Cognitive Science-a bit of history and perspectives

The intellectual developments that paved the way for Cognitive Science began in the 1940s and 1950s. The most significant events were outgrowths of the conceptual invention (via mathematical description) of computer machines by the British mathematician, Alan Turing, in 1950. The first digital computers -- also known as "universal Turing machines" -- were built shortly thereafter. Turing and others soon realized that these computers could be programmed to perform complex "intellectual" tasks previously performed only by humans, tasks such as playing chess, proving mathematical theorems, and understanding language.

Pioneers in this new field of computer science began to make progress toward these goals by programming computers to simulate mental processes. For example, Allen Newell and Herbert Simon's famous program, the General Problem Solver (GPS), was able to play chess and to prove theorems remarkably well for a program written in the early 1960s. Understanding natural language has proven to be a more difficult task, but progress is also being made in that domain. Surprisingly, the supposedly "simple" process of perceiving the visual world, which is not a uniquely human capability at all, has turned out to be among the hardest capabilities to simulate in computers. Current research in computer science is aimed at further progress in all of these domains.

In response to this enterprise -- dubbed "artificial intelligence" by its practitioners -- philosophers began to formulate a new approach to the age-old problem of the relation between mind and brain. Their idea was to explore a particular analogy suggested by the work in artificial intelligence: that mind is to brain as program is to computer. Thus was born the notion that minds are essentially "program like" entities that "run" on brains instead of computers. This proposal spawned a major philosophical debate about the nature of mental events. It centered on new issues, such as whether a computer could really "understand" language or really "have" conscious experiences as the result of running the right program, as some believed and others disputed. This debate is on-going, with Berkeley philosophers Searle and Dreyfus playing central roles in the dispute.

The closely related idea that mental activity could be described as information processing emerged in psychology at about the same time. This was partly due to the direct influence of work in artificial intelligence, especially via Newell and Simon's proposal that a computer program was a psychological theory of how people performed the task it simulated. Other psychologists were also exploring information processing as a way to break the grip of Behaviorism on psychology. The behaviorists, who had dominated psychology for decades, claimed that the only proper object of study for scientific psychology was overt behavior, thus ruling out any reference to internal mental states. The information processing approach stated that mental events could be described as a structure of operations for constructing and transforming internal representations and gave a principled way in which internal events could be specified rigorously and tested scientifically. As a result of the paradigm shift often referred to as the "cognitive revolution," information processing has now replaced Behaviorism as the dominant force in psychology.

Related ideas were also revolutionizing the field of linguistics at about the same time. The publication of Noam Chomsky's influential book, Syntactic Structures, in 1957 marked the birth of this movement. He proposed a transformational approach to grammar in which the "surface structure" of sentences was derived from an underlying "deep structure" of primitive linguistic units by a series of rules or transformations. The formal structure of these transformations was closely related to finite state automata in computational theory and to the information processing approach in psychology. Chomsky has now revised his theory several times, and others have developed competing approaches, including "cognitive linguistics".

During the same period, new techniques were being pioneered in neurophysiology that allowed scientists to begin to understand the workings of the brain as an information processing device. For example, new methods of staining individual neurons showed how they projected from one area of the brain to another, allowing anatomists to map out the large-scale "wiring diagram" of certain brain regions. Even more importantly, neurophysiologists developed methods for recording the activity of individual brain cells. This technique allowed Nobel Laureates David Hubel and Thorsten Wiesel to determine the patterns of retinal stimulation that caused cells in visual cortex to fire. Several decades of work building on their pioneering studies have increased our understanding of the physiological mechanisms underlying vision which serves as a model for other areas of the brain.

More recent advances in physiology have come from various brain scanning and imaging techniques, such as computer-assisted tomography (CT), magnetic resonance (MR), and positron emission topography (PET) methods. These have allowed human brains to be studied in ways heretofore impossible. For example, scientists can now identify specific regions of brain damage in neurological patients so that symptoms can be correlated with anatomical location. Using these methods in conjunction with those of cognitive psychology, cognitive neuroscientists are beginning to map out the function of major areas of the human brain.

During the 1970s, researchers in different fields started to recognize the relevance of work in neighboring disciplines and to learn something about it. This interaction marked the true birth of Cognitive Science as a scientific endeavor. Important milestones in the history of this movement were the founding of Society for Cognitive Science in 1979, the funding of a large-scale program by the Sloan Foundation in 1981 and the foundation of the journal Cognitive Science in 1977. In the intervening years, programs and departments of Cognitive Science have been established at major American universities at both the undergraduate and graduate levels. Cognitive Science is now well on its way toward becoming an independent and interdisciplinary academic discipline.