Precuneus contributes to attentive control of finger movement.
AIM
To examine whether precuneus subserves the attentive control of finger movement or whether it mediates the movement preparation and motor inhibition.


METHODS
In the Preparation Stage, subjects were shown with a 5-number string in which each number stood for a key-pressing response, the number strings included a complex pattern (eg, 4-1-4-2-3), or a simple one (eg, 2-2-2-2-2), or a null one (ie, x-x-x-x-x). In the Execution Stage, five reaction signs were presented one by one and subjects were required to press the corresponding key to each sign sequentially (eg, in the 4-1-4-2-3 preparation example, subjects press key 4 to the first sign, press key 1 to the second sign, key 4 to the third sign and so on). For the null preparation pattern, five numbers, rather than the reaction signs, were shown at the same pace as in the other two conditions and subjects were to press the corresponding keys.


RESULTS
Left medial frontal gyrus (BA 6) and precentral gyrus (BA 6) were involved in both of the Preparation Stage and the Execution Stage, whereas left precuneus (BA 7) was activated only in the Execution Stage.


CONCLUSION
Precuneus mediates the attentive control of finger movement, but not the movement preparation or motor inhibition.