Effects of negative emotion and its correlated neural activity on secretory immunoglobulin A

In this study, we investigated how the negative emotional arousal induced by watching a number of unpleasant images altered the concentration of secretory immunoglobulin A (SIgA) in saliva. Although our results found discrepancies among participants’ SIgA concentration (i.e. some participants’ SIgA decreased after watching unpleasant pictures, whereas others increased), further analysis revealed correlations among participants’ changes in SIgA concentration, their general coping styles and their actual strategies for emotion regulation when perceiving unpleasant pictures, and the event-related potentials (ERPs) associated with viewing unpleasant pictures. The participants whose SIgA increased after watching unpleasant pictures (the "Increasers") had higher positive coping scores in the Trait Coping Styles Questionnaire (TCSQ) than those whose SIgA decreased (the "Decreasers"). Also, rela-tive to the "Decreasers",the "Increasers" tended to use more emotion regulation strategies, particu-larly with extremely negative pictures. The amplitude of their late positive potentials (LPPs) exhibited a reverse dissociation pattern for extremely negative pictures versus least negative ones and was related to the cognitive evaluation of the stimuli’s meaning. In sum, this research revealed the psychological mechanisms by which negative emotional states influence the immune system and the related ERP changes.

Neural substrates of global perception are modulated by local elem ent grouping

Prior behavioral studies suggested that global perception of compound stimuli is modulated by the way the local elements are grouped into global structures. The current work examined whether dis- tinct neural mechanisms are involved in global/local processing of compound stimuli when local elements are grouped into global shapes by proximity or by shape similarity. Functional magnetic resonance im- aging (fMRI) was used to measure neural activities associated with global/local processing of compound shapes that were presented against either a black background (Experiment 1) or a background of crosses (Experiment 2) while subjects discriminated close or open shapes at the global or local level. Global processing induced activation in the medial occipital cortex in Experiment 1 but in the right inferior temporal, superior parietal, and inferior frontal cortex, and the left inferior parietal gyrus in Experiment 2. Local processing was associated with activations in the left precentral gyrus and right superior temporal gurys in Experiment 1 but in the left posterior inferior parietal gyrus in Experiment 2. The fMRI results suggest that global perception is mediated by distinct neural substrates depending upon how local ele- ments are grouped into global structures.