uta Frith FRS FBA is a leading developmental psychologist working at the Institute of Cognitive Neuroscience at University College London. She has pioneered much of the current research in autism and dyslexia, and has written several books on these issues. Her book 'Autism: Explaining the Enigma'...
published research which suggested that children with autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
do not employ a theory of mind, and suggested that children with autism have particular difficulties with tasks requiring the child to understand another person's beliefs. These difficulties persist when children are matched for verbal skills (Happe, 1995, Child Development) and have been taken as a key feature of autism.
Many individuals classified as having autism have severe difficulty assigning mental states to others, and they seem to lack theory of mind capabilities. Researchers who study the relationship between autism and theory of mind attempt to explain the connection in a variety of ways. One account assumes that theory of mind plays a role in the attribution of mental states to others and in childhood pretend play. According to Leslie, theory of mind is the capacity to mentally represent thoughts, beliefs, and desires, regardless of whether or not the circumstances involved are real. This might explain why individuals with autism show extreme deficits in both theory of mind and pretend play. However, Hobson proposes a social-affective justification, which suggests that a person with autism deficits in theory of mind result from a distortion in understanding and responding to emotions. He suggests that typically developing human beings, unlike individuals with autism, are born with a set of skills (such as social referencing ability) which will later enable them to comprehend and react to other people’s feelings. Other scholars emphasize that autism involves a specific developmental delay, so that children with the impairment vary in their deficiencies, because they experience difficulty in different stages of growth. Very early setbacks can alter proper advancement of joint-attention behaviors, which may lead to a failure to form a full theory of mind.
It has been speculated that ToM exists on a continuum
Continuum
Continuum may refer to:* Continuum , anything that goes through a gradual transition from one condition, to a different condition, without any abrupt changes-Linguistics:...
as opposed to the traditional view of a concrete presence or absence. While some research has suggested that some autistic populations are unable to attribute mental states to others, recent evidence points to the possibility of coping mechanisms that facilitate a spectrum of mindful behavior.
In typically developing humans
Research on theory of mind in autism led to the view that mentalizing abilities are subserved by dedicated mechanisms that can (in some cases) be impaired while general cognitive function remains largely intact. NeuroimagingNeuroimaging
Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function/pharmacology of the brain...
research has supported this view, demonstrating specific brain regions consistently engaged during theory of mind tasks. Early PET
Positron emission tomography
Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...
research on theory of mind, using verbal and pictorial story comprehension tasks, identified a set of regions including the medial prefrontal cortex
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...
(mPFC), and area around posterior superior temporal sulcus
Superior temporal sulcus
The superior temporal sulcus is the sulcus separating the superior temporal gyrus from the middle temporal gyrus in the temporal lobe of the brain. The superior temporal sulcus is the first sulcus inferior to the lateral fissure....
(pSTS), and sometimes precuneus
Precuneus
The precuneus is a part of the superior parietal lobule hidden in the medial longitudinal fissure between the two cerebral hemispheres. It is sometimes described as the medial area of the superior parietal cortex. It is involved with episodic memory, visuospatial processing, reflections upon self,...
and amygdala
Amygdala
The ' are almond-shaped groups of nuclei located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.-...
/temporopolar cortex
Brodmann area 38
Brodmann area 38, also BA38 or temporopolar area 38 , is part of the temporal cortex in the human brain. BA 38 is at the anterior end of the temporal lobe, known as the temporal pole....
(reviewed in ). Subsequently, research on the neural basis of theory of mind has diversified, with separate lines of research focused on the understanding of beliefs, intentions, and more complex properties of minds such as psychological traits.
Studies from Rebecca Saxe
Rebecca Saxe
Rebecca Saxe is an Associate Professor of Cognitive Neuroscience in the department of Brain and Cognitive Sciences at MIT. Her research is on the neural basis of social cognition, and in particular she is known for proposing the role of the right temporoparietal junction in thinking about...
's lab at MIT, using a false belief versus false photograph task contrast aimed to isolate the mentalizing component of the false belief task, have very consistently found activation in mPFC, precuneus, and temporo-parietal junction (TPJ), right-lateralized. In particular, it has been proposed that the right TPJ (rTPJ) is selectively involved in representing the beliefs of others. However, some debate exists, as some scientists have noted that the same rTPJ region has been consistently activated during spatial reorienting of visual attention; Jean Decety
Jean Decety
Jean Decety is a neuroscientist and an internationally recognized expert on cognitive neuroscience and social neuroscience. His research focuses on the neurobiological mechanisms underpinning social cognition, particularly empathy, sympathy, emotional self-regulation and more generally...
from the University of Chicago and Jason Mitchell from Harvard have thus proposed that the rTPJ subserves a more general function involved in both false belief understanding and attentional reorienting, rather than a mechanism specialized for social cognition. However, it is possible that the observation of overlapping regions for representing beliefs and attentional reorienting may simply be due to adjacent but distinct neuronal populations that code for each. The resolution of typical fMRI studies may not be good enough to show that distinct/adjacent neuronal populations code for each of these processes. In a study following Decety and Mitchell, Saxe and colleagues used higher-resolution fMRI and showed that the peak of activation for attentional reorienting is approximately 6-10mm above the peak for representing beliefs. Further corroborating that differing populations of neurons may code for each process, they found no similarity in the patterning of fMRI response across space.
Functional imaging has also been used to study the detection of mental state information in Heider-Simmel-esque animations of moving geometric shapes, which typical humans automatically perceive as social interactions laden with intention and emotion. Three studies found remarkably similar patterns of activation during the perception of such animations versus a random or deterministic motion control: mPFC, pSTS, fusiform face area
Fusiform face area
The fusiform face area is a part of the human visual system which might be specialized for facial recognition, although there is some evidence that it also processes categorical information about other objects, particularly familiar ones.-Localization:...
(FFA), and amygdala were selectively engaged during the ToM condition. Another study presented subjects with an animation of two dots moving with a parameterized degree of intentionality (quantifying the extent to which the dots chased each other), and found that pSTS activation correlated with this parameter.
A separate body of research has implicated the posterior superior temporal sulcus in the perception of intentionality in human action; this area is also involved in perceiving biological motion, including body, eye, mouth, and point-light display motion (reviewed in ). One study found increased pSTS activation while watching a human lift his hand versus having his hand pushed up by a piston (intentional versus unintentional action). Several studies have found increased pSTS activation when subjects perceive a human action that is incongruent with the action expected from the actor’s context and inferred intention: for instance, a human performing a reach-to-grasp motion on empty space next to an object, versus grasping the object; a human shifting eye gaze toward empty space next to a checkerboard target versus shifting gaze toward the target; an unladen human turning on a light with his knee, versus turning on a light with his knee while carrying a pile of books; and a walking human pausing as he passes behind a bookshelf, versus walking at a constant speed. In these studies, actions in the "congruent" case have a straightforward goal, and are easy to explain in terms of the actor’s intention; the incongruent actions, on the other hand, require further explanation (why would someone twist empty space next to a gear?), and apparently demand more processing in the STS. Note that this region is distinct from the temporo-parietal area activated during false belief tasks. Also note that pSTS activation in most of the above studies was largely right-lateralized, following the general trend in neuroimaging studies of social cognition and perception: also right-lateralized are the TPJ activation during false belief tasks, the STS response to biological motion, and the FFA response to faces.
Neuropsychological
Neuropsychology
Neuropsychology studies the structure and function of the brain related to specific psychological processes and behaviors. The term neuropsychology has been applied to lesion studies in humans and animals. It has also been applied to efforts to record electrical activity from individual cells in...
evidence has provided support for neuroimaging results on the neural basis of theory of mind. A study with patients suffering from a lesion of the temporoparietal junction
Temporoparietal junction
The temporoparietal junction is an area of the brain where the temporal and parietal lobes meet, at the posterior end of the Sylvian fissure...
of the brain (between the temporal lobe
Temporal lobe
The temporal lobe is a region of the cerebral cortex that is located beneath the Sylvian fissure on both cerebral hemispheres of the mammalian brain....
and parietal lobe
Parietal lobe
The parietal lobe is a part of the Brain positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different modalities, particularly determining spatial sense and navigation. For example, it comprises somatosensory cortex and the...
) reported that they have difficulty with some theory of mind tasks. This shows that theory of mind abilities are associated with specific parts of the human brain. However, the fact that the medial prefrontal cortex and temporoparietal junction are necessary for theory of mind tasks does not imply that these regions are specific to that function. TPJ and mPFC may subserve more general functions necessary for ToM.
Research by Vittorio Gallese
Vittorio Gallese
Vittorio Gallese is professor of human physiology at the University of Parma, Italy with appointments in the departments of neuroscience, psychiatry and psychology. He is an expert in neurophysiology, neuroscience, social neuroscience, and philosophy of mind. Gallese is one of the discoverers of...
, Luciano Fadiga and Giacomo Rizzolatti
Giacomo Rizzolatti
Giacomo Rizzolatti is an Italian Neurophysiologist who works at the University of Parma. He is the Senior Scientist of the research team that discovered mirror neurons in the frontal and parietal cortex of the macaque monkey, and has written many scientific articles on the topic. He is a past...
(reviewed in ) has shown that some sensorimotor neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
s, which are referred to as mirror neuron
Mirror neuron
A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour of the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other...
s, first discovered in the premotor cortex
Premotor cortex
The premotor cortex is an area of motor cortex lying within the frontal lobe of the brain. It extends 3 mm anterior to the primary motor cortex, near the Sylvian fissure, before narrowing to approximately 1 mm near the medial longitudinal fissure, which serves as the posterior border for...
of rhesus monkeys, may be involved in action understanding. Single-electrode recording revealed that these neurons fired when a monkey performed an action and when the monkey viewed another agent carrying out the same task. Similarly, fMRI studies with human participants have shown brain regions (assumed to contain mirror neurons) are active when one person sees another person's goal-directed action. These data have led some authors to suggest that mirror neurons may provide the basis for theory of mind in the brain, and to support simulation theory of mind reading (see above).
However, there is also evidence against the link between mirror neurons and theory of mind. First, macaque monkeys
Macaque
The macaques constitute a genus of Old World monkeys of the subfamily Cercopithecinae. - Description :Aside from humans , the macaques are the most widespread primate genus, ranging from Japan to Afghanistan and, in the case of the barbary macaque, to North Africa...
have mirror neurons but do not seem to have a 'human-like' capacity to understand theory of mind and belief. Second, fMRI studies of theory of mind typically report activation in the mPFC, temporal poles and TPJ or STS, but these brain areas are not part of the mirror neuron system. Some investigators, like developmental psychologist Andrew Meltzoff and neuroscientist Jean Decety
Jean Decety
Jean Decety is a neuroscientist and an internationally recognized expert on cognitive neuroscience and social neuroscience. His research focuses on the neurobiological mechanisms underpinning social cognition, particularly empathy, sympathy, emotional self-regulation and more generally...
, believe that mirror neurons merely facilitate learning through imitation and may provide a precursor to the development of ToM. Others, like philosopher Shaun Gallagher
Shaun Gallagher
Shaun Gallagher is an American philosopher. He holds the Lillian and Morrie Moss Chair of Excellence in Philosophy at the University of Memphis...
, suggest that mirror-neuron activation, on a number of counts, fails to meet the definition of simulation as proposed by the simulation theory of mindreading.
In autism
Several neuroimaging studies have looked at the neural basis theory of mind impairment in subjects with Asperger syndromeAsperger syndrome
Asperger's syndrome that is characterized by significant difficulties in social interaction, alongside restricted and repetitive patterns of behavior and interests. It differs from other autism spectrum disorders by its relative preservation of linguistic and cognitive development...
and high-functioning autism
High-functioning autism
High-functioning autism is an informal term applied to autistic people who are deemed to be "higher functioning" than other autistic people, by one or more metrics. There is no consensus as to the definition. HFA is not yet a recognised diagnosis in the DSM-IV-TR or the ICD-10.The amount of...
(HFA). The first PET study of theory of mind in autism (also the first neuroimaging study using a task-induced activation paradigm in autism) employed a story comprehension task, replicating a prior study in normal individuals. This study found displaced and diminished mPFC activation in subjects with autism. However, because the study used only six subjects with autism, and because the spatial resolution of PET imaging is relatively poor, these results should be considered preliminary.
A subsequent fMRI study scanned normally developing adults and adults with HFA while performing a "reading the mind in the eyes" task—viewing a photo of a human’s eyes and choosing which of two adjectives better describes the person’s mental state, versus a gender discrimination control. The authors found activity in orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...
, STS, and amygdala in normal subjects, and found no amygdala activation and abnormal STS activation in subjects with autism.
A more recent PET study looked at brain activity in individuals with HFA and Asperger syndrome while viewing Heider-Simmel animations (see above) versus a random motion control. In contrast to normally developing subjects, those with autism showed no STS or FFA activation, and significantly less mPFC and amygdala activation. Activity in extrastriate regions
Extrastriate cortex
The extrastriate cortex is the region of the occipital cortex of the mammalian brain located next to the primary visual cortex, which is also named striate cortex because of its appeareance in the microscope. The extrastriate cortex encompasses multiple functional areas, including V3, V4, V5/MT...
V3 and LO was identical across the two groups, suggesting intact lower-level visual processing in the subjects with autism. The study also reported significantly less functional connectivity between STS and V3 in the autism group. Note, however, that decreased temporal correlation between activity in STS and V3 would be expected simply from the lack of an evoked response in STS to intent-laden animations in subjects with autism; a more informative analysis would be to compute functional connectivity after regressing out evoked responses from all time series.
A subsequent study, using the incongruent/congruent gaze shift paradigm described above, found that in high-functioning adults with autism, posterior STS (pSTS) activation was undifferentiated while watching a human shift gaze toward a target and toward adjacent empty space. The lack of additional STS processing in the incongruent state may suggest that these subjects fail to form an expectation of what the actor should do given contextual information, or that information about the violation of this expectation doesn’t reach STS; both explanations involve an impairment in the ability to link eye gaze shifts with intentional explanations. This study also found a significant anticorrelation between STS activation in the incongruent-congruent contrast and social subscale score on the Autism Diagnostic Interview-Revised
Autism Diagnostic Interview-Revised
The Autism Diagnostic Interview-Revised is structured interview conducted with the parents of individuals who have been referred for the evaluation of possible autism or autism spectrum disorders...
, but not scores on the other subscales.
In 2011, an fMRI study demonstrated that right temporoparietal junction
Temporoparietal junction
The temporoparietal junction is an area of the brain where the temporal and parietal lobes meet, at the posterior end of the Sylvian fissure...
(rTPJ) of higher-functioning adults with autism was not selectively activated more for mentalizing judgments when compared to physical judgments about self and other. rTPJ selectivity for mentalizing was also related to individual variation on clinical measures of social impairment; individuals whose rTPJ was increasingly more active for mentalizing compared to physical judgments were less socially impaired, while those who showed little to no difference in response to mentalizing or physical judgments were the most socially impaired. This evidence builds on work in typical development that suggests rTPJ is critical for representing mental state information, irrespective of whether it is about oneself or others. It also points to an explanation at the neural level for the pervasive mind-blindness
Mind-blindness
Mind-blindness can be described as an inability to develop an awareness of what is in the mind of another human. It is not necessarily caused by an inability to imagine an answer, but is often due to not being able to gather enough information to work out which of the many possible answers is...
difficulties in autism that are evident throughout the lifespan.
Non-human theory of mind
As the title of Premack and Woodruff's 1978 article "Does the chimpanzee have a theory of mind?" indicates, it is also important to ask if other animals besides humans have a geneticGenetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
endowment and social
Social psychology
Social psychology is the scientific study of how people's thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others. By this definition, scientific refers to the empirical method of investigation. The terms thoughts, feelings, and behaviors include all...
environment that allows them to acquire a theory of mind in the same way that human children do. This is a contentious issue because of the problem of inferring from animal behavior the existence of thinking
Thought
"Thought" generally refers to any mental or intellectual activity involving an individual's subjective consciousness. It can refer either to the act of thinking or the resulting ideas or arrangements of ideas. Similar concepts include cognition, sentience, consciousness, and imagination...
, of the existence of a concept of self
Self (psychology)
The psychology of self is the study of either the cognitive and affective representation of one's identity or the subject of experience. The earliest formulation of the self in modern psychology derived from the distinction between the self as I, the subjective knower, and the self as Me, the...
or self-awareness
Self-awareness
Self-awareness is the capacity for introspection and the ability to reconcile oneself as an individual separate from the environment and other individuals...
, or of particular thoughts. One difficulty with non-human studies of ToM is the lack of sufficient numbers of naturalistic observation, giving insight into what the evolutionary pressures might be on a species' development of theory of mind.
Non-human research still has a major place in this field, however, and is especially useful in illuminating which nonverbal behaviors signify components of theory of mind, and in pointing to possible stepping points in the evolution of what many claim to be a uniquely human aspect of social cognition. While it is difficult to study human-like theory of mind and mental states in species which we do not yet describe as "minded" at all, and about whose potential mental states we have an incomplete understanding, researchers can focus on simpler components of more complex capabilities. For example, many researchers focus on animals' understanding of intention, gaze, perspective, or knowledge (or rather, what another being has seen). Call and Tomasello's study that looked at understanding of intention in orangutans, chimpanzees and children showed that all three species understood the difference between accidental and intentional acts. Part of the difficulty in this line of research is that observed phenomena can often be explained as simple stimulus-response learning, as it is in the nature of any theorizers of mind to have to extrapolate internal mental states from observable behavior. Recently, most non-human theory of mind research has focused on monkeys and great apes, who are of most interest in the study of the evolution of human social cognition. Other studies relevant to attributions theory of mind have been conducted using plover
Plover
Plovers are a widely distributed group of wading birds belonging to the subfamily Charadriinae. There are about 40 species in the subfamily, most of them called "plover" or "dotterel". The closely related lapwing subfamily, Vanellinae, comprises another 20-odd species.Plovers are found throughout...
s and dogs, and have shown preliminary evidence of understanding attention—one precursor of theory of mind—in others.
There has been some controversy over the interpretation of evidence purporting to show theory of mind ability—or inability—in animals. Two examples serve as demonstration: first, Povinelli et al. (1990) presented chimpanzees with the choice of two experimenters from which to request food: one who had seen where food was hidden, and one who, by virtue of one of a variety of mechanisms (having a bucket or bag over his head; a blindfold over his eyes; or being turned away from the baiting) does not know, and can only guess. They found that the animals failed in most cases to differentially request food from the "knower." By contrast, Hare, Call, and Tomasello (2001) found that subordinate chimpanzees were able to use the knowledge state of dominant rival chimpanzees to determine which container of hidden food they approached.
See also
- AutismAutismAutism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
- Cephalopod intelligenceCephalopod intelligenceCephalopod intelligence has an important comparative aspect in the understanding of intelligence because it relies on a nervous system fundamentally different from that of vertebrates...
- Cetacean intelligenceCetacean intelligenceCetacean intelligence denotes the cognitive capabilities of the Cetacea order of mammals, which includes whales, porpoises, and dolphins.-Brain size:...
- ConsciousnessConsciousnessConsciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...
- EmpathyEmpathyEmpathy is the capacity to recognize and, to some extent, share feelings that are being experienced by another sapient or semi-sapient being. Someone may need to have a certain amount of empathy before they are able to feel compassion. The English word was coined in 1909 by E.B...
- Identity theory of mind
- Mental bodyMental bodyThe mental body is one of the subtle bodies in esoteric philosophies, in some religious teachings and in New Age thought. It is understood as a sort of body made up of thoughts, just as the emotional body consists of emotions and the physical body is made up of matter...
- MentalizationMentalizationMentalization is a psychological concept that describes the ability to understand the mental state of oneself and others which underlies overt behaviour. Mentalization can be seen as a form of imaginative mental activity, which allow us to perceive and interpret human behaviour in terms of...
- MindMindThe concept of mind is understood in many different ways by many different traditions, ranging from panpsychism and animism to traditional and organized religious views, as well as secular and materialist philosophies. Most agree that minds are constituted by conscious experience and intelligent...
- The Mind of an ApeThe Mind of an ApeThe Mind of an Ape is a 1983 book by David and Ann James Premack. In it, the authors argue that it is possible to teach language to great apes...
- Mind-body problem
- Mirror neurons
- Philosophy of mindPhilosophy of mindPhilosophy of mind is a branch of philosophy that studies the nature of the mind, mental events, mental functions, mental properties, consciousness and their relationship to the physical body, particularly the brain. The mind-body problem, i.e...
- Problem of other mindsProblem of other mindsThe problem of other minds has traditionally been regarded as an epistemological challenge raised by the skeptic. The challenge may be expressed as follows: given that I can only observe the behavior of others, how can I know that others have minds? The thought behind the question is that no matter...
- Quantum mindQuantum mindThe quantum mind or quantum consciousness hypothesis proposes that classical mechanics cannot explain consciousness, while quantum mechanical phenomena, such as quantum entanglement and superposition, may play an important part in the brain's function, and could form the basis of an explanation of...
- Social neuroscienceSocial neuroscienceSocial neuroscience is an interdisciplinary field devoted to understanding how biological systems implement social processes and behavior, and to using biological concepts and methods to inform and refine theories of social processes and behavior. Humans are fundamentally a social species, rather...
- Turing testTuring testThe Turing test is a test of a machine's ability to exhibit intelligent behaviour. In Turing's original illustrative example, a human judge engages in a natural language conversation with a human and a machine designed to generate performance indistinguishable from that of a human being. All...