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Roelofs, K.

Publications and source records attributed to Roelofs, K..

2 recordsLinked to original sources

Eye-movement intervention enhances extinction via amygdala deactivation

Improving extinction learning is essential to optimize psychotherapy for persistent fear-related disorders. In two independent studies (both n=24), we found that goal-directed eye movements activate a dorsal fronto-parietal network and transiently deactivate the amygdala. Connectivity analyses revealed this down-regulation engages a ventromedial prefrontal pathway known to be involved in cognitive regulation of emotion. Critically, when eye movements followed memory reactivation during extinction learning, this reduced spontaneous fear recovery 24 hours later. Stronger amygdala deactivation furthermore predicted a stronger reduction in subsequent fear recovery after reinstatement. In conclusion, we show that extinction learning can be improved with a non-invasive eye-movement intervention that triggers a transient suppression of the amygdala. Our finding that another task which taxes working memory leads to a similar amygdala suppression furthermore indicates that this effect is likely not specific to eye movements, which is in line with a large body of behavioral studies. This study contributes to the understanding of a widely used treatment for traumatic symptoms by providing a parsimonious account for how working memory tasks and goal-directed eye movements can enhance extinction-based psychotherapy, namely through neural circuits similar to those that support cognitive control of emotion.\n\nSignificant statementFear-related disorders represent a significant burden on individual sufferers and society. There is a high need to optimize treatment, in particular via non-invasive means. One potentially effective intervention is execution of eye movements following trauma recall. However, a neurobiological understanding of how eye movements can reduce traumatic symptoms is lacking. We demonstrate that goal-directed eye-movements, like working memory tasks, deactivate the amygdala, the core neural substrate of fear learning. Effective connectivity analyses revealed amygdala deactivation engaged dorsolateral and ventromedial prefrontal pathways. When applied during safety learning, this deactivation predicts a reduction in later fear recovery. These findings provide a parsimonious and mechanistic account of how behavioral manipulations taxing working memory and suppress amygdala activity can alter retention of emotional memories.

neuroscience

Stress matters: a double-blind, randomized controlled trial on the effects of a multispecies probiotic on neurocognition

Probiotics are microorganisms that can provide health benefits when consumed. Recent animal studies have demonstrated that probiotics can reverse gut microbiome-related alterations in anxiety and depression-like symptoms, in hormonal responses to stress, and in cognition. However, in humans, the effects of probiotics on neurocognition remain poorly understood and a causal understanding of the gut-brain link in emotion and cognition is lacking. We aimed to fill this gap by studying the effects of a probiotics intervention versus placebo on neurocognition in healthy human volunteers.\n\nWe set out to investigate the effects of a multispecies probiotic (Ecologic(R)Barrier) on specific neurocognitive measures of emotion reactivity, emotion regulation, and cognitive control using fMRI. Critically, we also tested whether the use of probiotics can buffer against the detrimental effects of acute stress on working memory. In a double blind, randomized, placebo-controlled, between-subjects intervention study, 58 healthy participants were tested twice, once before and once after 28 days of intervention with probiotics or placebo.\n\nProbiotics versus placebo did not affect emotion reactivity, emotion regulation, and cognitive control processes at brain or behavioral level, neither related self-report measures. However, relative to the placebo group, the probiotics group did show a significant stress-related increase in working memory performance after versus before supplementation (digit span backward, p=0.039, {eta}p2=.07). Interestingly, this change was associated with intervention-related neural changes in frontal cortex during cognitive control in the probiotics group, but not in the placebo group. Overall, our results show that neurocognitive effects of supplementation with a multispecies probiotic in healthy women become visible under challenging (stress) situations. Probiotics buffered against the detrimental effects of stress in terms of cognition, especially in those individuals with probiotics-induced changes in frontal brain regions during cognitive control.\n\nHighlightsO_LIWe ran a randomized placebo-controlled fMRI study with a multispecies probiotic\nC_LIO_LIProbiotics did not affect neurocognitive measures of emotion and cognitive control\nC_LIO_LIProbiotics did affect stress-related working memory and neural correlates\nC_LIO_LIProbiotics in healthy individuals can support cognition under stress\nC_LI

neuroscience