Story of Psychology - Morton Hunt [312]
Where does all this leave us?
We have seen two richly detailed bodies of information deriving from two basic ways of explaining visual perception: the cognitive, thought-like approach and the neurological, stimulus-based approach (and perhaps, but to a lesser extent, a third one, Gibson’s “ecological” or “direct perception” theory). But these accounts of perception are not contradictory but complementary; each describes a part of the full reality. To employ a well-worn metaphor, you can describe what is happening when you type at your computer in terms of the program you are using (Word, WordPerfect, and so on); or you can describe it in terms of what takes place in the microprocessor, circuits, monitor, and other parts of the hardware. So it is with human perception: Both the cognitive and the neurophysiological approaches are sound; we can consult either one or both, depending on what we want to understand.
With so long and rich a history of studies of the cognitive aspects of perception, plus the dramatic and abundant recent findings of cognitive neuroscience, it is not surprising that the emphasis of today’s perception researchers is less on grand theory or even midrange theory than on special and rather fine-tuned topics. Any recent copy of APA’s Journal of Experimental Psychology: Human Perception and Performance makes that obvious; here, for instance, are a few titles from the April 2006 issue of that journal:
“On the Surprising Salience of Curvature in Grouping by Proximity.”
“Memory for Where, But Not What, Is Used During Visual Search.”
“Sequence Learning and Selection Difficulty.”
“Speeded Old-New Recognition of Multidimensional Perceptual
Stimuli: Modeling Performance at the Individual-Participant and Individual-Item Levels.”
“Eye Movements and Lexical Ambiguity Resolution: Investigating the Subordinate-Bias Effect.”
“The Beneficial Effects of Additional Task Load, Positive Affect, and Instruction on the Attentional Blink.”
But we need not concern ourselves further with this level of research. We have seen enough to know that perception, despite its remaining puzzlements, is now a relatively developed area of psychological knowledge. We know a great deal more about perception than has been known up to now—but also know that far more remains to be known. For as Michael Gazanniga and Todd Heatherton sum up the situation, “the big puzzle that occupies the minds of modern psychological scientists is unraveling the nature of the connection between electrochemical activity within the neural circuits and the complex information processing that culminates in our perception of the world.”88
Or to put it simplistically: How do our neural processes become us?
* Since most of the psychological research on perception has concerned vision, we will bypass the other senses.
† In this chapter we will touch only lightly on cognitive neuroscience but come to grips with it in a later chapter.
* Some perception researchers attribute the reversal effect to neural satiation (the retinal neurons become fatigued with one image and the other replaces it). But this does not explain why we can switch images at will.
FIFTEEN
The Emotion
and Motivation Psychologists
Fundamental Question
If you were to stand on the bank of some quiet estuary of a Long Island bay on a spring day, you might be lucky enough to see a female muskrat swimming desperately and uttering anguished yelps as a male muskrat paddles furiously after her. (He invariably catches her, or perhaps she invariably allows him to.) If you were to sit on a deserted Long Island beach in spring, you might see a male sea gull furiously chase away a female gull