Image courtesy of MIT Press

by Daniel Fink, MD, Chair, The Quiet Coalition

The phrase “of sound mind” is in the New Testament, but it came to have the legal meaning of “that state of a person’s mind which is adequate to reason and comes to a judgment upon ordinary subjects, like other rational people.”

But that’s not the meaning Northwestern University Prof. Nina Kraus has in mind in her wonderful new book, “Of Sound Mind.” Prof. Kraus summarizes what she and others have learned about how our brain constructs a meaningful sonic world. For her, the “sound mind” is the hearing brain, that part of the brain that processes what the ear perceives and transmits to the brain.

My focus on noise has generally stopped once the electrical signals generated by sound waves moving the tympanic membrane (ear drum) reach the eighth cranial nerve, i.e., the auditory nerve, so it was fascinating to learn more about how the brain processes sound.

For example, I didn’t understand how much the brain controls how sound is heard and processed by efferent signals to the ear and various nuclei–processing way stations in the neural pathways for sound from the ear to the brain and back–so that what we hear in the brain, in the auditory processing cortex, is finely modulated. Prof. Kraus also discusses the importance of music for the brain and the connections between music, movement, and emotion.

It’s been decades since I wrote a book review, and space considerations for a blog post preclude my doing that here, but I recommend “Of Sound Mind” highly.

This 9-minute interview with NPR’s Ari Shapiro ‘Of Sound Mind’: Nina Kraus Explains The Science Of Brains is well worth listening to.