Chunk #42 — 4 Discussion — 4.2 EEG discriminating components during the P3 and around reaction time reveal a period of transition from externally driven task-related to internally-driven processing
The precuneus has been associated with a variety of task-relevant cognitive processes, including attentional orienting, visuo-spatial imagery, coordination of motor behavior, success monitoring, and self-referential thoughts (Cavanna and Trimble, 2006; Taylor et al., 2009).Eichele et al. (2005) found precuneus activations correlated with earlier P2 amplitude modulations, though their study used an auditory task. Our reaction-time precuneus activation supports the idea of a transition from the exogenous attentional state required for the visual perceptual decision to motor coordination required for the button press, followed by a reflection on task performance. Activations associated with other forms of internal thought, including posterior cingulate and SFG, were detected both in middle and late windows, and these are discussed in section 4.3.
