Stop looking angry and smile, please: start and stop of the very same facial expression differentially activate threat- and reward-related brain networks

Static pictures of emotional facial expressions have been found to activate brain structures involved in the processing of emotional stimuli. However, in everyday live, emotional expressions are changing rapidly, and the processing of the onset vs the offset of the very same emotional expression might rely on different brain networks, presumably leading to different behavioral and physiological reactions (e.g. approach or avoidance). Using functional magnetic resonance imaging, this was examined by presenting video clips depicting onsets and offsets of happy and angry facial expressions. Subjective valence and threat ratings clearly depended on the direction of change. Blood oxygen level dependent responses indicate both reward- and threat-related activations for the offset of angry expressions. Comparing onsets and offsets, angry offsets were associated with stronger ventral striatum activation than angry onsets. Additionally, the offset of happy and the onset of angry expressions showed strong common activity in the lateral orbitofrontal cortex bilaterally, the left amygdala and the left insula, whereas the onset of happy and the offset of angry expressions induced significant activation in the left dorsal striatum. In sum, the results confirm different activity in motivation-related brain areas in response to the onset and offset of the same emotional expression and highlight the importance of temporal characteristics of facial expressions for social communication

Using the HOME Inventory with Infants in Costa Rica

This study determined the psychometric properties of the HOME (Home Observation for Measurement of the Environment) Inventory in a Latin American sample. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardisation sample from Little Rock. The Costa Rican total HOME average of 29.8 ± 6.7 was similar to the scores of families in Little Rock (mean = 31.2 ± 7.3). Measures or internal consistency and factor structure were similar in US and Costa Rican samples. In contrast to these similarities, Costa Rican HOME scores showed no significant correlation with developmental test scores in infancy (Bayley MDI), and the correlation with Full Scale IQ (WPPSI) at five years was modest, albeit statistically significant (r = 0.28, P < 0.05). These relationships were similar to those of Mexican-American children in a recent collaborative study by Bradley et al., 1989 and not as strong as for US white and black populations. However, when the concept of outcome was broadened beyond IQ scores to include child health and development in general, the HOME seemed sensitive to important environmental differences in this Costa Rican group. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anaemia in infancy, a condition associated with long-lasting developmental disadvantage. Thus, the HOME was helpful in identifying children at risk for delayed development in this Latin American sample.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67767/2/10.1177_016502549501800206.pd