Separate neural processing of timbre dimensions in auditory sensory memory

& Timbre is a multidimensional perceptual attribute of com-plex tones that characterizes the identity of a sound source. Our study explores the representation in auditory sensory memory of three timbre dimensions (acoustically related to attack time, spectral centroid, and spectrum fine structure), using the mismatch negativity (MMN) component of the audi-tory event-related potential. MMN is elicited by a discriminable change in a sound sequence and ref lects the detection of the discrepancy between the current stimulus and traces in auditory sensory memory. The stimuli used in the present study were carefully controlled synthetic tones. MMNs were re-corded after changes along each of the three timbre dimen-sions and their combinations. Additivity of unidimensional MMNs and dipole modeling results suggest partially separate MMN generators for different timbre dimensions, ref lecting their mainly separate processing in auditory sensory memory. The results expand to timbre dimensions a property of sep-aration of the representation in sensory memory that has already been reported between basic perceptual attributes (pitch, loudness, duration, and location) of sound sources. &amp