This investigation will utilize in vivo recordings in awake and behaving monkeys to address important questions regarding the role of the posterior parietal cortex in the decision to make movements to visual stimuli. A recent investigation has demonstrated that some cells in this brain area are active when a goal directed eye movement is being planned to a visual stimulus, while other cells are active when a goal directed hand movement is being planned (Synder et al., 1997). This suggests that parietal cortex is actively involved in the decision to make one type of movement or another. However, in this previous study, the decision of movement type and movement location (what to do and where to do it) were made simultaneously, precluding separate analyses of the effect of these two different decisions on cell activity. In the current experiment, by separating these two decisions, it will be possible to determine if the activity of the posterior parietal cortex reflects the intention to make a particular type of movement before the spatial goal of that movement is available. The answer to this question will have important implications for the role of the posterior parietal cortex in decision making and for the process by which decisions are implemented in the brain.
Calton, Jeffrey L; Dickinson, Anthony R; Snyder, Lawrence H (2002) Non-spatial, motor-specific activation in posterior parietal cortex. Nat Neurosci 5:580-8 |