Analysis of beta bursts activity along the primary motor cortex depth in a rodent model of Parkinson?s disease

MARIO GUSTAVO MURER; DANIELA PIÑA NOVO; MARIANO ANDRÉS BELLUSCIO

Virtual

Congreso; XXXV Congress of Argentine Society for Research in Neurosciences; 2020

Argentine Society for Research in Neurosciences

The nigrostriatal degeneration developed during Parkinson´s disease leads to changes in the oscillatory activity both of the basal ganglia and the motor cortex (MC). In particular, exaggerated beta bursts (15?35 Hz) have been shown to emerge after dopamine depletion. This pathological beta band exacerbation is also correlated with motor symptoms of the disease, such as bradykinesia and rigidity. Thus, along with the symptomatic relief resulting from the administration of L-DOPA, which is the gold standard medication, there is a decrease in the prevalence of beta activity. Our previous characterization of beta bursts in MC of hemiparkinsonian mice disclosed a similar pattern, with an increase in their amplitude, duration and occurrence. Interestingly this pattern reversed during the acute effect of L-DOPA, but reappeared when L-DOPA effects have worn off. Here we evaluated the relationship of beta bursts occurrence and their amplitude with the depth within MC. Additionally, we performed the same analysis but separating in rest and movement periods. We found that in lesioned animals, whether they had not received L-DOPA or were out of its acute effect, the number of beta bursts differed significantly along cortical depth. Particularly, there was an increase around layer 5. Beta burst amplitude profile exhibited a small increment around this depth but it didn´t differ significantly.