When I hear a car horn, air molecules impinging on my eardrum cause electrical signals to be sent to my auditory cortex. This causes a cascade of events that recruits a very different group of neurons than toe stubbing. First, neurons in the auditory cortex process the pitch of the sound so that I can distinguish the car horn from something with a different pitch like a truck’s air horn, or the air-horn-in-a-can at a football game. A different group of neurons is activated to determine the location from which the sound came. These and other processes invoke a visual orienting response—I turn toward the sound to see what made it, and instantaneously, if necessary, I jump back (the result of activity from the neurons in my motor cortex, orchestrated with neurons in my emotional center, the amygdala, telling me that danger is imminent). When I hear Rachmaninoff’s Piano Concerto no. 3, the hair cells in my cochlea parse the incoming sound into different frequency bands, sending electrical signals to my primary auditory cortex—area A1— telling it what frequencies are present in the signal. Additional regions in the temporal lobe, including the superior temporal sulcus and the superior temporal gyrus on both sides of the brain, help to distinguish the different timbres I’m hearing. If I want to label those timbres, the hippocampus helps to retrieve the memory of similar sounds I’ve heard before, and then I’ll need to access my mental dictionary—which will