@article {Johnston2703-18, author = {Kevin Johnston and Liya Ma and Lauren Schaeffer and Stefan Everling}, title = {Alpha-oscillations modulate preparatory activity in marmoset area 8Ad}, elocation-id = {2703-18}, year = {2019}, doi = {10.1523/JNEUROSCI.2703-18.2019}, publisher = {Society for Neuroscience}, abstract = {Cognitive control often requires suppression of prepotent stimulus-driven responses in favour of less potent alternatives. Suppression of prepotent saccades has been shown to require proactive inhibition in the frontoparietal saccade network. Electrophysiological evidence in macaque monkeys has revealed neural correlates of such inhibition in this network, however the interlaminar instantiation of inhibitory processes remains poorly understood as these areas lie deep within sulci in macaques, rendering them inaccessible to laminar recordings. Here we addressed this gap by exploiting the mostly lissencephalic cortex of the common marmoset (Callithrix jacchus). We inserted linear electrode arrays into areas 8Ad {\textemdash} the putative marmoset frontal eye field - and lateral intraparietal area (LIP) of two male marmosets, and recorded neural activity during performance of a task comprised of alternating blocks of trials requiring a saccade either toward a large, high-luminance stimulus or the inhibition of this prepotent response in favour of a saccade toward a small, low-luminance stimulus. We observed prominent task-dependent activity in both alpha/gamma bands of the local field potential and discharge rates of single neurons in area 8Ad during a prestimulus task epoch in which the animals had been instructed which of these two tasks to perform but prior to peripheral stimulus onset. These data are consistent with a model in which rhythmic alpha-band activity in deeper layers inhibits spiking in upper layers to support proactive inhibitory saccade control.SIGNIFICANCE STATEMENTFailures to inhibit automatic saccadic responses are a hallmark of many neuropsychiatric disorders. How this process is implemented across the cortical layers in the frontoparietal saccade network remains unknown, as many of the areas are inaccessible to laminar recordings in macaques. Here we investigated laminar neural activity in marmoset monkeys which have a smooth cortex. Monkeys were required either to generate or inhibit a prepotent saccade response. In area 8Ad, the putative frontal eye field in marmosets, rhythmic alpha-band activity (9-14 Hz) was higher in deeper layers and spiking activity was lower in upper layers when the animals were instructed to suppress a saccade towards a peripheral stimulus. Reduced alpha power during task preparation may be the underlying common neural basis of a saccade suppression deficit.}, issn = {0270-6474}, URL = {https://www.jneurosci.org/content/early/2019/01/15/JNEUROSCI.2703-18.2019}, eprint = {https://www.jneurosci.org/content/early/2019/01/15/JNEUROSCI.2703-18.2019.full.pdf}, journal = {Journal of Neuroscience} }