Impact of long-term meditation practice on cardiovascular reactivity during perception and reappraisal of affective images.

Meditation has been found to be an efficient strategy for coping with stress in healthy individuals and in patients with psychosomatic disorders. The main objective of the present study was to investigate the psychophysiological mechanisms of beneficial effects of meditation on cardiovascular reactivity. We examined effects of long-term Sahaja Yoga meditation on cardiovascular reactivity during affective image processing under "unregulated" and "emotion regulation" conditions. Twenty two experienced meditators and 20 control subjects participated in the study. Under "unregulated" conditions participants were shown neutral and affective images and were asked to attend to them. Under "emotion regulation" conditions they down-regulated negative affect through reappraisal of negative images or up-regulated positive affect through reappraisal of positive images. Under "unregulated" conditions while anticipating upcoming images meditators vs. controls did not show larger pre-stimulus total peripheral resistance and greater cardiac output for negative images in comparison with neutral and positive ones. Control subjects showed TPR decrease for negative images only when they consciously intended to reappraise them (i.e. in the "emotion regulation" condition). Both meditators and controls showed comparable cardiovascular reactivity during perception of positive stimuli, whereas up-regulating of positive affect was associated with more pronounced cardiac activation in meditators. The findings provide some insight into understanding the beneficial influence of meditation on top-down control of emotion and cardiovascular reactivity.

The temporal dynamics of cognitive reappraisal: cardiovascular consequences of downregulation of negative emotion and upregulation of positive emotion.

This study examines the effects of cognitive reappraisal on the cardiovascular response to affective stimuli. Participants (N = 53) were shown affective images and were asked either to attend to the images, or to downregulate negative affect through reappraisal of negative images or upregulate positive affect through reappraisal of positive images while continuous measures of cardiovascular activity were recorded. Reappraisal of negative images was associated with lower total peripheral resistance and larger cardiac output in the prestimulus period, whereas reappraisal of positive images was associated with less pronounced decreases of heart rate, cardiac output, and mean blood pressure in the viewing period as compared to unregulated conditions. The results indicate that cognitive reappraisal engenders adaptive hemodynamic profiles both during anticipation and during viewing of affective images depending on their valence and the regulatory goal.

Trait anxiety impact on the EEG theta band power changes during appraisal of threatening and pleasant visual stimuli.

The main objective of the present investigation was to examine whether trait anxiety construct would influence EEG event-related synchronization (ERS) of the theta power during viewing of visual threatening stimuli. The 62-channel EEG was recorded while low (LA, n= 18) and high (HA, n= 18) trait-anxious subjects viewed sequentially presented neutral, threatening and pleasant pictures. Between-group differences, related to stimulus emotionality, were linked to the test period of 0-1000 ms after stimulus onset. In the low theta (4-6 Hz) at prefrontal sites HA exhibited deficient ERS in response to both threatening and pleasant stimuli in the right hemisphere, whereas LA yielded larger right than left hemisphere ERS in response to all the three stimulus categories. In the upper theta (6-8 Hz) group differences were associated with posterior cortical regions: HA exhibited the largest ERS to threatening and the lowest to pleasant stimuli, whereas LA prompted the largest ERS to pleasant and the lowest to neutral pictures. It is suggested that low theta right prefrontal hypoactivation favoring left hemispheric (i.e. more analytical) activity along with higher upper theta ERS of posterior cortical regions (i.e. enhanced higher order visual processing) to threatening stimuli could form the basis for neuropsychologically observed general bias towards threatening information in HA.