Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

Coordinated activity spanning anatomically distributed neuronal networks underpins cognition and mediates limbic-cortical interactions during learning, memory, and decision-making. We used CP55940, a potent agonist of brain cannabinoid receptors known to disrupt coordinated activity in hippocampus, to investigate the roles of network oscillations during hippocampal and medial prefrontal cortical (mPFC) interactions in rats. During quiet wakefulness and rest, CP55940 dose-dependently reduced 0.1-30 Hz local field potential power in CA1 of the hippocampus while concurrently decreasing 30-100 Hz power in mPFC; these contrasting population-level effects were paralleled by differential effects on underlying single-unit activity in the two structures. During decision-making phases of a spatial working memory task, CP5540-induced deficits in hippocampal theta and prefrontal gamma oscillations were observed alongside disrupted theta-frequency coherence between the two structures. These changes in coordinated limbic-cortical network activities correlated with (1) reduced accuracy of task performance, (2) impaired phase-locking of prefrontal single-unit spiking to the local gamma and hippocampal theta rhythms, and (3) impaired task-dependent activity in a subset of mPFC units. In addition to highlighting the importance of CA1-mPFC network oscillations for cognition, these results implicate disrupted theta-frequency coordination of CA1-mPFC activity in the cognitive deficits caused by exogenous activation of brain cannabinoid receptors.

Original publication

DOI

10.1523/JNEUROSCI.2970-11.2011

Type

Journal article

Journal

J Neurosci

Publication Date

26/10/2011

Volume

31

Pages

15560 - 15568

Keywords

Action Potentials, Analysis of Variance, Animals, Biological Clocks, Brain Waves, Cannabinoid Receptor Agonists, Cannabinoid Receptor Antagonists, Confidence Intervals, Cyclohexanols, Dronabinol, Electric Stimulation, Evoked Potentials, Hippocampus, Immunosuppressive Agents, Male, Maze Learning, Memory, Short-Term, Mental Disorders, Nerve Net, Neurons, Prefrontal Cortex, Rats, Rats, Long-Evans, Reaction Time, Receptors, Cannabinoid, Statistics, Nonparametric, Time Factors