Adaptation to novel visuomotor transformations for example when navigating a cursor on a computer monitor by using a computer mouse, can be explicit or implicit. Explicit adjustments are made when people are informed about the occurrence and the type of a novel visuomotor transformation and intentionally modify their movements. Implicit adjustments, in contrast, are made without reportable knowledge of a novel visuomotor transformation and without a change intention. The relation of implicit adjustments to explicit adjustments needs further clarification. Here we (...) show that these two types of adjustment occur at the same time and remain functionally independent. The size of total adjustment turned out to be the sum of explicit and implicit adjustments measured in isolation, even when both processes produce opposite outcomes. In perspective our results demonstrate that automatic, implicit processes of motor control are not superseded by intentional, explicit ones, but only superposed. (shrink)

Fronto-parietal activity has been frequently observed in fMRI and PET studies of attention, working memory, and episodic memory retrieval. Several recent fMRI studies have also reported fronto-parietal activity during conscious visual perception. A major goal of this review was to assess the degree of anatomical overlap among activation patterns associated with these four functions. A second goal was to shed light on the possible cognitive relationship of processes that relate to common brain activity across functions. For all reviewed functions we (...) observed a consistent and overlapping pattern of brain activity. The overlap was most pronounced for the bilateral parietal cortex , and dorsolateral prefrontal cortex . The common fronto-parietal activity will be discussed in terms of processes related to integration of distributed representations in the brain. (shrink)

This paper investigated how implicit and explicit knowledge is reflected in event-related potentials in sequence learning. ERPs were recorded during a serial reaction time task. The results showed that there were greater RT benefits for standard compared with deviant stimuli later than early on, indicating sequence learning. After training, more standard triplets were generated under inclusion than exclusion tests and more standard triplets under exclusion than chance level, indicating that participants acquired both explicit and implicit knowledge. However, deviant targets elicited (...) enhanced N2 and P3 components for targets with explicit knowledge but a larger N2 effect for targets with implicit knowledge, revealing that implicit knowledge expresses itself in relatively early components and explicit knowledge in additional P3 components. The results help resolve current debate about the neural substrates supporting implicit and explicit learning. (shrink)