RT Journal Article
SR Electronic
T1 Influence of Core Auditory Cortical Areas on Acoustically Evoked Activity in Contralateral Primary Auditory Cortex
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 776
OP 789
DO 10.1523/JNEUROSCI.1784-12.2013
VO 33
IS 2
A1 Andres Carrasco
A1 Trecia A. Brown
A1 Melanie A. Kok
A1 Nicole Chabot
A1 Andrej Kral
A1 Stephen G. Lomber
YR 2013
UL http://www.jneurosci.org/content/33/2/776.abstract
AB In contrast to numerous studies of transcallosal communication in visual and somatosensory cortices, the functional properties of interhemispheric connections between auditory cortical fields have not been widely scrutinized. Therefore, the purpose of the present investigation was to measure the magnitude and type (inhibitory/excitatory) of modulatory properties of core auditory fields on contralateral primary auditory cortex (A1) activity. We combined single-unit neuronal recordings with reversible cooling deactivation techniques to measure variations in contralateral A1 response levels during A1, anterior auditory field (AAF), or simultaneous A1 and AAF neuronal discharge suppression epochs in cat auditory cortex. Cortical activity was evoked by presentation of pure tones, noise bursts, and frequency-modulated (FM) sweeps before, during, and after cortical deactivation periods. Comparisons of neuronal response changes before and during neuronal silencing revealed three major findings. First, deactivation of A1 and AAF-induced significant peak response reductions in contralateral A1 activity during simple (tonal) and complex (noise bursts and FM sweeps) acoustic exposure. Second, decreases in A1 neuronal activity appear to be in agreement with anatomical laminar termination patterns emanating from contralateral auditory cortex fields. Third, modulatory properties of core auditory areas lack hemispheric lateralization. These findings demonstrate that during periods of acoustic exposure, callosal projections emanating from core auditory areas modulate A1 neuronal activity via excitatory inputs.