Time perception
Encyclopedia
Time perception is a field of study within psychology
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...

 and neuroscience
Neuroscience
Neuroscience is the scientific study of the nervous system. Traditionally, neuroscience has been seen as a branch of biology. However, it is currently an interdisciplinary science that collaborates with other fields such as chemistry, computer science, engineering, linguistics, mathematics,...

. It refers to the sense of time, which differs from other senses since time cannot be directly perceived but must be reconstructed by the brain. Humans can perceive relatively short periods of time, in the order of milliseconds, and also durations that are a significant fraction of a lifetime. Human perception of duration is subjective and variable. Some researchers attempt to categorise people by how they differ in their perception of time (see Personality characteristics).

Pioneering work, emphasizing species-specific differences, was done by Karl Ernst von Baer
Karl Ernst von Baer
Karl Ernst Ritter von Baer, Edler von Huthorn also known in Russia as Karl Maksimovich Baer was an Estonian naturalist, biologist, geologist, meteorologist, geographer, a founding father of embryology, explorer of European Russia and Scandinavia, a member of the Russian Academy of Sciences, a...

. Experimental work began under the influence of the psycho-physical notions of Gustav Theodor Fechner with studies of the relationship between perceived and measured time. Work with animals conducted by Jakob von Uexküll
Jakob von Uexküll
Jakob Johann von Uexküll was a Estonian biologist who worked in the fields of muscular physiology, animal behaviour studies, and the cybernetics of life. However, his most notable contribution is the notion of umwelt, used by semiotician Thomas Sebeok...

 included measurement of length of momentum in snails.

Theories

William J. Friedman also contrasted two theories for a sense of time:
  • The strength model of time memory. This posits a memory trace that persists over time, by which one might judge the age of a memory (and therefore how long ago the event remembered occurred) from the strength of the trace. This conflicts with the fact that memories of recent events may fade more quickly than more distant memories.
  • The inference model suggests the time of an event is inferred from information about relations between the event in question and other events whose date or time is known.

Short-term

Although the sense of time is not associated with a specific sensory system the work of psychologist
Psychologist
Psychologist is a professional or academic title used by individuals who are either:* Clinical professionals who work with patients in a variety of therapeutic contexts .* Scientists conducting psychological research or teaching psychology in a college...

s and neuroscientist
Neuroscientist
A neuroscientist is an individual who studies the scientific field of neuroscience or any of its related sub-fields...

s indicates that human brains do have a system governing the perception
Perception
Perception is the process of attaining awareness or understanding of the environment by organizing and interpreting sensory information. All perception involves signals in the nervous system, which in turn result from physical stimulation of the sense organs...

 of time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

, composed of a highly distributed system involving the cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...

, cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...

 and basal ganglia
Basal ganglia
The basal ganglia are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus and other brain areas...

. One particular component, the suprachiasmatic nucleus
Suprachiasmatic nucleus
The suprachiasmatic nucleus or nuclei, abbreviated SCN, is a tiny region on the brain's midline, situated directly above the optic chiasm. It is responsible for controlling circadian rhythms...

, is responsible for the circadian (or daily) rhythm
Circadian rhythm
A circadian rhythm, popularly referred to as body clock, is an endogenously driven , roughly 24-hour cycle in biochemical, physiological, or behavioural processes. Circadian rhythms have been widely observed in plants, animals, fungi and cyanobacteria...

, while other cell clusters appear to be capable of shorter-range (ultradian
Ultradian
Ultradian rhythms are recurrent periods or cycles repeated throughout a 24-hour circadian day. In contrast, infradian rhythms, such as the human menstrual cycle, have periods longer than a day....

) timekeeping.

Experiments have shown that rats can successfully estimate intervals of time around 40 seconds despite having their cortex
Cortex
Cortex may refer to:-Sciences:* Cortex , the outer portion of the stem or root of a plant...

entirely removed, which suggests it is a low level (subcortical) process.

Specious present

The specious present is the time duration wherein a state of consciousness
Consciousness
Consciousness 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...

 is experienced as being in the present
Present
Present is a time that is neither past nor future.Present may also refer to:- Time and timing :* Present tense, the grammatical tense of a verb* Before Present, radiocarbon dates relative to AD 1950* Presenting, a medical term* Presenteeism...

. The term was first introduced by the philosopher E. R. Clay. and developed by William James
William James
William James was a pioneering American psychologist and philosopher who was trained as a physician. He wrote influential books on the young science of psychology, educational psychology, psychology of religious experience and mysticism, and on the philosophy of pragmatism...

. A version of the concept was used by Edmund Husserl
Edmund Husserl
Edmund Gustav Albrecht Husserl was a philosopher and mathematician and the founder of the 20th century philosophical school of phenomenology. He broke with the positivist orientation of the science and philosophy of his day, yet he elaborated critiques of historicism and of psychologism in logic...

 in his works and discussed further by Francisco Varela
Francisco Varela
Francisco Javier Varela García , was a Chilean biologist, philosopher and neuroscientist who, together with his teacher Humberto Maturana, is best known for introducing the concept of autopoiesis to biology.-Biography:...

 based on the writings of Husserl, Heidegger, and Merleau-Ponty. The experienced present is an interval; it's not a momentary instant except 'speciously'.

The concept was further developed by William James
William James
William James was a pioneering American psychologist and philosopher who was trained as a physician. He wrote influential books on the young science of psychology, educational psychology, psychology of religious experience and mysticism, and on the philosophy of pragmatism...

. James defined the specious present to be "the prototype of all conceived times... the short duration of which we are immediately and incessantly sensible". C. D. Broad in "Scientific Thought" (1930) further elaborated on the concept of the specious present, and considered that the Specious Present may be considered as the temporal equivalent of a sensory datum.

Long-term

Psychologists assert that time seems to go faster with age, but the literature on this age-related perception of time remains controversial. One day to an eleven-year-old would be approximately 1/4,000 of their life, while one day to a 55-year-old would be approximately 1/20,000 of their life. This is perhaps why a day would appear much longer to a young child than to an adult. In an experiment comparing a group of subjects aged between 19 and 24 and a group between 60 and 80 asked to estimate when they thought 3 minutes had passed, it was found that the younger group's estimate was on average 3 minutes and 3 seconds, while the older group averaged 3 minutes and 40 seconds, indicating a change in the perception of time with age. People tend to recall recent events as occurring further back in time (backward telescoping) and distant events occurring more recently (forward telescoping).

It has been proposed that the subjective experience of time changes with age due to changes in the individual's biological makeup.

Illusions of time

A temporal illusion is a distortion in sensory perception caused when the time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

 between the occurrence of two or more events is very short (typically less than a second). In such cases a person may misperceive the temporal order of the events. The kappa effect
Kappa effect
-Introduction:The Kappa Effect is a psychological phenomenon related to the perception of distance, time and speed. It is a temporal illusion that, in some cases, can alter one’s judgement of time. The Kappa effect arises when observers judge the amount of elapsed time between two stimuli in a...

 is a form of temporal illusion verifiable by experiment whereby time intervals between visual events are perceived as relatively longer or shorter depending on the relative spatial positions of the events. In other words: the perception of temporal intervals appears to be directly affected, in these cases, by the perception of spatial intervals. The Kappa effect
Kappa effect
-Introduction:The Kappa Effect is a psychological phenomenon related to the perception of distance, time and speed. It is a temporal illusion that, in some cases, can alter one’s judgement of time. The Kappa effect arises when observers judge the amount of elapsed time between two stimuli in a...

 can be displayed when considering a journey made in two parts that take an equal amount of time. Between these two parts, the journey that covers more distance will appear to take longer than the journey covering less distance, even though they take an equal amount of time.

Psychoactive substances

Psychoactive drugs can alter the judgement of time. Some – such as entheogen
Entheogen
An entheogen , in the strict sense, is a psychoactive substance used in a religious, shamanic, or spiritual context. Historically, entheogens were mostly derived from plant sources and have been used in a variety of traditional religious contexts...

s – may also dramatically alter a person's temporal judgement. Substances such as LSD
LSD
Lysergic acid diethylamide, abbreviated LSD or LSD-25, also known as lysergide and colloquially as acid, is a semisynthetic psychedelic drug of the ergoline family, well known for its psychological effects which can include altered thinking processes, closed and open eye visuals, synaesthesia, an...

, psilocybin
Psilocybin
Psilocybin is a naturally occurring psychedelic prodrug, with mind-altering effects similar to those of LSD and mescaline, after it is converted to psilocin. The effects can include altered thinking processes, perceptual distortions, an altered sense of time, and spiritual experiences, as well as...

, and mescaline
Mescaline
Mescaline or 3,4,5-trimethoxyphenethylamine is a naturally occurring psychedelic alkaloid of the phenethylamine class used mainly as an entheogen....

 may affect our time perception. At higher doses time may appear to slow down, stop, speed up, go backwards or even seem out of sequence. In 1955, British MP Christopher Mayhew
Christopher Mayhew
Christopher Paget Mayhew, Baron Mayhew was a British politician who was a Labour Member of Parliament from 1945 to 1950 and from 1951 to 1974, when he left the Labour Party to become a Liberal...

 took mescaline hydrochloride
Mescaline
Mescaline or 3,4,5-trimethoxyphenethylamine is a naturally occurring psychedelic alkaloid of the phenethylamine class used mainly as an entheogen....

 in an experiment under the guidance of his friend, Dr Humphry Osmond
Humphry Osmond
Humphry Fortescue Osmond was a British psychiatrist known for inventing the word psychedelic and for using psychedelic drugs in medical research...

. On the BBC documentary The Beyond Within, he described that half a dozen times during the experiment, he had "a period of time that didn't end for me".

Stimulants can lead both humans and rats to overestimate time intervals, while depressants can have the opposite effect. The level of activity in the brain of neurotransmitters such as dopamine
Dopamine
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...

 and norepinephrine
Norepinephrine
Norepinephrine is the US name for noradrenaline , a catecholamine with multiple roles including as a hormone and a neurotransmitter...

 may be the reason for this.

Clinical disorders

The sense of time is altered in some people with neurological diseases such as Parkinson's disease
Parkinson's disease
Parkinson's disease is a degenerative disorder of the central nervous system...

 and attention deficit disorder.

Along with other perceptual abnormalities, it has been noted by psychologists that schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...

 patients also have an altered sense of time. This was first described in psychology by Minkowski in 1927. Many schizophrenic patients stop perceiving time as a flow of causally linked events, but perceive events as discrete. It has also been suggested that there is a delay in time perception in schizophrenic patients compared to a normal subject.

These possible defects in time perception may play a part in hallucinations and delusions according to some studies. According to an article titled, Altered Subjective Time of Events in Schizophrenia, in the Journal of Nervous and Mental Disease in 2005 (Volume 193(5), May 2005), researchers suggest that "a possible explanation is that abnormal timing judgment leads to a deficit in action attribution and action perception."

Personality characteristics

Some researchers aim to explain the differences between people in the way they relate to the time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

 they have to perform different tasks. They claim that time perception is influenced by both internal-personal
Personality psychology
Personality psychology is a branch of psychology that studies personality and individual differences. Its areas of focus include:* Constructing a coherent picture of the individual and his or her major psychological processes...

 characteristics and by external-environmental
Social environment
The social environment of an individual, also called social context or milieu, is the culture that s/he was educated or lives in, and the people and institutions with whom the person interacts....

 factors. Some theorists suggest that time perception is categorized by two axes: "time perspective" and "time urgency" and these ideas have been used in occupational psychology settings. These axes typically create four personalities that differ in their personal characteristics and the way they deal with tasks.

Time perspective can be affected by genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

, culture
Culture
Culture is a term that has many different inter-related meanings. For example, in 1952, Alfred Kroeber and Clyde Kluckhohn compiled a list of 164 definitions of "culture" in Culture: A Critical Review of Concepts and Definitions...

, religion
Religion
Religion is a collection of cultural systems, belief systems, and worldviews that establishes symbols that relate humanity to spirituality and, sometimes, to moral values. Many religions have narratives, symbols, traditions and sacred histories that are intended to give meaning to life or to...

, arise from education
Education
Education in its broadest, general sense is the means through which the aims and habits of a group of people lives on from one generation to the next. Generally, it occurs through any experience that has a formative effect on the way one thinks, feels, or acts...

, family
Family
In human context, a family is a group of people affiliated by consanguinity, affinity, or co-residence. In most societies it is the principal institution for the socialization of children...

, past employment
Employment
Employment is a contract between two parties, one being the employer and the other being the employee. An employee may be defined as:- Employee :...

, and so on. As it is well known, the timeline axis moves between past, present and future, which is also the way the time perspective axis is organised. People with a present perspective of time have a tendency to believe that the actions in the present do not significantly affect the future. That is, these people do not think that an action taken place in the present will increase the probability of a future outcome. People with this perspective tend to use the term "why do today what can be done tomorrow?" Individuals with personality characteristics of present time perspective tend to think that it is unnecessary to make future plans. These individuals also tend to take risks and act impulsively. People with future perspective tend to believe that an action taken place in the present increases the probability of a future outcome. These people are very goal-oriented, with high capacity to infer future results, usually prepare task lists, use a calendar, and tend to wear a watch. When a team is assembled from the majority of future time perspective people, the team tends to be more "flexible" and tends to make more changes in strategic thinking than teams with more present time perception individuals. Such an individual will delay his or her performances to the very last moment, which can at times lead to inability to meet deadlines. When such a person belongs to a work team, he/she makes the team less focused strategically, being late in submitting tasks and acting impulsively.

Time urgency relates to the need for quick response or action, to achieve a particular goal (or non existence of this feeling). It can be described as an axis ranging from high to low.

The two dimensions described above, produce four types of personalities, that can be described as follows:

Organizers have high time urgency and future time perspective and are characterized by high awareness of time, scheduling tasks and activities and high achievement striving.

Crammers have high time urgency and present time perspective and are characterized by high awareness of time, needing to exert control over deadlines, competitiveness, high achievement striving and impatience.

Relators have low time urgency and present time perspective and are characterized by attending little to deadlines or passage of time, taking risks, acting impulsively, focusing on present tasks and focusing on relations with others.

Visioners have low time urgency and future time perspective and are characterized by attending little to deadlines or passage of time, taking risks, acting impulsively and focusing on future goals.

Sources and further reading


External links

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