UNTHINKABLE

A user-friendly tour of the brain and the curious things that go on inside of it, from splendidly practical visions to debilitating hallucinations.

The brain is inseparable from the body, even if, writes New Scientist writer and consultant Thomson, “all too often we think about our brains as being somehow separate from ourselves.” Of course, the concept of “ourselves” is not uniform: We see broad variations in the capabilities and workings of the brain, from normal to abnormal and all points between. Some of the most extraordinary brains aren’t particularly interesting in the thoughts that they generate; one of Thomson’s case studies possesses what is called “highly superior autobiographical memory,” by which a person can recall just about every detail of every moment he has lived. There’s a reason we forget, of course: It’s an evolutionary adaptation that enhances survival so that we pay attention to the oncoming lion or truck rather than being constantly enthralled by lingering memories. “The brain doesn’t tolerate inactivity,” the late Oliver Sacks told Thomson in an interview. Indeed, the brain makes inventive use of its resources; thus it is that some people associate particular colors, musical notes, or even tastes with particular words, which is sometimes a blessing and sometimes a curse. Thomson introduces a lot of good neuroscience lightly, explaining how we perceive reality, such as it is (one of her informants calls reality “a controlled hallucination, reined in by our senses”), and check in with ourselves (“our ability to sense the physical condition of our body is called interoception”). A bonus, along the way, are the author’s notes on such things as improving memory skills through the construction of memory palaces and other event-fixing tricks and training the brain how not to get lost, a highly useful skill indeed.

Pleasing and accessible and of broader application than the title suggests, inasmuch as “we all have an extraordinary brain.”