Our brains have an “auto-correct” feature that we deploy when re-interpreting ambiguous sounds, a team of scientists has discovered. Its findings, which appear in the Journal of Neuroscience, point to new ways we use information and context to aid in speech comprehension.

“What a person thinks they hear does not always match the actual signals that reach the ear,” explains Laura Gwilliams, a doctoral candidate in NYU’s Department of Psychology, a researcher at the Neuroscience of Language Lab at NYU Abu Dhabi, and the paper’s lead author. “This is because, our results suggest, the brain re-evaluates the interpretation of a speech sound at the moment that each subsequent speech sound is heard in order to update interpretations as necessary.

“Remarkably, our hearing can be affected by context occurring up to one second later, without the listener ever being aware of this altered perception.”

“For example, an ambiguous initial sound, such as ‘b’ and ‘p,’ is heard one way or another depending on if it occurs in the word ‘parakeet’ or ‘barricade,’ ” adds Alec Marantz, principal investigator of the project, a professor in NYU’s departments of Linguistics and Psychology, and co-director of NYU Abu Dhabi’s Neuroscience of Language Lab, where the research was conducted. “This happens without conscious awareness of the ambiguity, even though the disambiguating information doesn’t come until the middle of the third syllable.”

The researchers have created examples of these stimuli.