Read Iconoclast: A Neuroscientist Reveals How to Think Differently for Free Online

processing mode to global processing and makes judgments of object identities and their locations in space. As you might imagine, it is an incredibly complex feat to perform. Only the most powerful computers can perform the task of identifying objects and cross-reference them with a catalog of labels and images from memory. Although it is a trivial task for you to distinguish an automobile from a bicycle, no matter from which direction you see them, a computer would have a great deal of difficulty doing this. Both objects have wheels, yet they may not be visible when the objects are viewed from behind. Imagine the even more complex task of how we distinguish different people from one another. Everyone has the same basic anatomy, and yet we are able to identify people, sometimes from extreme angles in which we don’t even see their face full on.
    The ability to perform such complicated perceptual functions comes with a price. Evolution has resulted in a human brain that can accomplish amazing perceptual tasks, all the while saving energy. The need to distinguish friend from foe, or predator from prey, and to do it quickly enough to decide whether to run or fight, meant that the brain had to take shortcuts and make assumptions about what it was seeing. From the earliest levels of processing in the visual system, the brain extracts useful pieces of information and discards others. Depending on which road the information takes, the bits retained or discarded may be different. The high road is concerned with extracting where objects are located and throws away the elements related to their identity. The low road, on the other hand, is concerned with identification and categorization, and less so with objects’ spatial locations.
    Although the spatial location of what we see may be important, most of what iconoclasts do differently from other people lies in howthey categorize what they see. Whether one person sees ugliness or beauty in asymmetry is entirely a result of categorization. In the same way, whether an NMR spectrum is viewed as noisy or full of extra information doesn’t come from the image itself, but in the way the viewer categorizes the image. For this reason, understanding how the low road pigeonholes objects into categories suggests ways out of predictable perception.
    As in playing the game 20 Questions, the first, and most salient, decision the brain makes is whether it is viewing a person or something else. People constitute a special category of objects. The high degree of social interaction, both at the level of facial and body expression and in the use of language, dictates that the brain treats people differently than anything else. So specialized is this function, neuroscientists have identified the precise location in the brain that responds to human faces. If we were to examine the brain from its underside, the temporal lobes would fan out like butterfly wings. The innermost portion of the lower wings contains neurons that respond only to faces and is called the
fusiform face area
, or FFA. Some of these neurons perform highly specialized functions and seem to be active only when viewing a face from a particular angle. Many years ago neuroscientists hypothesized that the level of specialization might go so deep that neurons might exist that responded to one thing, and one thing only. These hypothetical neurons were dubbed
grandmother cells
, because you might have neurons that fired only when you saw your grandmother. A great deal of specialization does exist in the FFA, although not to this degree (which is probably a good thing, because if your hypothetical grandmother cell became damaged, then you wouldn’t be able to recognize your grandmother anymore). Most aspects of facial processing appear to be carried out by a network of neurons in the FFA. 8 This type of architecture is called
distributed processing
and is yet another example of how the brain efficiently organizes information. Because