2,P<0.05). Thus, the infant temperamental profiles predicted, to a modest degree, spontaneity or a subdued style

with the unfamiliar adult examiner. One half of the current group of high and low reactives had been seen when they were four and a half and seven and a half years of age. A similar rating of degree of anxiety/inhibition on a 4-point scale was assigned to each child based on 90 min of interaction with a different, but unfamiliar Selleckchem BI2536 female examiner. Inhibitors,research,lifescience,medical Seventy percent, of the low reactives, but only 13% of the high réactives were uninhibited at all three ages; 38% of high reactives, but only 6% of low reactives were inhibited at all three Inhibitors,research,lifescience,medical ages (chisquare=21.3, P<0.001). It was rare for a low-reactive infant to become a consistently inhibited child or for a high-reactive infant, to become a consistently

uninhibited child. As expected, the uninhibited profile was better preserved because family and friends encourage sociability and discourage shyness and timidity. Seven descriptive items on the maternal Q-sort referred to shyness or sociability in the child. We computed the mean ranks the mother assigned to her child for the three shy and the four sociable items. High reactives were described as more shy and less sociable than the low réactives (r(149)=3.91, P<0.01). Biological variables Figure Inhibitors,research,lifescience,medical 1 illustrates the mean standard scores for high and low reactives on the four biological variables at 11 years of age: right parietal activation in the EEG, wave 5 magnitudes, sympathetic Inhibitors,research,lifescience,medical tone (a low ratio and a high resting heart rate), and the mean of the integrated voltages from 400 to 1000 ms for the event-related potential to

the first oddball flower and the novel invalid scenes. The high réactives had greater EEG activation at the right Inhibitors,research,lifescience,medical parietal site (r(152)=2.53, P<0.05). Further, the high reactives who had been highly fearful in the second year showed greater activation in the right frontal area compared with low reactives who were equally fearful in the second year. The high reactives also had significantly larger wave 5 values (r(125)=2.87, P<0.05), and this variable Casein kinase 1 best separated the two temperamental groups.19 Figure 1 Mean standard score for four biological variables for 11-year-old children who were classified as high or low reactive at 4 months. The high reactives also had greater sympathetic tone in the cardiovascular system; 49% of high reactives, but only 32% of low reactives, combined a low ratio in the spectral analysis with a high resting heart rate; 32% of the low réactives, but only 16% of high réactives, combined a high ratio with a low resting heart, rate (chisquare=4.9, P<0.05). It is also of interest that high sympathetic tone was the best correlate of behavior.