The broad, long-term objectives of our research are to: 1) determine how the central nervous system (CNS) controls visually-guided limb movements by identifying neural activity related to the behavioral processes and variables that underlie such movements, and 2) characterize the specialized functional roles of different cortical motor areas in the control of movement. The current proposal is based upon the results of single cell recording studies which found evidence that several different types of neural activity related to the early stages of vasomotor processing are located in the cortical motor areas of monkeys performing visually-guided tracking tasks. These include activity related independently to: 1) which visual target is captured, 2) the direction of Specific Aim 1: To test the hypothesis that there is a differential distribution of target-independent activity in the four premotor areas. The results of this study will provide new information about the extent to which these four premotor areas participate in early stages of vasomotor transformations.
Specific Aim 2 : To test the hypothesis that target-dependent activity is a neural correlate of visually guided-limb movements. An oculomotor delayed response task will be used to verify that target-dependent activity is contingent upon the execution of limb and/or cursor movements. This task will provide convincing evidence that the previously observed target-dependent activity is indeed related to high-level aspects of vasomotor transformations.
Specific Aim 3 : To test the hypothesis that there are neurons in these four premotor areas whose activity is related independently to 1) the target captured by the cursor, 2) the director of cursor movement, or 3) the endpoint of hand/joystick movement. Since the equilibrium point hypothesis and analytical models of motor processing would make different predictions regarding the occurrence of these different patterns of activity, the results of these studies will provide evidence regarding the plausibility of these two models of vasomotor processing.
| Crutcher, M D; Russo, G S; Ye, S et al. (2004) Target-, limb-, and context-dependent neural activity in the cingulate and supplementary motor areas of the monkey. Exp Brain Res 158:278-88 |
