The sensory thalamus and cerebral motor cortex are affected concurrently during induction of anesthesia with propofol: a case series with intracranial electroencephalogram recordings

Abstract

We conclude that induction of anesthesia with propofol in these patients was associated with concurrent alterations of cortical and sensory thalamic activity.

Motor System Interactions in the Beta Band Decrease during Loss of Consciousness

“…The propofol induced reduction in cortical broadband activity that we observed was weak, but is in general agreement with previous human studies examining ECoG during anesthesia induction (Breshears et al, 2010, Verdonck et al, 2014). The subcortical broadband gamma reduction confirms similar findings in rodent studies (Reed et al, 2013), and in one small series of thalamic recordings in humans (Verdonck et al, 2014).…”

“…The subcortical broadband gamma reduction confirms similar findings in rodent studies (Reed et al, 2013), and in one small series of thalamic recordings in humans (Verdonck et al, 2014). Broadband gamma power in cortex is thought to be an index of local neural activity and a surrogate for neural spiking (Miller et al, 2007, Manning et al, 2009).…”

“…In some cases, this emerging low frequency activity is asynchronous across cortex and has been interpreted as a mechanism whereby different brain networks become disconnected from one another (Lewis et al, 2012, Purdon et al, 2013). In many of these studies, the low frequency activity is in a slightly lower frequency range (<2 Hz) than is observed here, nevertheless, other studies have shown these changes over a broader frequency range (Verdonck et al, 2014), and so it is possible that a similar mechanism is involved.…”

“…However the decrease in high frequency power in the cortex was not significant when correcting for multiple comparisons ( Figure 4 ). While the cortical high frequency effect was weak, previous ECoG work has shown similar cortical changes in these frequency ranges during propofol induction (Breshears et al, 2010, Verdonck et al, 2014). Thus, while our result was not statistically robust, it trends in the direction reported by others.…”

“…Several studies have reported low frequency power increases in cortex during anesthesia induction (Breshears et al, 2010, Lewis et al, 2012, Purdon et al, 2013, Verdonck et al, 2014). In some cases, this emerging low frequency activity is asynchronous across cortex and has been interpreted as a mechanism whereby different brain networks become disconnected from one another (Lewis et al, 2012, Purdon et al, 2013).…”