How Selective Hearing Works in the Brain: 'Cocktail Party Effect' Explained
The longstanding mystery of how selective hearing works -- how people can tune in to a single speaker while tuning out their crowded, noisy environs -- is solved this week in the journal Nature by two scientists from the University of California, San Francisco (UCSF).
Psychologists have known for decades about the so-called "cocktail party effect," a name that evokes the Mad Men era in which it was coined. It is the remarkable human ability to focus on a single speaker in virtually any environment -- a classroom, sporting event or coffee bar -- even if that person's voice is seemingly drowned out by a jabbering crowd.
To understand how selective hearing works in the brain, UCSF neurosurgeon Edward Chang, MD, a faculty member in the UCSF Department of Neurological Surgery and the Keck Center for Integrative Neuroscience, and UCSF postdoctoral fellow Nima Mesgarani, PhD, worked with three patients who were undergoing brain surgery for severe epilepsy.
Part of this surgery involves pinpointing the parts of the brain responsible for disabling seizures. The UCSF epilepsy team finds those locales by mapping the brain's activity over a week, with a thin sheet of up to 256 electrodes placed under the skull on the brain's outer surface or cortex. These electrodes record activity in the temporal lobe -- home to the auditory cortex.
- Category: Science & Technology