LIDA (cognitive architecture)
Encyclopedia
The LIDA cognitive architecture
Cognitive architecture
A cognitive architecture is a blueprint for intelligent agents. It proposes computational processes that act like certain cognitive systems, most often, like a person, or acts intelligent under some definition. Cognitive architectures form a subset of general agent architectures...

 is an integrated artificial cognitive system that attempts to model a broad spectrum of cognition
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...

 in biological systems, from low-level perception/action to high-level reasoning. Developed primarily by Stan Franklin
Stan Franklin
Stan Franklin is an American scientist and W. Harry Feinstone Interdisciplinary Research Professor at the and co-director of the Institute of Intelligent Systems. He is the author of Artificial Minds and mental father of IDA and its successor LIDA, both computational implementations of...

 and colleagues at the University of Memphis, the LIDA architecture is empirically grounded in cognitive science
Cognitive science
Cognitive science is the interdisciplinary scientific study of mind and its processes. It examines what cognition is, what it does and how it works. It includes research on how information is processed , represented, and transformed in behaviour, nervous system or machine...

 and cognitive neuroscience
Cognitive neuroscience
Cognitive neuroscience is an academic field concerned with the scientific study of biological substrates underlying cognition, with a specific focus on the neural substrates of mental processes. It addresses the questions of how psychological/cognitive functions are produced by the brain...

. In addition to providing hypotheses to guide further research, the architecture can support control structures for software agents and robots. Providing plausible explanations for many cognitive processes, the LIDA conceptual model is also intended as a tool with which to think about how minds work.

Two hypotheses underlie the LIDA architecture and its corresponding conceptual model: 1) Much of human cognition functions by means of frequently iterated (~10 Hz) interactions, called cognitive cycles, between conscious contents, the various memory systems and action selection. 2) These cognitive cycles, serve as the “atoms” of cognition of which higher-level cognitive processes are composed.

Overview

Though it is neither symbolic nor strictly connectionist
Connectionism
Connectionism is a set of approaches in the fields of artificial intelligence, cognitive psychology, cognitive science, neuroscience and philosophy of mind, that models mental or behavioral phenomena as the emergent processes of interconnected networks of simple units...

, LIDA is a hybrid architecture in that it employs a variety of computational mechanisms, chosen for their psychological plausibility. The LIDA cognitive cycle is composed of modules and processes employing these mechanisms.

Computational mechanisms

The LIDA architecture employs several modules that are designed using computational mechanisms drawn from the “new AI.” These include variants of the Copycat Architecture
Copycat (software)
Copycat is a model of analogy making and human cognition based on the concept of the parallel terraced scan, developed in 1988 by Douglas Hofstadter, Melanie Mitchell, and others at the at , Indiana University Bloomington...

, Sparse Distributed Memory, the Schema Mechanism, the Behavior Net, and the Subsumption Architecture
Subsumption architecture
Subsumption architecture is a reactive robot architecture heavily associated with behavior-based robotics. The term was introduced by Rodney Brooks and colleagues in 1986...

.

Psychological and neurobiological underpinnings

As a comprehensive, conceptual and computational cognitive architecture the LIDA architecture is intended to model a large portion of human cognition. Comprising a broad array of cognitive modules and processes, the LIDA architecture attempts to implement and flesh out a number of psychological and neuropsychological theories including Global Workspace Theory
Global Workspace Theory
Global Workspace Theory is a simple Cognitive architecture that has been developed to account qualitatively for a large set of matched pairs of conscious and unconscious processes. It was proposed by Bernard Baars...

, Situated Cognition
Situated cognition
Situated cognition poses that knowing is inseparable from doing by arguing that all knowledge is situated in activity bound to social, cultural and physical contexts....

, perceptual symbol systems, Working Memory
Working memory
Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...

, memory by affordances, long-term working memory, and the H-CogAff architecture.

LIDA’s cognitive cycle

The LIDA cognitive cycle can be subdivided into three phases, the understanding phase, the attention (consciousness) phase, and the action selection and learning phase. Beginning the understanding phase, incoming stimuli activate low-level feature detectors in Sensory Memory. The output engages Perceptual Associative Memory where higher-level feature detectors feed in to more abstract entities such as objects, categories, actions, events, etc. The resulting percept moves to the Workspace where it cues both Transient Episodic Memory and Declarative Memory producing local associations. These local associations are combined with the percept to generate a current situational model; the agent’s understanding of what is going on right now. The attention phase begins with the forming of coalitions of the most salient portions of the current situational model, which then compete for attention, that is a place in the current conscious contents. These conscious contents are then broadcast globally, initiating the learning and action selection phase. New entities and associations, and the reinforcement of old ones, occur as the conscious broadcast reaches the various forms of memory, perceptual, episodic and procedural. In parallel with all this learning, and using the conscious contents, possible action schemes are instantiated from Procedural Memory and sent to Action Selection, where they compete to be the behavior selected for this cognitive cycle. The selected behavior triggers Sensory-Motor Memory to produce a suitable algorithm for its execution, which completes the cognitive cycle.

History

Virtual Mattie (V-Mattie) is a software agent
Software agent
In computer science, a software agent is a piece of software that acts for a user or other program in a relationship of agency, which derives from the Latin agere : an agreement to act on one's behalf...

  that gathers information from seminar organizers, composes announcements of next week's seminars, and mails them each week to a list that it keeps updated, all without the supervision of a human. V-Mattie employed many of the computational mechanisms mentioned above.

Baars
Bernard Baars
Bernard J. Baars is a former Senior Fellow in Theoretical Neurobiology at The Neurosciences Institute in La Jolla, CA., and is currently an Affiliated Fellow there. He is best known as the originator of the global workspace theory, a theory of human cognitive architecture and consciousness...

Global Workspace Theory
Global Workspace Theory
Global Workspace Theory is a simple Cognitive architecture that has been developed to account qualitatively for a large set of matched pairs of conscious and unconscious processes. It was proposed by Bernard Baars...

 (GWT) inspired the transformation of V-Mattie into Conscious Mattie, a software agent with the same domain and tasks whose architecture included a consciousness mechanism à la GWT. Conscious Mattie was the first functionally, though not phenomenally, conscious software agent. Conscious Mattie gave rise to IDA.

IDA (Intelligent Distribution Agent) was developed for the US Navy to fulfill tasks performed by human resource personnel called detailers. At the end of each sailor's tour of duty, he or she is assigned to a new billet. This assignment process is called distribution. The Navy employs almost 300 full time detailers to effect these new assignments. IDA's task is to facilitate this process, by automating the role of detailer. IDA was tested by former detailers and accepted by the Navy. Various Navy agencies supported the IDA project to the tune of some $1,500,000.

The LIDA (Learning IDA) architecture was spawned from IDA by the addition of several styles and modes of learning, as well as much else.

External links

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