4CAPS (Cortical Capacity-Constrained Concurrent Activation-based Production System) is a
cognitive architecture A cognitive architecture refers to both a theory about the structure of the human mind and to a computational instantiation of such a theory used in the fields of artificial intelligence (AI) and computational cognitive science. The formalized mod ...
developed by
Marcel A. Just and Sashank Varma at
Carnegie Mellon University
Carnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania. One of its predecessors was established in 1900 by Andrew Carnegie as the Carnegie Technical Schools; it became the Carnegie Institute of Technology ...
.
[Just, M. A., & Varma, S. (2007). The organization of thinking: What functional brain imaging reveals about the neuroarchitecture of complex cognition. ''Cognitive, Affective, & Behavioral Neuroscience'', ''7(3)'', 153-191.] It is the successor of the CAPS and 3CAPS cognitive architectures.
Overview and Assumptions
In 4CAPS computations are distributed and dynamically balanced among independent processing centers. Like in other cognitive architectures (e.g.,
ACT-R
ACT-R (pronounced /ˌækt ˈɑr/; short for "Adaptive Control of Thought—Rational") is a cognitive architecture mainly developed by John Robert Anderson and Christian Lebiere at Carnegie Mellon University. Like any cognitive architecture, ACT- ...
), these processing centers have been identified with corresponding cortical regions in the human brain. Performing specific task, such as reading or driving, requires the simultaneous contribution of many of such regions.
Notably, 4CAPS differs from other architectures for its stress on the capacity constraints (that is, limited computational power), and the dynamic collaboration between different centers. In particular, according to Just and Varma,
4CAPS is based on four characteristic assumptions:
# Each cortical area can perform multiple cognitive functions
# Each cortical area has a limited capacity of computational resources
# The cortical network of regions that is responsible for carrying out a particular task changes dynamically as the regions' capacity resources are saturated.
# Communications between cortical regions is also subject to specific constraints, similar to bandwidth limitations along information channels.
Implementation and Applications
Like other cognitive architectures (such as
ACT-R
ACT-R (pronounced /ˌækt ˈɑr/; short for "Adaptive Control of Thought—Rational") is a cognitive architecture mainly developed by John Robert Anderson and Christian Lebiere at Carnegie Mellon University. Like any cognitive architecture, ACT- ...
, EPIC, and
Soar), 4CAPS is implemented as a
production system.
It is written in the
Common Lisp
Common Lisp (CL) is a dialect of the Lisp programming language, published in ANSI standard document ''ANSI INCITS 226-1994 (S20018)'' (formerly ''X3.226-1994 (R1999)''). The Common Lisp HyperSpec, a hyperlinked HTML version, has been derived fro ...
programming language. This system has been used to create computational models for a variety of phenomena, especially in the field of cognitive neuroscience. In particular, 4CAPS models have been created and used to fit behavioral and imaging data for tasks such as the Tower of London,
[Newman, S. D., Carpenter, P. A., Varma, S., & Just, M. A. (2003). Frontal and parietal participation in problem solving in the Tower of London: fMRI and computational modeling of planning and high-level perception. ''Neuropsychologia'', ''41'', 1668-1682.] mental rotation,
and dual-tasking.
References
* Just, M. A., & Varma, S. (2007). The organization of thinking: What functional brain imaging reveals about the neuroarchitecture of complex cognition. ''Cognitive, Affective and Behavioral Neuroscience'', ''7(3)'', 153-191.
External links
* http://www.ccbi.cmu.edu/4CAPS/index.html, The 4CAPS page at Marcel Just's laboratory website.
Notes
{{DEFAULTSORT:4caps
Common Lisp (programming language) software
Cognitive architecture