Spontaneous high-gamma band activity reflects functional organization of auditory cortex in the awake macaque.
In the absence of sensory stimuli, spontaneous activity in the brain has been shown to exhibit organization at multiple spatiotemporal scales. In the macaque auditory cortex, responses to acoustic stimuli are tonotopically organized within multiple, adjacent frequency maps aligned in a caudorostral direction on the supratemporal plane (STP) of the lateral sulcus. Here, we used chronic microelectrocorticography to investigate the correspondence between sensory maps and spontaneous neural fluctuations in the auditory cortex. We first mapped tonotopic organization across 96 electrodes spanning approximately two centimeters along the primary and higher auditory cortex. In separate sessions, we then observed that spontaneous activity at the same sites exhibited spatial covariation that reflected the tonotopic map of the STP. This observation demonstrates a close relationship between functional organization and spontaneous neural activity in the sensory cortex of the awake monkey.
National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA. makoto_fukushima@me.com
Makoto
M
Fukushima
Richard C
RC
Saunders
David A
DA
Leopold
Mortimer
M
Mishkin
Bruno B
BB
Averbeck
D000161:Acoustic Stimulation; D000704:Analysis of Variance; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001931:Brain Mapping; D058256:Brain Waves / Q000502:physiology*; D004569:Electroencephalography; D008253:Macaca mulatta; D013223:Statistics as Topic; D014851:Wakefulness / Q000502:physiology*