Story of Psychology - Morton Hunt [368]
As is the case with other sciences, the proliferation of hypotheses and collecting of empirical evidence by cognitive psychologists has often produced corrections and drastic revisions of theories, minitheories, and data, but seen in perspective, cognitive psychology has been a cumulative, self-correcting, self-transforming science.
Its one great shortcoming has always been its lack of an adequate explanation of how the activity of billions of neurons in the brain can result in thoughts, emotions, and voluntary actions. As the neuropsychologist V. S. Ramachandran and science writer Sandra Blakeslee wrote a few years ago, “Many people find it disturbing that all the richness of our mental life—all our thoughts, feelings, emotions, even what we regard as our intimate selves—arise entirely from the activity of little wisps of protoplasm in the brain. How is this possible? How could something as deeply mysterious as consciousness emerge from a chunk of meat inside the skull?”113
In an effort to answer this question, ever since the early days of the cognitive revolution many psychologists have reached beyond the classic boundaries of their field to explain what they were studying in terms of hormonal, genetic, and other physiological factors. And for the past two and a half decades, as we have seen throughout this chapter, many psychologists have turned to the methods of cognitive neuroscience, especially brain scanning, to help validate their psychological hypotheses. But valuable as all this is, it still does not tell us how a blizzard of neural impulses becomes thought or other mental processes.
Cognitive neuroscience, especially since the advent of brain scans, has been compiling a record of advances in knowledge as impressive as that of cognitive psychology. The neuroscientists have traced neuronal pathways from sense receptors to various loci in the brain, located the areas where emotions are generated, shown that memories are stored in distributed network fashion, and in general extended their research deep into the territory of cognitive psychology, amassing a great deal of information about what areas of the brain are active in mental imagery, attention, speech, learning, voluntary and involuntary action, and other areas of classic psychological interest.
All of which is impressive and almost certainly will be the foundation on which some day a fuller explanation of how the brain becomes mind may be forthcoming. But not yet. The authors of one impressive tome of neuroscience write, “In this book, we explore how the brain actually does enable mind”114—but by “enable” they seem to mean something less than explain how the synaptic events become mental events. I asked Martha Farah, director of the Center for Cognitive Neuroscience at the University of Pennsylvania, if the problem were not akin to that of trying to account for the movement of a wave in terms of the movements of individual molecules of water; she laughed and said, “Fluid mechanics is independent of molecular physics. But cognition may not be describable without some details of neuronal function being in the picture.”
Thus, a mental process as simple as a word retrieved from memory cannot be equated with the firing of millions of neurons and the resultant billions of synaptic transmissions but is the product of the pattern or structure of those firings and transmissions. Mental phenomena such as speech, memory retrieval, and reasoning are governed not by the laws of neural activity but by those of cognitive psychology. The former