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When we look at our hands, we immediately know that they are part of our own body. This feeling of ownership of our limbs is a fundamental aspect of self-consciousness. We have studied the neuronal counterparts of this experience. A perceptual illusion was used to manipulate feelings of ownership of a rubber hand presented in front of healthy subjects while(More)
When task instructions are given, the human brain establishes a task set before the task is actually performed. By introducing a delay between the instruction and the task, we have identified the neural correlates of task sets using functional magnetic resonance imaging (fMRI). Subjects were instructed to remember a sequence of positions or letters, either(More)
When we observe someone performing an action, do our brains simulate making that action? Acquired motor skills offer a unique way to test this question, since people differ widely in the actions they have learned to perform. We used functional magnetic resonance imaging to study differences in brain activity between watching an action that one has learned(More)
In the "rubber-hand illusion," the sight of brushing of a rubber hand at the same time as brushing of the person's own hidden hand is sufficient to produce a feeling of ownership of the fake hand. We shown previously that this illusion is associated with activity in the multisensory areas, most notably the ventral premotor cortex (Ehrsson et al., 2004).(More)
It is controversial whether the dorsolateral prefrontal cortex is involved in the maintenance of items in working memory or in the selection of responses. We used event-related functional magnetic resonance imaging to study the performance of a spatial working memory task by humans. We distinguished the maintenance of spatial items from the selection of an(More)
We have used positron emission tomography to study the functional anatomy of motor sequence learning. Subjects learned sequences of keypresses by trial and error using auditory feedback. They were scanned with eyes closed under three conditions: at rest, while performing a sequence that was practiced before scanning until overlearned, and while learning new(More)
We used positron emission tomography to study new learning and automatic performance in normal volunteers. Subjects learned sequences of eight finger movements by trial and error. In a previous experiment we showed that the prefrontal cortex was activated during new learning but not during during automatic performance. The aim of the present experiment was(More)
Event-related potential studies in man suggest a role for the supplementary motor area (SMA) in movement preparation, particularly when movements are internally generated. In a previous study combining PET with recording of movement-related cortical potentials, we found similar SMA activation and early pre-movement negativity during self-initiated and(More)
Despite the intuition that we can shift cognitive set on instruction, some behavioral studies have suggested that set shifting might only be accomplished once we engage in performance of the new task. It is possible that set switching consists of more than one component cognitive process and that the component processes might segregated in time. We recorded(More)
1. Differences in the distribution of relative regional cerebral blood flow during motor imagery and execution of a joy-stick movement were investigated in six healthy volunteers with the use of positron emission tomography (PET). Both tasks were compared with a common baseline condition, motor preparation, and with each other. Data were analyzed for(More)