“How”: The connection between acoustics and perception

Speech is both the most important and the most frequent sound that we hear. We have so much experience perceiving speech that it often seems relatively effortless. However, when one examines the speech signal a bit more closely, several severe challenges are evident such as considerable acoustic complexity and extreme acoustic variability across sounds, utterances, talkers, and environments. Given these challenges, how does speech perception work? In this talk, we will consider how speech sounds are produced and observe some of their prevailing acoustic characteristics in American English. We will then embark on a brief tour of the auditory system. We will see how speech sounds are transduced into action potentials in the cochlea and then how the neural representation of speech evolves as one travels up the central auditory system toward the brain. This tour will conclude with the discussion of speech processing in the brain, including cortical pathways for processing different aspects of the speech signal. Understanding speech acoustics and processing can directly inform efforts to provide speech privacy.