What is the relationship between action and emotion? People tend to perform approach actions with their dominant hand and avoidance actions with their nondominant hand. In righthanders, the left frontal lobe (which controls the dominant hand) is specialized for approach-motivational states, and the right frontal lobe (which controls the nondominant hand) for avoidance-motivational states. Are brain areas that support affective motivation functionally related to areas that support approach- and avoidance-related motor actions? If so, hemispheric specialization for motivation should covary with hemispheric specialization for motor control. Here we tested this prediction, using electroencephalography (EEG) to compare resting alpha-band power in right- and left-handers. Hemispheric asymmetries in alpha-power, which indexes neural activation, were related to Behavioral Activation System (BAS) scores, which index approach-motivational tendencies. Results show that the pattern observed in righthanders reverses in left-handers, whose right hemisphere is specialized for both approach motivation and for control of dominant-hand actions. This anatomical covariation suggests a functional link between affective motivation and motor control, and also provides information crucial for developing neural therapies for affective disorders.

Development and early focal brain injury 2 Over the past ten years, we have made significant progress in addressing key questions concerning deficit and development after early stroke. We found evidence of subtle early impairment and subsequent development in each domain examined. However, the profiles of impairment and development differed across domains. Deficits of language acquisition are initially pervasive in that they are observed following injury to widely distributed brain areas. Spatial analytic deficits exhibit more specific patterns of brain-behavior association, similar to those observed among adults with injury to comparable brain regions. Had we been working in isolation, the separate investigators associated with this project may have reached very different conclusions about the nature of development following early injury. Instead, we were forced to look for ways to resolve the apparent disparity in our cross-domain findings. The model that best fits our data focuses on redefining the nature of early plasticity. Recent animal studies provide strong evidence that plasticity plays a central role in brain development. Brain organization is to a large extent

Do people with different kinds of bodies think differently? According to the body-specificity hypothesis, people who interact with their physical environments in systematically different ways should form correspondingly different mental representations. In a test of this hypothesis, 5 experiments investigated links between handedness and the mental representation of abstract concepts with positive or negative valence (e.g., honesty, sadness, intelligence). Mappings from spatial location to emotional valence differed between rightand left-handed participants. Right-handers tended to associate rightward space with positive ideas and leftward space with negative ideas, but left-handers showed the opposite pattern, associating rightward space with negative ideas and leftward with positive ideas. These contrasting mental metaphors for valence cannot be attributed to linguistic experience, because idioms in English associate good with right but not with left. Rather, right- and left-handers implicitly associated positive valence more strongly with the side of space on which they could act more fluently with their dominant hands. These results support the body-specificity hypothesis and provide evidence for the perceptuomotor basis of even the most abstract ideas.