Mark H McManis | PubMed Health

PubMed2006

Time-locked brain activity associated with emotion: a pilot MEG study.

OBJECTIVE: To examine the time course of brain activation in response to emotionally evocative pictures. METHODS AND PROCEDURES: Regions of the brain involved in the processing of affective stimuli in response to picture sets rated unpleasant, pleasant and affectively neutral, as well as the order of activation of each region, were investigated using magnetoencephalography in 10 normal adult volunteers. RESULTS: Spatiotemporal maps were found consisting of two basic components. The first involving activation in the occipital and basal aspects of the temporal cortex- lasted, on average, 270 ms post-stimulus. The second component involving activation in the mesial temporal lobes (MTL) extended from 270 to 850 ms post-stimulus. After (serial) activating the mesial temporal lobe structures or simultaneous (parallel) to it, activation is also observed in the frontal structures. CONCLUSIONS: The temporal organization in the brain of an emotional stimulus requires the serial and alternating engagement of frontal and posterior cortices. It is suggested that lesions to the brain may disrupt this temporal course, altering the emotional response commonly observed in patients with brain injury.

Adult↗

PubMed2002

EEG asymmetry, power, and temperament in children.

Measures of EEG spectral power, lateral asymmetry in the frontal and parietal areas, and social behavior with an examiner were analyzed on 166 children, 10 to 12 years old, who were participating in a longitudinal study of the temperamental contributions to social behavior. Loss of 8- to 13-Hz power (alpha band) on the right, compared with the left, frontal area (right frontal active) was most prevalent among children who were classified as high reactive at 4 months and were highly fearful at 14 and 21 months. Second, greater frontal power in the 14- to 30-Hz band (beta) at rest was correlated with the tendency to be right frontal active. Finally, spontaneous talkativeness with an unfamiliar examiner was associated with right frontal activation and high alpha power for boys, but with right frontal activation and high beta power for girls. Right frontal activation is most characteristic of children who begin life with a temperamental bias favoring high reactivity and who develop a fearful reaction to unfamiliar events in the second year of life.

Brain↗