We Know It When We See It: What the Neurobiology of Vision Tells Us About How We Think

Masland, a Harvard Medical School neuroscience professor, misses the mark in this attempt to explain vision’s neurobiological basis to a general audience. He does a very good job of explaining how perception broadly, including vision, works, and even those without any grounding in the fundamentals of biology will be able to gain an appreciation of how the nervous system interacts with the outside world and conveys information to the brain. What works less well is the complexity that intrudes as Masland moves beyond the basics (“If the axons of the retinal ganglion cells synapse upon the neurons of the lateral geniculate nucleus...”), making it unlikely that his target audience will stay with him. His forays into comparing the ways brains process visual stimuli with the ways in which artificial intelligence attempts to accomplish the same task are intriguing but abbreviated, as is his almost fleeting discussion of the nature of consciousness, in which he concludes, “In the end I fear that consciousness is unknowable.” Those looking for a scientific explanation of vision will find a useful primer, but those searching for answers to larger questions, such as the one posed by Masland’s subtitle, are likely to be disappointed. (Mar.)