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IDA: A Cognitive Agent Architecture
Lisa Soros
Outline
Machine Consciousness Global Workspace Theory IDA: A Cognitive Agent Architecture
Machine Consciousness
Machine Consciousness
May 2001: Swartz Foundation sponsors a workshop at the Banbury Center in Long Island called 'Can A Machine Be Conscious?'
Attended by 20 psychologists, computer scientists, philosophers, physicists, neuroscientists, engineers, and indutrialists.
After the workshop, all but one attendee agreed that a machine could be conscious.
Machine Consciousness
Assuming a machine could be conscious, how could we make it so?
First, we need a model of consciousness in general.
Machine Consciousness
3 major theories of consciousness: 1. Dennett's Multiple Drafts Theory 2. Shanon's Theory 3. Baar's Global Workspace Theory
While each model has its idiosyncrasies, all assume that consciousness is not unitary in nature.
Global Workspace Theory
Global Workspace Theory
Theorized by Bernard Baars, a former Senior Fellow in Theoretical Neurobiology at The Neurosciences Institute (La Jolla, CA) in 1988
Emerged from the cognitive architecture tradition pioneered by Alan Newell and Herbert Simon (who won the Turing Award in 1975 for their contributions to AI and the psychology of human cognition)
Newell et al showed the utility of a global workspace in managing complex knowledge sources
Global Workspace Theory
According to GWT, The function of consciousness is to broadcast
information to separate functional modules throughout the brain
The global workspace is a central processor which contains the contents of consciousness
The global workspace functions as a sort of cognitive blackboard
Global Workspace Theory
Baars explains his theory using the metaphor of a theatre of consciousness:
Working memory provides the ”stage” of consciousness
Executive guidance directs the ”spotlight” of attention on the stage
The rest of the theater (small, special purpose, independent processes) is dark and unconscious
IDA: A Cognitive Agent Architecture
IDA: A Cognitive Agent Architecture
Developed by Stan Franklin and the 'Conscious' Software Research Group at the University of Memphis
Franklin's work on 'conscious' software agents has produced ~60 academic publications
After receiving his Ph.D. from UCLA, he has been on the faculty at UF, the Indian Institute of Technology at Kanpur, Carnegie Mellon, and the University of Memphis
IDA: A Cognitive Agent Architecture
IDA: Intelligent Distribution Agent Designed to serve as a detailer for the U.S.
Navy Communicates with sailors via natural language
e-mails to negotiate new assignments after their tours of duty
Must also adhere to ~90 Navy policies, fulfill job requirements, keep moving costs down, and respond to the wishes of the sailors
IDA: A Cognitive Agent Architecture
IDA: A Cognitive Agent Architecture
Codelet – a special purpose, relatvely independent mini-agent typically implemented as a small piece of code running as a separate thread (Hofstadter)
Perceptual codelets, attention codelets, information codelets, behavior codelets, language generation codelets...
Codelets in IDA correspond with processors in GWT
IDA: A Cognitive Agent Architecture
IDA: A Cognitive Agent Architecture
Perception Consists mostly of input from e-mails Uses only surface-level NLP (no parsing) Uses a Copycat-like architecture (Hofstadter &
Mitchell) with perceptual codelets triggered by both e-mail content and internal knowledge
This allows IDA to recognize, categorize, and understand
IDA: A Cognitive Agent Architecture
”A secretary sending out an email announcement of an upcoming seminar on Compact Operators on Banach Spaces can be said to have understood the organizer’s request that she do so even though she has no idea of what a Banach pace is much less what compact operators on them are. In most cases it would likely require person years of diligent effort to impart such knowledge. Nonetheless, the secretary understands the request at a level sufficient for her to get out the announcement. In the same way IDA understands incoming email messages well enough to do all the things she needs to with them.” - Franklin
IDA: A Cognitive Agent Architecture
Workspace Corresponds to the Working Memory (or STM) in
humans Consists of registers set aside for particular
categories of information Perceptual & internal codelets write to the
workspace, while many other codelets are watching the workspace in case they need to react to it
Interfaces with LTM; some, but not all, workspace contents are written to associative memory
IDA: A Cognitive Agent Architecture
Associative Memory SDM – Sparse Distributed Memory, a content-
addressable memory Writing to the workspace cues activation and
retrieval in the associative memory
IDA: A Cognitive Agent Architecture
IDA: A Cognitive Agent Architecture
'Consciousness' mechanism A coalition manager, a broadcast manager, a
spotlight controller, and attention codelets (which bring appropriate contents to 'consciousness')
Attention codelets watch out for items that might require 'conscious' attention
When attention-worthy items are found, the information codelets that describe the item are gathered into a coalition to handle the situation
The coalition then competes for the spotlight of 'consciousness'
IDA: A Cognitive Agent Architecture
Example: An attention codelet recognizes the please-find-job
message type It gathers information codelets carrying the sailor's
name and SSN in addition to the message type The attention and information codelets form a
coalition and compete for 'consciousness' If successful, the coalition's contents are broadcast
to the rest of the system
IDA: A Cognitive Agent Architecture
Behavior Selection (Decision Making) Behavior net: Several drives acting in parallel,
which vary in urgency with time and the environment
Behaviors depend on many behavior codelets Behaviors are like production rules, with
preconditions, additions, and deletions In the behavior net, behaviors spread activations to
other behaviors
IDA: A Cognitive Agent Architecture
Other modules: Emotion Deliberation Constraint Satisfaction Voluntary Action Negotiation Learning Metacognition