Separate Representation of Stimulus Frequency, Intensity, and Duration in Auditory Sensory Memory: An Event-Related Potential and Dipole-Model Analysis

TLDR

The mismatch negativity (MMN) is thought to reflect change detection by comparing sensory input from a deviant stimulus with the neural representation of repetitive stimuli in echoic memory. The present study examined the neural correlates of acoustic stimulus representation in echoic sensory memory. The authors investigated auditory sensory memory indirectly by recording the MMN, an event‑related potential elicited by changes in a repetitive sound. Scalp topographies of MMNs elicited by frequency, intensity, or duration deviations differed, and dipole‑model analysis supports that these attributes are represented by distinct neural populations in auditory cortex, indicating separate neural representations in echoic memory.

Abstract

Abstract The present study analyzed the neural correlates of acoustic stimulus representation in echoic sensory memory. The neural traces of auditory sensory memory were indirectly studied by using the mismatch negativity (MMN), an event-related potential component elicited by a change in a repetitive sound. The MMN is assumed to reflect change detection in a comparison process between the sensory input from a deviant stimulus and the neural representation of repetitive stimuli in echoic memory. The scalp topographies of the MMNs elicited by pure tones deviating from standard tones by either frequency, intensity, or duration varied according to the type of stimulus deviance, indicating that the MMNs for different attributes originate, at least in part, from distinct neural populations in the auditory cortex. This result was supported by dipole-model analysis. If the MMN generator process occurs where the stimulus information is stored, these findings strongly suggest that the frequency, intensity, and duration of acoustic stimuli have a separate neural representation in sensory memory.