PMID-17057705 Long-term motor cortex plasticity induced by an electronic neural implant.
- used an implanted neurochip.
- record from site A in motor cortex (encodes movement A)
- stimulate site B of motor cortex (encodes movement B)
- after a few days of learning, stimulate A and generate mixure of AB then B-type movements.
- changes only occurred when stimuli were delivered within 50ms of recorded spikes.
- quantified with measurement of (to) radial/ulnar deviation and flexion/extension of the wrist.
- stimulation in target (site B) was completely sub-threshold (40ua)
- distance between recording and stimulation site did not matter.
- they claim this is from Hebb's rule: if one neuron fires just before another (e.g. it contributes to the second's firing), then the connection between the two is strengthened. However, i originally thought this was because site A was controlling the betz cells in B, therefore for consistency A's map was modified to agree with its /function/.
- repetitive high-frequency stimulation has been shown to expand movement representations in the motor cortex of rats (hmm.. interesting)
- motor cortex is highly active in REM
____References____
|