Cognitive Revolution

A recap of Kuhn • Normal science is defined by a paradigm. • Normal science and research are dedicated attempts to force nature into the conceptual boxes provided by the paradigm. • Revolution! A new paradigm replaces the old when it accounts for the anomalies and previous findings of the old paradigm, and proposes new questions for the conduct of normal

Revolutions in Psychology? •

Structuralism o What are the elements-basic structures--of conscious experience? o Introspection

2. Behaviorism o How does the environment shape behavior? o Experimentation (animals)

Revolutions in Psychology? Emerging challenges to Behaviorism: Gestalt Psychology

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The whole is greater than the sum of its parts. Humans have highly integrated and organized cognitive structures with which they interpret the world.

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Emerging challenges to Behaviorism Neuropsychology o Karl Lashley, Donald Hebb o How are complex behaviors such as musical performance or language made possible by behaviorist principles? o The brain is an active, dynamic, central organizer of behavior. Behavior is not passively stimulated by the environment. (Organismic vs

Emerging challenges to Behaviorism The Computer and Information Age! Logico-Mathematical Precursors: Boolean Algebra (eh?) George Boole (1854) Proposed that thought processes can be represented within a system of logic, using abstract symbols Symbols as binary truth values (i.e., true/false)

Emerging challenges to Behaviorism Logico-Mathematical Precursors: The Turing Machine Alan Turing (1936) Designed a hypothetical machine that uses an infinite number of binary symbols (0/1 or blank/slash) to be able to execute ANY program or function.

This is the precursor of the digital computer!

The implication is that machines could be programmed to do anything with a set of rules expressed in symbols. QuickTimeª and a TIFF (Uncompressed) decompressor are needed to see this picture.

One day ladies will take their computers for walks in the park and tell each other, ‘My little computer said such a funny thing this morning!’ ~ Alan Turing (?)

Such a machine could embody the notion that thinking is a computational process… …and Voila! A new way of understanding human intelligence is born!

What does this mean? This means that to the extent that the world obeys mathematical equations that can be solved step by step, a machine can be built that simulates the world and makes predictions about it. To the extent that rational thought corresponds to rules of logic, a machine can be built that carries out rational thought. To the extent that a language can be captured by a set of grammatical rules, a machine can be built that produces grammatical sentences. To that extent that thought consists of applying any set of well-specified rules, a machine can be

Emerging challenges to Behaviorism Cybernetics (Control & Communications Engineering) Development of servomechanisms: devices which kept planes and missiles on course via planful, goal-oriented, self-corrective (feedback) systems

These developments reverberated in Psychology and revived interest in the study of the “mind”! • Thinking can be “automated” and carried out by machines. • Information and information-processing could be represented as abstractions or symbols. • Patterns of thinking could be described as “programs” based on some symbolic representation (i.e., software).

The Rise of the Cognitive Metatheory Birthday: 1955-1960 Psychology is the scientific study of mental, representational constructs and processes such as: Thinking Problem-solving Images Schemas Concepts Perceptions Beliefs Goals

The Cognitive Metatheory • Assume that humans are active information-processors, goal-oriented, and responsive to feedback from the environment. • Concerned with studying how information is represented and processed to produce behavior.

Key Features of Cognitive Science 1. Mental representations as a core assumption o Human cognitive activity is described and explained in terms of symbols, rules, images, propositions, and the like

Key Features of Cognitive Science 1. The computer as a model of human mental processes o The computer as “existence proof”: if a machine can be said to be “intelligent” when manipulating symbols in rule-based ways, then so can humans be descibed o Computational theory of the mind: symbols can carry meaning and cause some chain of events to

Key Features of Cognitive Science 1. De-emphasis on affect, culture, and history o But changing: call for an ecologically valid cognitive psychology which considers theories and models about the tasks, issues, and problems that humans encounter in everyday life