A central question in the study of human behavior is the origin of willed action. EEG recordings of surface brain activity from human subjects performing a self-initiated movement show that the subjective experience of wanting to move follows, rather than precedes, the 'readiness potential'--an electrophysiological mark of motor preparation. This raises the issue of how conscious experience of willed action is generated. Here we show that patients with parietal lesions can report when they started moving, but not when they first became aware of their intention to move. This stands in contrast with the performance of cerebellar patients who behaved as normal subjects. We thus propose that when a movement is planned, activity in the parietal cortex, as part of a cortico-cortical sensorimotor processing loop, generates a predictive internal model of the upcoming movement. This model might form the neural correlate of motor awareness.

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The feeling of being excluded from a social interaction triggers social pain, a sensation as intense as actual physical pain. Little is known about the neurophysiological underpinnings of social pain. We addressed this issue using intracranial electroencephalography in 15 patients performing a ball game where inclusion and exclusion blocks were alternated. Time-frequency analyses showed an increase in power of theta-band oscillations during exclusion in the anterior insula (AI) and posterior insula, the subgenual anterior cingulate cortex (sACC), and the fusiform "face area" (FFA). Interestingly, the AI showed an initial fast response to exclusion but the signal rapidly faded out. Activity in the sACC gradually increased and remained significant thereafter. This suggests that the AI may signal social pain by detecting emotional distress caused by the exclusion, whereas the sACC may be linked to the learning aspects of social pain. Theta activity in the FFA was time-locked to the observation of a player poised to exclude the participant, suggesting that the FFA encodes the social value of faces. Taken together, our findings suggest that theta activity represents the neural signature of social pain. The time course of this signal varies across regions important for processing emotional features linked to social information.

People can be overly optimistic not only about their own future but also for the people with whom they identify. Furthermore, interpersonal perception generally forms along two universal dimensions, i.e. warmth and competence. In this study, we created four fictional characters that would map onto each quadrant of the two-dimensional space of warmth and competence, i.e. one in-group member (high on both warmth and competence) and three out-group members (high warmth, low competence; high competence, low warmth; low on both warmth and competence). We then asked respondents to assess the likelihood of each character experiencing a series of identical desirable and undesirable events in order to uncover potential optimistic biases. Our study had two goals. First, we wanted to balance the target desirable and undesirable events on four key characteristics, i.e. event frequency, controllability, emotional intensity and personal experience with the event. Second, we wanted to investigate whether stereotypes of warmth and competence could influence the respondents’ likelihood estimates for each character. We show that respondents manifested a strong desirability bias, expecting more desirable than undesirable events for the in-group member and the reverse pattern for the extreme out-group member. More important, we show that, within desirable and undesirable events, respondents anchored their judgments for the in-group member on their personal experience with the target events, further revealing an egocentric bias, but turned to stereotypical knowledge in the form of warmth and competence to judge out-group members. Implications for both social perception and optimism research are discussed.

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When a subject is asked to respond as quickly as possible to a stimulus he/she responds much faster if this stimulus is preceded by a warning cue. This cue enables the subject to anticipate the forthcoming stimulus, initiating neural processes subserving the future perception and processing of the target stimulus and the motor preparation of the associated response action. It has recently been suggested that neuronal activity before such an anticipated target stimulus could be associated with modulations in neuronal synchronization and oscillatory activity. Here we recorded electrical brain activity whilst subjects performed a choice reaction time task, in which one of the stimuli could be predicted with 90% certainty. We show that the prediction of a forthcoming stimulus was associated with an increase in gamma oscillations overlying occipital areas and a decrease in beta oscillations overlying sensorimotor cortex before the stimulus was presented. We suggest that these regionally specific modulations in oscillatory activity reflect the establishment of neural networks that are 'primed' for the future processing of the forthcoming predictable visual stimulus.