Temporal dynamics of emotional responding: amygdala recovery predicts emotional traits

An individual’s affective style is influenced by many things, including the manner in which an individual responds to an emotional challenge. Emotional response is composed of a number of factors, two of which are the initial reactivity to an emotional stimulus and the subsequent recovery once the stimulus terminates or ceases to be relevant. However, most neuroimaging studies examining emotional processing in humans focus on the magnitude of initial reactivity to a stimulus rather than the prolonged response. In this study, we use functional magnetic resonance imaging to study the time course of amygdala activity in healthy adults in response to presentation of negative images. We split the amygdala time course into an initial reactivity period and a recovery period beginning after the offset of the stimulus. We find that initial reactivity in the amygdala does not predict trait measures of affective style. Conversely, amygdala recovery shows predictive power such that slower amygdala recovery from negative images predicts greater trait neuroticism, in addition to lower levels of likability of a set of social stimuli (neutral faces). These data underscore the importance of taking into account temporal dynamics when studying affective processing using neuroimaging

Analysis of two methods of isometric muscle contractions during the anti-G straining maneuver

This study investigated the difference in Mean Arterial Pressure (MAP) and Cardiac Output (CO) between two methods of isometric muscle contractions during the Anti-G Straining Maneuver (AGSM). 12 subjects (ages 18 to 38 yrs, height 176.8 +/- 7.4 cm, body mass 78.8 +/- 15.6 kg, percent body fat 14.3 +/- 6.6%) participated in the study. The study was a one-way within-subject design with test conditions counterbalanced. Two methods of isometric muscle contractions lasting 30 seconds each were assessed; an isometric push contraction and an isometric muscle tensing contraction. The dependent parameters were MAP and CO. The average MAP during the push contraction was 123 mmHg, SD +/- 11 and for tense was 118 mmHg, SD +/- 8. CO was 7.6 L/min, SD +/- 1.6 for push and 7.9 L/min, SD +/- 2.0 for tense method. Dependent t-tests revealed t(11) = 1.517, p = 0.157 for MAP and t(11) = 0.875, p = 0.400 for CO. This study demonstrated that the two methods of isometric muscle contractions were not statistically different with regards to MAP and CO. Therefore, both forms of isometric contractions may be potentially useful when performing the muscle contraction portion of the AGSM

Mindfulness video game improves connectivity of the fronto-parietal attentional network in adolescents: A multi-modal imaging study.

Mindfulness training has been shown to improve attention and change the underlying brain substrates in adults. Most mindfulness training programs involve a myriad of techniques, and it is difficult to attribute changes to any particular aspect of the program. Here, we created a video game, Tenacity, which models a specific mindfulness technique - focused attention on ones breathing - and assessed its potential to train an attentional network in adolescents. A combined analysis of resting state functional connectivity (rs-FC) and diffusion tensor imaging (DTI) yielded convergent results - change in communication within the left fronto-parietal network after two weeks of playing Tenacity compared to a control game. Rs-FC analysis showed greater connectivity between left dorsolateral prefrontal cortex (dlPFC) and left inferior parietal cortex (IPC) in the Tenacity group. Importantly, changes in left dlPFC - IPC rs-FC and changes in structural connectivity of the white matter tract that connects these regions -left superior longitudinal fasiculus (SLF) - were associated with changes in performance on an attention task. Finally, changes in left dlPFC - IPC rs-FC correlated with the change in left SLF structural connectivity as measured by fractional anisotropy (FA) in the Tenacity group only

Electromyographically assessed empathic concern and empathic happiness predict increased prosocial behavior in adults

a b s t r a c t The relation between empathy subtypes and prosocial behavior was investigated in a sample of healthy adults. "Empathic concern" and "empathic happiness", defined as negative and positive vicarious emotion (respectively) combined with an other-oriented feeling of "goodwill" (i.e. a thought to do good to others/see others happy), were elicited in 68 adult participants who watched video clips extracted from the television show Extreme Makeover: Home Edition. Prosocial behavior was quantified via performance on a non-monetary altruistic decision-making task involving book selection and donation. Empathic concern and empathic happiness were measured via self-report (immediately following each video clip) and via facial electromyography recorded from corrugator (active during frowning) and zygomatic (active during smiling) facial regions. Facial electromyographic signs of (a) empathic concern (i.e. frowning) during sad video clips, and (b) empathic happiness (i.e. smiling) during happy video clips, predicted increased prosocial behavior in the form of increased goodwill-themed book selection/donation