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Christine Y Ducommun

Publications and source records attributed to Christine Y Ducommun.

2 recordsLinked to original sources

Cortical motion deafness.

The extent to which the auditory system, like the visual system, processes spatial stimulus characteristics such as location and motion in separate specialized neuronal modules or in one homogeneously distributed network is unresolved. Here we present a patient with a selective deficit for the perception and discrimination of auditory motion following resection of the right anterior temporal lobe and the right posterior superior temporal gyrus (STG). Analysis of stimulus identity and location within the auditory scene remained intact. In addition, intracranial auditory evoked potentials, recorded preoperatively, revealed motion-specific responses selectively over the resected right posterior STG, and electrical cortical stimulation of this region was experienced by the patient as incoming moving sounds. Collectively, these data present a patient with cortical motion deafness, providing evidence that cortical processing of auditory motion is performed in a specialized module within the posterior STG.

Acoustic Stimulation↗

Segregated processing of auditory motion and auditory location: an ERP mapping study.

Recent studies have revealed a distinct cortical network activated during the analysis of sounds' spatial properties. Whether common brain regions in this auditory where pathway are involved in both auditory motion and location processing is unresolved. We investigated this question with multichannel auditory evoked potentials (AEPs) in 11 subjects. Stimuli were binaural 500-ms white noise bursts. Interaural time differences (ITD) created the sensation of moving or stationary sounds within each auditory hemifield, and subjects discriminated either their position or direction of motion in a blocked design. Scalp potential distributions (AEP maps) differentiated electric field configurations across stimulus classes. The initial approximately 250-ms poststimulus yielded common topographies for both stimulus classes and hemifields. After approximately 250-ms, moving and stationary sounds engaged distinct cortical networks at two time periods, again with no differences observed between hemifields. The first ( approximately 250- to 350-ms poststimulus onset) was during stimulus presentation, and the second ( approximately 550- to 900-ms poststimulus onset) occurred after stimulus offset. Distributed linear inverse solutions of the maps over the 250- to 350-ms time period revealed not only bilateral inferior frontal activation for both types of auditory spatial processing, but also strong right inferior parietal activation in the case of auditory motion discrimination. During the later 550-to 900-ms time period, right inferior parietal and bilateral inferior frontal activity was again observed for moving sounds, whereas strong bilateral superior frontal activity was seen in the case of stationary sounds. Collectively, the evidence supports the existence of partly segregated networks within the auditory where pathway for auditory location and auditory motion processing.

Acoustic Stimulation↗