CNS activity changes in similar tasks
Grip style appeared to change CNS activity in this study. So, when interpreting this, we know CNS controls movement and that changes in CNS are associated with movement disorders. But my interpretation is that this really highlights that specific movements are associated with specific areas of the CNS. Hence as clinicians we may see loss of specific movement function in response to loss of CNS function in very localised areas of the brain. Enjoy the read!
Cortical Activity in Precision- Versus Power-Grip Tasks: An fMRI Study
Ehrsson, H et al, 2000
Functional magnetic resonance imaging was used to compare human brain activity during force production by the right hand when subjects used a precision grip and a power grip. The activity recorded in the primary sensory and motor cortex contralateral to the operating hand was higher when the power grip was applied than when subjects applied force with a precision grip. In contrast, the activity in the ipsilateral ventral premotor area, the rostral cingulate motor area, and at several locations in the posterior parietal and prefrontal cortices was stronger while making the precision grip than during the power grip. The power grip was associated predominately with contralateral left-sided activity, whereas the precision-grip task involved extensive activations in both hemispheres. Thus the findings indicate that in addition to the primary motor cortex, premotor and parietal areas are important for control of fingertip forces during precision grip. Moreover, the ipsilateral hemisphere appears to be strongly engaged in the control of precision-grip tasks performed with the right hand.