Biological psychology
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Biological psychology · Dec 2013
Do sex hormones influence emotional modulation of pain and nociception in healthy women?
Sex hormones may contribute to inter- and intra-individual differences in pain by influencing emotional modulation of pain and nociception. To study this, a well-validated picture-viewing paradigm was used to assess emotional modulation of pain and the nociceptive flexion reflex (NFR; physiologic measure of nociception) during mid-follicular, ovulatory, and late-luteal phases of the menstrual cycle in healthy normally cycling women (n=40). ⋯ Given evidence that a failure to emotionally modulate pain might be a risk factor for chronic pain, low estradiol may promote chronic pain via this mechanism. However, future research is needed to extend these findings to women with disturbances of pain, emotion, and/or sex hormones.
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Biological psychology · Oct 2013
An increase in salivary interleukin-6 level following acute psychosocial stress and its biological correlates in healthy young adults.
Although interleukin-6 (IL-6) has been investigated frequently in stress research, knowledge regarding the biological processes of IL-6 in association with psychosocial stress remains incomplete. This study focused on salivary IL-6 and reports its temporal variation and biological correlates following acute psychosocial stress. Fifty healthy young adults (39 male and 11 female students) were subjected to the psychosocial stress test 'Trier Social Stress Test' (TSST), wherein the participants were asked to deliver a speech and perform a mental arithmetic task in front of 2 audiences. ⋯ Cluster analyses revealed that individuals with sustained elevation of IL-6 levels following the TSST exhibited a lower cortisol response compared to individuals with lower IL-6 levels. In the correlation analyses, a greater IL-6 response was associated with a higher heart rate during the mental arithmetic task (r=.351, p<.05) and with a lower cortisol response (r=-.302, p<.05). This study demonstrates that salivary IL-6 levels are elevated for a relatively long period following acute psychosocial stress, and suggests that sympathetic activity and cortisol secretion are involved in elevation of salivary IL-6 levels.
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Biological psychology · Oct 2013
Evening-type military veterans report worse lifetime posttraumatic stress symptoms and greater brainstem activity across wakefulness and REM sleep.
Evening chronotypes exhibit increased rates of affective dyregulation and sleep disturbances (e.g., insomnia and nightmares). Such symptoms are common to military veterans with posttraumatic stress disorder (PTSD); however, the influence of chronotype on this population remains unknown. We examined behavioral, psychological, and neural correlates of chronotype in 36 combat-exposed military veterans with varying degrees of posttraumatic stress symptomatology. ⋯ Eveningness was also associated with greater brain activity in posterior cingulate/precuneus and brainstem regions across wakefulness and REM sleep, overlapping with regions related to arousal and REM sleep generation. Chronotype may be an important correlate of neural activity in REM sleep-generating and/or arousal regulatory regions among combat-exposed veterans with PTSD symptoms. Further investigations of the role of chronotype in PTSD are warranted.
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Biological psychology · Sep 2013
Self- or parent report of (co-occurring) internalizing and externalizing problems, and basal or reactivity measures of HPA-axis functioning: a systematic evaluation of the internalizing-hyperresponsivity versus externalizing-hyporesponsivity HPA-axis hypothesis.
Previous research findings on the link between adolescents' psychopathology and hypothalamic-pituitary-adrenal (HPA) axis activity have been heterogeneous. ⋯ Only in the context of stress, and particularly when based on self-report, blunted cortisol output was associated with externalizing and enhanced cortisol output with internalizing problems. Our broad approach demonstrates the importance of who reports on psychopathology, the use of dimensional measures of psychopathology, simultaneous analysis of internalizing and externalizing problems, and the use of awakening and social stress related measures of cortisol.
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Biological psychology · Sep 2013
Neural time course of threat-related attentional bias and interference in panic and obsessive-compulsive disorders.
Attentional biases to threat are considered central to anxiety disorders, however physiological evidence of their nature and time course is lacking. Event-related potentials (ERPs) characterized sensory and cognitive changes while 20 outpatients with panic disorder (PD), 20 with obsessive-compulsive disorder (OCD), and 20 healthy controls (HCs) responded to the color (emotional Stroop task) or meaning of threatening and neutral stimuli. ERPs indicated larger P1 amplitude and longer N1 latency in OCD, and shorter P1 latency in PD, to threatening (versus neutral) stimuli, across instructions to attend to, or ignore, threat content. ⋯ Participants with emotional Stroop interference had augmented P1 and P3 amplitudes to threat (versus neutral) stimuli when color-naming. The results suggest early attentional biases to threat in both disorders, with disorder-specific characteristics. ERPs supported preferential early attentional capture and cognitive elaboration hypotheses of emotional Stroop interference.