Neural oscillation Puns

Previously THC was shown to disrupt neural oscillations (brainwaves) by causing slow waves measured on EEG in the cat and reducing brain acetylcholine utilization in the hippocampus by way of suppressing the brainstem's ascending reticular activating system (which projects directly to and controls firing rate in the thalamus).

> Δ9-THC Disrupts Gamma (γ)-Band Neural Oscillations in Humans

> August, 2015

> Gamma (γ)-band oscillations play a key role in perception, associative learning, and conscious awareness and have been shown to be disrupted by cannabinoids in animal studies. The goal of this study was to determine whether cannabinoids disrupt γ-oscillations in humans and whether these effects relate to their psychosis-relevant behavioral effects. The acute, dose-related effects of Δ-9-tetrahydrocannabinol (Δ(9)-THC) on the auditory steady-state response (ASSR) were studied in humans (n=20) who completed 3 test days during which they received intravenous Δ(9)-THC (placebo, 0.015, and 0.03 mg/kg) in a double-blind, randomized, crossover, and counterbalanced design. Electroencephalography (EEG) was recorded while subjects listened to auditory click trains presented at 20, 30, and 40 Hz.

> Psychosis-relevant effects were measured with the Positive and Negative Syndrome scale (PANSS). Δ(9)-THC (0.03 mg/kg) reduced intertrial coherence (ITC) in the 40 Hz condition compared with 0.015 mg/kg and placebo. No significant effects were detected for 30 and 20 Hz stimulation. Furthermore, there was a negative correlation between 40 Hz ITC and PANSS subscales and total scores under the influence of Δ(9)-THC.

> Δ(9)-THC (0.03 mg/kg) reduced evoked power during 40 Hz stimulation at a trend level. Recent users of cannabis showed blunted Δ(9)-THC effects on ITC and evoked power. We show for the first time in humans that cannabinoids disrupt γ-band neural oscillations. Furthermore, there is a relationship between disruption of γ-band neural oscillations and psychosis-relevant phenomena induced by cannabinoids. These findings add to a growing literature suggesting some overlap between the acute effects of cannabinoids and the behavioral and psychophysiological alterations observed in psychotic disorders.

> https://pubmed.ncbi.nlm.nih.gov/25709097/

And once again, the same identical effect to the tiniest detail I had immediately from anti-muscarinic receptor blockade I also had from THC (in marijuana) on two separate prior occasions se

I am trying to learn more about memory, especially about memory consolidation.

Is there an easy way to understand how hippocampal neural oscillations of different frequencies help/are involved in memory consolidation?

I'm just a second year Psychology student and most of the articles I found on this subject are quite difficult to understand.

I would really appreciate some help!

I could imagine that C. elegans, with its 302 neurons, may show single-cell microscopic oscillation, but presumably there are not enough neurons to show mesoscopic or macroscopic oscillation?

I'm trying to find out if (EEG?) studies have been done on organisms smaller than mice say, but larger than C. elegans. I'm particularly interested, because if neural oscillation is an evolved feature, perhaps there are some organisms that don't show it, either because they don't need it (too simple) or because they never evolved it (for some trade-off reason perhaps). Is there a critical size of organism where neural oscillation at the various levels becomes useful?

Havin' a hard time over here!