Neural Mechanisms Underlying 5-HTTLPR-Related Sensitivity to Acute Stress

Abstract

Objective Many studies have shown that 5-HTTLPR genotype interacts with exposure to stress in conferring risk for psychopathology. However, the specific neural mechanisms through which this gene-by-environment interaction confers risk remain largely unknown, and no study to date has directly examined the modulatory effects of the 5-HTTLPR on corticolimbic circuit responses during exposure to acute stress. Methods An acute laboratory stressor was administered to 51 healthy women during BOLD fMRI scanning. In this task, electric shocks of uncertain intensity were threatened and unpredictably delivered to the wrist after a long anticipatory cue period of unpredictable duration. Results Relative to those carrying the L allele, SS homozygotes showed enhanced activation during threat anticipation in a network of regions including amygdala, hippocampus, anterior insula, thalamus, pulvinar, caudate, precuneus, anterior cingulate cortex, and medial prefrontal cortex. SS homozygotes also displayed enhanced positive coupling between medial prefrontal cortex activation and anxiety experience, whereas individuals carrying the L allele displayed enhanced negative coupling between insula activation and perceived success at regulating anxiety. Conclusions The present findings suggest that, when exposed to stress, SS homozygotes may preferentially engage neural systems which enhance fear and arousal, modulate attention toward threat, and perseverate on emotional salience of the threat. This may be one mechanism underlying risk for psychopathology conferred by the S allele upon exposure to life stressors.

Stress pulls us apart: Anxiety leads to differences in competitive confidence under stress

“…Indeed, behavioral and cognitive effects of stress are believed to result from alterations on the activity of largescale brain networks (Drabant et al, 2012;Gathmann et al, 2014;Hermans et al, 2011). Differences in trait anxiety can result in different physiological stress responses (Sandi and Richter-Levin, 2009); however, they do not seem to account for the observed differences in competitive decisions.…”

The Motivated Gatekeeper of Our Minds

“…In terms of affective mechanisms, we have already discussed how NFC is characterized by aversion and distress in the face of uncertainty and ambiguity, evidenced, for example, by the psychophysiological findings of . Of special relevance to the genetic underpinnings of NFC, previous research has shown that possessing a short-allele (vs. long-allele) of the serotonin transporter gene (5-HTTLPR) is associated with greater emotional reactivity to uncertain, ambiguous, and unfamiliar situations (e.g., Drabant et al, 2012;Heinz et al, 2007). Hence, short-allele (vs. long-allele) carriers may also show higher levels of NFC.…”

Biology of Stress and Physical Performance

“…[5]. In long-distance athletes, the changing situations in the course of training and competition, together with the presence of anxiety disorders, could be caused by maladaptive fatigue syndrome (overtraining syndrome) characterized by anger, hostility, anxiety, confusion, depression, sadness, lack of energy, and apathy, which has as a consequence of a bad performance and/or the abandonment of training and skills [3,8,9].…”

“…The model of mental health and sports performance suggests that there is an inverse relationship between psychopathology and sports performance [9]. This model postulates that as an athlete's mental health deteriorates or improves performance it must fall or rise accordingly [3,8].…”

“…Research indicates that responses of athletes' mood states exhibit a dose-response relationship with their training load; this inding has shown potential to reduce the incidence of overtraining syndrome in athletes who undergo rigorous physical training [3]. Other studies show a deleterious efect of stress and anxiety on sports performance in various sports [3,4,8,9]. …”