Steven Pinker -- How the Mind Works - Hampshire High Italian ...

286 HOW THE MIND WORKSImagery is an industry. Courses on How to Improve Your Memoryteach age-old tricks like imagining items in the rooms of your house andthen mentally walking through it, or finding a visual allusion in a person'sname and linking it to his face (if you were introduced to me, you wouldimagine me in a cerise leisure suit). Phobias are often treated by a kindof mental Pavlovian conditioning where an image substitutes for the bell.The patient relaxes deeply and then imagines the snake or spider, untilthe image—and, by extension, the real thing—is associated with therelaxation. Highly paid "sports psychologists" have athletes relax in acomfy chair and visualize the perfect swing. Many of these techniqueswork, though some are downright flaky. I am skeptical of cancer therapiesin which patients visualize their antibodies munching the tumor,even more so when it is the patient's support group that does the visualizing.(A woman once called to ask if I thought it would work over theInternet.)But what is a mental image? Many philosophers with behavioristleanings think the whole idea is a terrible blunder. An image is supposedto be a picture in the head, but then you would need a little man etcetera, et cetera, et cetera. In fact, the computational theory of mindmakes the notion perfectly straightforward. We already know that thevisual system uses a 2 l h-D sketch which is picturelike in severalrespects. It is a mosaic of elements that stand for points in the visualfield. The elements are arranged in two dimensions so that neighboringelements in the array stand for neighboring points in the visual field.Shapes are represented by filling in some of the elements in a patternthat matches the shape's projected contours. Shape-analysis mechanisms—notlittle men—process information in the sketch by imposingreference frames, finding geons, and so on. A mental image is simply apattern in the 272-D sketch that is loaded from long-term memory ratherthan from the eyes. A number of artificial intelligence programs for reasoningabout space are designed in exactly this way.A depiction like the 2V2-D sketch contrasts starkly with a descriptionin a language-like representation like a geon model, a semantic network,a sentence in English, or a proposition in mentalese. In the propositionA symmetrical triangle is above a circle, the words do not stand for pointsin the visual field, and they are not arranged so that nearby words representnearby points. Words like symmetrical and above can't be pinned toany piece of the visual field; they denote complicated relationshipsamong the filled-in pieces.