The Banana Peel Project

The basal ganglia and the cerebellum interact with the cortex through a series of feedback circuits.  The basal ganglia, a group of midbrain nuclei, are involved mainly with the initiation and execution of a movement, whereas the cerebellum tends to modulate ongoing movement. […] The most relevant disorders are the dyskinesias, or abnormal movements.  Basal ganglia degeneration results in movement disorders such as Parkinson’s disease (selective destruction of dopamine-containing neurons) and Huntington’s disease (selective destruction of GABA interneurons).  Parkinson’s disease is classically associated with the triad of resting tremors, muscle rigidity (cogwheel-like), and slowness of movement (bradykinesia, with a festinating gait).  Huntington’s dyskinesias tend to be the opposite of Parkinson’s, with excessive initiation of unwanted movements. […] CB1 receptors are highly expressed in the basal ganglia and the cerebellum.  To understand the possible effect of THC binding to these receptors, some well-established neuronal connections between these structures are relevant to review prior to correlation with CB1 receptor distribution.

-Raymond, L. & Walls, H.C. (2006). “Pharmacology of Cannabinoids” in M. ElSohly (ed) Marijuana and the Cannabinoids. Totowa, NJ: Humana Press.

Animals after the administration of cannabis by the mouth show symptoms in from three quarters of an hour to an hour and a half. In the preliminary stage cats appear uneasy, they exhibit a liking for the dark, and occasionally utter high pitched cries. Dogs are less easily influenced and the preliminary condition here is one of excitement, the animal rushing wildly about and barking vigorously. This stage passes insidiously to the second, that of intoxication. […] In cats the disposition is generally changed showing itself by the animals no longer demonstrating their antipathy to dogs as in the normal condition, but by rubbing up against them while constantly purring; similarly a dog which was inclined to be evil-tempered and savage in its normal condition, when under the influence of hemp became docile and affectionate. […] When standing they hold their legs widely apart and show a particular to and fro swaying movement quite characteristic of the condition. The gait is exceedingly awkward, the animal rolling from side to side, lifting its legs unnecessarily high in its attempts to walk, and occasionally falling. […] Animals generally become more and more listless and drowsy, losing the particular startlings so characteristic in the earlier stage, and eventually sleep three or four hours, after which they may be in quite a normal condition.

 -Dixon, W.E. (1899). “The Pharmacology of Cannabis Indica” in The British Medical Journal, Volume 2, Number 2028, pp. 1354-1357.