Bridging the chasm: Animal physiology and human psychophysics

Abstract

A goal of animal auditory neuroscience is to understand how humans process and perceive sound. Encouragingly, hypotheses about brain function, generated from psychoacoustics, are sometimes confirmed by physiological experiments. A notable example is the Jeffress model of processing of interaural time differences. This has been largely supported by physiology and indeed we showed that neural activity in the midbrain and cortex, in response to Binaural Masking Level Difference stimuli, was entirely consistent with this cross-correlation model of binaural processing. However, such comparisons of physiology and psychophysics are often beset by caveats of species and anesthesia. This is one reason why the sharpness of human frequency tuning is still currently debated. In recent experiments, we have measured tuning behaviorally and by direct and indirect physiological methods, all in the same species. These different measures are in good agreement, supporting the notion that the cochlea determines perceptual fr...