All wine descriptive language is in fact organized around wine types…. What a wine taster does in front of a wine is not an analysis of its separate sensory properties but a comparison of all the cognitive associations he or she has from the wine (color, initial aroma, and taste) with the impressions he or she has already experienced when tasting other wines.
There are many reports of people who can smell colors or taste sounds. Indeed, the sensory input from our ears and our olfactory systems converge in a part of the brain that is activated by sound and smell, the first step in sensory synthesis. The brain creates even more complex combinations that are at the heart of our conscious sensory experiences. It links our knowledge from our senses of taste and smell to our knowledge of where we are, using the knowledge we gain through the physical senses of touch, sound, and sight; and this synthesis is combined with our feelings and emotions, such as a sudden feeling of melancholy when we revisit a place where we suffered disappointment in the past. Indeed, the amygdala, which is the emotional center of the brain, is linked to the hippocampus, which records our spatial position. And these, as well as the olfactory cortex, are linked to the striatum, the brain region that measures the rewards we receive from specific actions in the form of feelings of pleasure and pain and uses these estimates to control our behavior—eating more, or less, for example. The result is a grand synthesis of what we are experiencing and how we feel about it—but a synthesis that is an “invention” of our brains.
Memory, and the idea of a past, a present, and a future, are also a creation of our brains. In his own way, Marcel Proust captures the synthetic quality of memory when he describes tasting his famous tea-soaked madeleine (causing a retronasal stimulation), which led to a series of childhood recollections. Just as flavor is a creation of the brain that is neither simply taste nor smell, but a synthesis primarily of both kinds of stimuli, Proust’s description of his recollection suggests (as do many studies of memory) that memories, emotions, tastes, and smells are the consequence of a broad synthesis of the sensory information the brain receives from our eyes, ears, touch, and movement receptors.
As Shepherd notes, though Proust claims that involuntary memories appear suddenly, he describes how his recollections of the village of Combray came to him gradually, after a prolonged conscious effort. Proust writes:
Undoubtedly what is thus palpitating in the depths of my being must be the image, the visual memory which, being linked to that of taste, is trying to follow it into my conscious mind…. Ten times over I must essay the task….
And suddenly the memory revealed itself.
The process of remembering is similar to processing a photograph of a face in a darkroom. The first hints of the image may not be recognizable, but little by little the face begins to appear on the photographic sheet. Suddenly we recognize the face that we see—though the face has yet to appear in its entirety. Studies of the neurophysiology of memory reveal a similar slow “development” of a recollection. We needn’t see the entirely developed image to recognize the face. The brain can construct the full image from incomplete sensory information.
Thus Combray is a construction, as are most memories—in Proust’s recollection, Shepherd writes, “a retronasal smell recalled a visual scene.” It all began with a sensation of the flavor of his madeleine dipped in tea.
Consciousness itself, like memory, is an integration of past and immediate sensory experience. We are conscious of neither the past as such nor the immediate present, but of a synthesis of past and present that, like the colors we see and the flavors we taste, is a creation of the brain. In this way, the brain stabilizes our perceptual (and mental) worlds, making them knowable and to some degree predictable.