Electrophysiological correlates of impaired response inhibition during inhalation of propionic acid.

Chemosensory stimulation can impair cognitive processing, which we demonstrated previously in human volunteers who showed reduced behavioral accuracy in a go/nogo flanker task during 4-hr, whole-body exposure to 10 ppm propionic acid but not during 0.3 or 5 ppm exposures (Hey et al., 2009). Now we investigated event-related potentials (ERP) in a subgroup of six male volunteers from the same study to identify which cognitive processes were sensitive to propionic acid exposure. The ERP subgroup showed the same increases in chemosensory perceptions and error rate during 10 ppm exposure as the whole group. In addition several exposure-related effects were seen in the ERPs: first there were effects of the absolute level of exposure on ERP components related to inhibition (nogo-P3) and conscious error perception (late PE). We assume that the unpleasant smell of propionic acid mediates these effects. Second, there were effects related to the variability of exposure on components related to processing in conflict and error trials (N2 and error-P3). We assume that exposure variability disturbs processing especially in critical task situations such as conflict and errors. From our results we conclude that ERPs are a valuable tool to examine chemosensory mediated impairment on different cognitive processing states and their neural substrates. (PsycINFO Database Record (c) 2013 APA, all rights reserved)
Source: Journal of Psychophysiology - Category: Psychiatry & Psychology Authors: Source Type: research