Book Description

Previous investigations have demonstrated that shifting attention across modalities produces changes in neural responding to auditory stimuli at the level of the cortex. More recent studies have presented evidence that alterations in the focus of attention produce opposite changes in responding in the auditory periphery. Few studies, however, have examined the influence of attention on neural signaling at the level of the brainstem. The present study sought to compare the changes in the neural representation of an auditory stimulus at the level of the brainstem across two balanced attending conditions: one engaging visual attention and the other engaging auditory attention. Brainstem auditory evoked potentials (BAEPs) were measured while the participants counted short, infrequent oddball click trains (auditory attending) and while counting targeted instances of Gabor gradient phase shifts (visual attending). BAEPs were employed because they allow the observation of neural responding to auditory stimuli specifically at the level of the brainstem, a region which has seen little investigation in the realm of attention. Our results suggest that across attending conditions, absolute and peak-to-peak amplitudes were significantly different in early and late portions of the waveform.