Читать книгу Figure It Out - Stephen P. Anderson - Страница 19

The computational theory of mind has a straightforward model of cognition built around four parts: the external world, perception, cognition, and action. These form a loop, as shown in Figure 2.1. Under this model, we perceive information from the world through our senses, which our brain converts into mental representations. This is followed by cognition proper (mental computation on mental representations), which, in turn, leads to acting on the world. Then the cycle begins anew with more perception, cognition, action, and so forth.

FIGURE 2.1 The basic structure of human cognition according to the computational theory of mind. Although grossly simplified, it captures the essential features of the standard model.

The most notable features of this model are that it’s sequential—first one thing, then another—and that cognition happens in the head. Perception serves as the input to cognition, and the output is action on the world. The starring role in the cognitive drama goes to brain-based processes (i.e., mental computation). Anything that happens outside the skull is secondary, merely part of the supporting cast.

This brain-centered view of human thinking forms the foundation for many models of human cognition. One of the most influential models is the Model Human Processor, which was developed in the early 1980s as the cognitive revolution was in full swing. This model divides the mind into three main parts: perception (for converting sensory input into mental representations), cognition (for mental computation and memory), and motor control (for moving the body).⁸ In other words, perception is input, cognition happens in the brain, and action is output, just like the diagram in Figure 2.1.

Other cognitive models share a similar structure. Consider EPIC, which was developed to model how human beings interact with computers.⁹ Like the Model Human Processor, EPIC is also based on input and output mechanisms (see Figure 2.2). It describes the human body in terms so comically detached from everyday life that you can almost see the lab coats and pocket protectors.

FIGURE 2.2 The EPIC model of cognition: note how the terminology describes parts of the body in terms of inputs, outputs, and processing information. The model also omits many parts of the body—legs and feet being the most obvious.

It features an “auditory processor” instead of ears, a “vocal motor processor” instead of a mouth, and an “ocular motor processor” instead of eyes. Hands are called manual motor processors and, in an oversight that reflects a world before smartphones, the modeled human has no feet.