The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human

To this model I’d add the notion that each time a partial fit is discovered, a small “Aha!” is generated in your brain. This signal is sent to limbic reward structures, which in turn prompt the search for additional, bigger “Ahas!,” until the final object or scene crystallizes. In this view, the goal of art is to create images that generate as many mutually consistent mini-“Aha!” signals as possible (or at least a judicious saturation of them) to titillate the visual areas in your brain. Art in this view is a form of visual foreplay for the grand climax of object recognition.

The law of perceptual problem solving, or peekaboo, should now make more sense. It may have evolved to ensure that the search for visual solutions is inherently pleasurable rather than frustrating, so that you don’t give up too easily. Hence the appeal of a nude behind semitransparent clothes or the smudged water lilies of Monet.¹

The analogy between aesthetic joy and the “Aha!” of problem solving is compelling, but analogies can only get us so far in science. Ultimately, we need to ask, What is the actual neural mechanism in the brain that generates the aesthetic “Aha!”?

One possibility is that when certain aesthetic laws are deployed, a signal is sent from your visual areas directly to your limbic structures. As I noted, such signals may be sent from other brain areas at every stage in the perceptual process (by grouping, boundary recognition, and so on) in what I call visual foreplay, and not just from the final stage of object recognition (“Wow! It’s Mary!”). How exactly this happens is unclear, but there are known anatomical connections that go back and forth between limbic structures, such as the amygdala, and other brain areas at almost every stage in the visual hierarchy. It’s not hard to imagine these being involved in producing mini-“Ahas!” The phrase “back and forth” is critical here; it allows artists to simultaneously tap into multiple laws to evoke multiple layers of aesthetic experience.

Back to grouping: There may be a powerful synchronization of nerve impulses from widely separated neurons signaling the features that are grouped. Perhaps this synchrony itself is what subsequently activates limbic neurons. Some such process may be involved in creating the pleasing and harmonious resonance between different aspects of what appears on the surface to be a single great work of art.

We know there are neural pathways directly linking many visual areas with the limbic structures. Remember David, the patient with Capgras syndrome from Chapter 2? His mother looks like an imposter to him because the connections from his visual centers and his limbic structures were severed by an accident, so he doesn’t get the expected emotional jolt when seeing his mom. If such a disconnection between vision and emotion is the basis of the syndrome, then Capgras patients should not be able to enjoy visual art. (Although they should still enjoy music, since hearing centers in their cortices are not disconnected from their limbic systems.) Given the rarity of the syndrome this isn’t easy to test, but there are, in fact, cases of Capgras patients in the older literature who claimed that landscapes and flowers were suddenly no longer beautiful.

Furthermore, if my reasoning about multiple “Ahas!” is correct—in that the reward signal is generated at every stage in the visual process, not just in the final stage of recognition—then people with Capgras syndrome should not only have problems enjoying a Monet but also take much longer to find the Dalmatian dog. They should also have problems solving simple jigsaw puzzles. These are predictions that, to my knowledge, have not been directly tested.

Until we have a clearer understanding of the connections between the brain’s reward systems and visual neurons, it’s also best to postpone discussing certain questions like these: What’s the difference between mere visual pleasure (as when seeing a pinup) and a visual aesthetic response to beauty? Does the latter merely produce a heightened pleasure response in your limbic system (as the stick with three stripes does for the gull chick, described in Chapter 7), or is it, as I suspect, an altogether richer and more multidimensional experience? And how about the difference between the “Aha!” of mere arousal versus the “Aha!” of aesthetic arousal? Isn’t the “Aha!” signal just as big with any old arousal—such as being surprised, scared, or sexually stimulated—and if so, how does the brain distinguish these other types of arousal from a true aesthetic response? It may turn out that these distinctions aren’t as watertight as they seem; who would deny that eros is a vital part of art? Or that an artist’s creative spirit often derives its sustenance from a muse?