Cognitive Modeling Cogs 4961, Cogs 6967 Psyc 4510 CSCI 4960 Mike Schoelles

Cognitive Science Cognitive ?? –Complex representations and computational procedures Levels of Analysis (David Marr) –Computational –Algorithmic –Implementation Functionalism

Mind

“How do brain processes give rise to mind?” J. McClelland “How does the brain think?” Randy O’Reilly “Minds are simply what brains do” Marvin Minsky “The Astonishing Hypothesis is that “You,” your joys and your sorrows, your memories and your ambitions…and free will are in fact no more than the behavior of a vast assembly of neurons…” Fraincis Crick “How can the mind exist in the physical universe?” John Anderson

Brain -> Mind Brain is made of neurons –Not enough, need explanation How billions of interacting neurons produce (embodied) Cognition Need computational approach Simulations to explain complex phenomenon

Unified Theories of Cognition Account of intelligent behavior at the system-level Newell’s claim –“You can’t play 20 questions with nature and win” “a single set of mechanisms for all of cognitive behavior”

Newell’s Time Scale of Human Activity

Newell’s Time Scale of Human Activity (amended)

What is a Cognitive Architecture ? A blueprint for intelligent agents. It proposes (artificial) computational processes that act like certain cognitive systems, most often, like a person, or acts intelligent under some definition –Wikipedia Infrastructure for an intelligent system –Cognitive functions that are constant over time and across different task domains –Pat Langley, John Laird, Seth Rogers Analogous to a building, car, or computer

What is a Cognitive Architecture? A specification of the structure of the brain at a level of abstraction that explains how it achieves the function of the mind –Anderson Brain  Cognitive Architecture  Mind Architecture + Knowledge => Behavior

Integrated Cognitive Architecture Cognition does not function in isolation –Interaction with perceptual and motor systems Embodied cognition –Represents a shift from “mind as an abstract information processing system” Perceptual and motor are merely input and output systems –Other body processes – lacking Effects of caffeine, stress and other moderators Emotions Extended cognition –Must consider the role of the environment –Cognition extends into the world –Interaction with environment Andy Clark

Try to estimate…. Time to move eyes from middle of screen to start menu (PC) File menu (MAC) Time to move cursor from middle of screen to start or file menu. Time to recognize the word “start” or “file” Time to retrieve name of the building for this class Time to retrieve name of the building of 1 st class yesterday How many words per minute do you speak How long to press a key on keyboard

Alternatives to Cognitive Architectures Classic Information Processing Psychology –Ignore the Brain Eliminative* Connectionism –Ignore the Mind Bayesian Approach –Ignore the Architecture

Why Cognitive Architectures? Idea testing –Understanding and explanations Deal with complexity –Span levels Explicit –Make predictions Control –Can look at inner workings –Explore causal control

Why Cognitive Architectures? Common Language –E.g. “Attention” Process models –Interact with environment –Context

Why not? Too simple Assumptions not warranted by data –Modeler must show how model uses principles to account for data Can model anything –Free parameters –What is the correct model Indeterminacy problem

What is Cognitive Modeling The program written in the language of a cognitive architecture –Do a task –Learn Modeler adds the knowledge

Applications for a Cognitive Architecture Psychology – Predict experimental outcomes –Account for experimental data Human Computer Interaction –Evaluate interface design –Usability testing Games –Cognitive Agents –Computer Generated Forces Robotics Education –Intelligent Tutoring Systems Philosophy –Provide a unified understanding of the mind

Models X-Plane Games –SET –SUDOKU Space Fortress