Parallel EEG assessment of different sound predictability levels in tinnitus
ObjectiveTinnitus denotes perception of a non-environmental sound and might result from aberrant auditory prediction. Successful prediction of formal (e.g. type) and temporal sound characteristics facilitates the filtering of irrelevant information ("sensory gating", SG). Here, we explored if and how parallel manipulations of formal and temporal predictability affect sensory gating in persons with and without tinnitus. MethodsAge-, education- and sex-matched persons with and without tinnitus (N = 52) participated and listened to paired-tone "oddball" sequences, varying in formal (standard vs. deviant pitch) and temporal predictability (isochronous vs. random timing). EEG was recorded from 128 channels and data were analyzed by means of temporal spatial principal component analysis (tsPCA). ResultsSG was observed in P50- and N100-like activity (amplitude suppression for the 2nd tone in the pair) in both timing conditions and groups. Correspondingly, deviants elicited overall larger amplitudes than standards. However, only in persons without tinnitus N100-like activity in response to deviants was enhanced with isochronous relative to random timing. ConclusionsPersons with tinnitus do not benefit similarly as persons without tinnitus from temporally predictable context in deviance processing. SignificanceThe current results indicate altered temporal sensitivity and selective attention allocation in persons with tinnitus. Highlights- Persons with tinnitus display altered auditory predictions affecting the processing of unexpected auditory input - Position predictions did not differ between persons with tinnitus and without - Temporal predictability facilitated deviance processing for P50-like activity in persons with tinnitus and without