Back

The most prominent electrophysiological effect of ketamine is not sufficient to cause anesthesia

Acland, B. T.; Palanca, B. J. A.; Bijsterbosch, J. D.; Snyder, L. H.

2023-09-27 neuroscience
10.1101/2023.09.26.559594 bioRxiv
Show abstract

Electrophysiological recordings during ketamine anesthesia have revealed a slow alternating pattern of high- and low- frequency activity (a "gamma-burst" pattern) that develops with the onset of general anesthesia. We examine the role of NMDA receptor antagonism in generating the gamma-burst pattern and the link between gamma-bursts and dissociative anesthesia. We compare the effects of ketamine with those of the highly selective NMDA receptor antagonist CGS 19755 on multi-site intracranial electrophysiology and behavior in rhesus macaques. Remarkably, we find that animals given a moderate dose of CGS 19755 are able to perform a difficult memory task, while at the same time showing electrophysiological activity similar to ketamine anesthesia, with one key difference: a lack of delta-band LFP modulation. This difference demonstrates that ketamines ability to drive strong delta-band oscillations relies on additional mechanisms beyond NMDA receptor antagonism alone, and points to a key role for the activity underlying delta-band oscillations in causing anesthesia.

Matching journals

The top 5 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.