Examining cross-modal influence of the auditory brainstem response
W. David Hairston, Tomasz R Letowski, Kaleb McDowell
Poster
Time: 2009-06-30 09:00 AM – 10:30 AM
Last modified: 2009-06-04
Abstract
While sensory systems have classically been defined and studied in isolation of one another, interactions have been shown at both the cortical and sub-cortical levels, with some studies showing visual influence even in brainstem level auditory structures (Musacchia, Sams et al. 2006). Recent evidence for enhanced auditory brainstem response when paired with concurrent visual stimulation is particularly intriguing, especially considering other work suggesting attention-related mediation of the frequency-following response (FFR) component (Galbraith, Olfman et al. 2003). Here, we extend this work to explore the possibility of attention-mediated suppression of the brainstem FFR, analogous to what has been shown cortically (“cross-modal deactivation�, e.g. (Hairston, Hodges et al. 2008). Additionally, we seek to further explore the connection between brainstem- and cortical-level attenuation within the same paradigm.
Subjects (currently recruiting) perform fairly difficult visual and auditory duration-discrimination tasks within separate blocks. Stimuli are adjusted according to each subject’s perceptual threshold, acquired during prior testing to ensure equivalent difficulty and sufficient attention to the target modality. Background non-task relevant tones (220Hz) are used to elicit the brainstem 220Hz FFR, with occasional oddball stimuli (259Hz) providing a cortical mismatch-negativity response. Fourier power for the principle background (220Hz) frequency is compared for each modality above resting (no-task baseline). We anticipate not only enhanced power during auditory tasks, but an attenuated signal when attention in focused on vision, suggesting that cross-modal inhibition can affect processing almost immediately after reception.
References:
Musacchia, G., M. Sams, et al. (2006). "Seeing speech affects acoustic information processing in the human brainstem." Exp Brain Res 168(1-2): 1-10.
Galbraith, G. C., D. M. Olfman, et al. (2003). "Selective attention affects human brain stem frequency-following response." Neuroreport 14(5): 735-8.
Hairston, W. D., D. A. Hodges, et al. (2008). "Closing the mind's eye: deactivation of visual cortex related to auditory task difficulty." Neuroreport 19(2): 151-154.
Subjects (currently recruiting) perform fairly difficult visual and auditory duration-discrimination tasks within separate blocks. Stimuli are adjusted according to each subject’s perceptual threshold, acquired during prior testing to ensure equivalent difficulty and sufficient attention to the target modality. Background non-task relevant tones (220Hz) are used to elicit the brainstem 220Hz FFR, with occasional oddball stimuli (259Hz) providing a cortical mismatch-negativity response. Fourier power for the principle background (220Hz) frequency is compared for each modality above resting (no-task baseline). We anticipate not only enhanced power during auditory tasks, but an attenuated signal when attention in focused on vision, suggesting that cross-modal inhibition can affect processing almost immediately after reception.
References:
Musacchia, G., M. Sams, et al. (2006). "Seeing speech affects acoustic information processing in the human brainstem." Exp Brain Res 168(1-2): 1-10.
Galbraith, G. C., D. M. Olfman, et al. (2003). "Selective attention affects human brain stem frequency-following response." Neuroreport 14(5): 735-8.
Hairston, W. D., D. A. Hodges, et al. (2008). "Closing the mind's eye: deactivation of visual cortex related to auditory task difficulty." Neuroreport 19(2): 151-154.