Comparing the dynamics of ongoing activity in awake and anesthetized monkey

Previous studies using Voltage sensitive dyes imaging on anesthetized cats reported that spontaneous ongoing cortical activity in the primary visual cortex represents dynamic spatial patterns many of which resembling the functional architecture of Orientation domains, and span large cortical areas (Grinvald et al., 1989; Arieli et al., 1995; Arieli et al., 1996; Tsodyks et al., 1999; Kenet et al., 2003; Fox et al., 2006; Fox et al., 2007b). Those results suggest that ongoing activity may play an important role in cortical processing and challenge the classical notion which considers spontaneous ongoing cortical activity as noise (Ferster D., 1996; Ringach D. L., 2003; Fox et al., 2007a).We preformed VSDI of ongoing cortical activity in the visual cortices of awake and anesthetized monkeys. Our results shows that in the anesthetized monkey spontaneous cortical activity shows larger repertoire of cortical states which resemble both Ocular Dominance domains as well as Orientation domains. We found large bias toward the representation of cortical states which resemble ocular dominance domains rather than orientation domains. In comparison to the spontaneous ongoing activity in the anesthetized monkey the dynamics of ongoing activity in the awake monkey is much faster, and the coherence-length is much smaller