Epidural cerebellar stimulation drives widespread neural synchrony in the intact and stroke perilesional cortex.
Aamir Abbasi, Nathan P Danielsen, Jennifer Leung and 3 others
PMID 34039346WHAT IT FOUND
In anaesthetised rats, epidural cerebellar stimulation altered firing rates and increased neural synchrony in the motor cortex, both in intact tissue and in a stroke model.
These were immediate electrophysiological changes. No motor function was tested, so this does not demonstrate that the stimulation improves recovery.
Key findings
01Stimulation changed the firing rate of most recorded neurons in the intact motor cortex, with 56% increasing and 20% decreasing their firing.
02Stimulation increased the synchrony of firing between pairs of neurons in the intact motor cortex, and this effect was independent of whether individual neurons increased or decreased their firing rate.
03In the acute stroke model, stimulation similarly altered firing rates in the tissue surrounding the lesion and increased neural synchrony after stimulation ended.
STILL TO COME
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study was performed in anaesthetised rats, not awake animals or humans. The anaesthetic itself creates specific brain wave patterns that may influence the results. The stroke model was acute (induced immediately before recording), which does not reflect the chronic stroke state seen in most clinical rehabilitation patients. The study measured only electrical activity in the brain. It did not assess motor behaviour or physical function, so it provides no evidence that these neural changes lead to clinical improvement. The sample size was very small (8 rats total, 4 per group). The stimulation was epidural (on the surface of the brain), which is far more invasive than the transcranial methods currently used in human research.
Declared interests
Funding was provided by Cedars-Sinai Medical Center, the National Institutes of Health, and the National Science Foundation. No specific conflicts of interest were declared in the provided text.
The easy way to misread this
Do not interpret these neural changes as evidence that cerebellar stimulation improves motor function or recovery in stroke patients. The study measured electrical activity in anaesthetised rats with acute brain lesions and did not test any physical movement or clinical outcome.