Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
2,731
result(s) for
"Galvanic Skin Response"
Sort by:
Effects of Cortisol on Reconsolidation of Reactivated Fear Memories
by
Merz, Christian J
,
Tegenthoff, Martin
,
Wolf, Oliver T
in
Adolescent
,
Adult
,
Conditioning (Psychology) - drug effects
2015
The return of conditioned fear after successful extinction (eg, following exposure therapy) is a significant problem in the treatment of anxiety disorders and posttraumatic stress disorder (PTSD). Targeting the reconsolidation of fear memories may allow a more lasting effect as it intervenes with the original memory trace. Indeed, several pharmacological agents and behavioral interventions have been shown to alter (enhance, impair, or otherwise update) the reconsolidation of reactivated memories of different types. Cortisol is a stress hormone and a potent modulator of learning and memory, yet its effects on fear memory reconsolidation are unclear. To investigate whether cortisol intervenes with the reconsolidation of fear memories in healthy males and how specific this effect might be, we built a 3-day reconsolidation design with skin conductance response (SCR) as a measure of conditioned fear: Fear acquisition on day 1; reactivation/no-reactivation of one conditioned stimulus and pharmacological intervention on day 2; extinction learning followed by reinstatement and reinstatement test on day 3. The groups differed only in the experimental manipulation on day 2: Reactivation+Cortisol Group, Reactivation+Placebo Group, or No-reactivation+Cortisol Group. Our results revealed an enhancing effect of cortisol on reconsolidation of the reactivated memory. The effect was highly specific, strengthening only the memory of the reactivated conditioned stimulus and not the non-reactivated one. Our findings are in line with previous findings showing an enhancing effect of behavioral stress on the reconsolidation of other types of memories. These results have implications for the understanding and treatment of anxiety disorders and PTSD.
Journal Article
Exploring physiological stress response evoked by passive translational acceleration in healthy adults: a pilot study utilizing electrodermal activity and heart rate variability measurements
2024
Passive translational acceleration (PTA) has been demonstrated to induce the stress response and regulation of autonomic balance in healthy individuals. Electrodermal activity (EDA) and heart rate variability (HRV) measurements are reliable indicators of the autonomic nervous system (ANS) and can be used to assess stress levels. The objective of this study was to investigate the potential of combining EDA and HRV measurements in assessing the physiological stress response induced by PTA. Fourteen healthy subjects were randomly assigned to two groups of equal size. The experimental group underwent five trials of elevator rides, while the control group received a sham treatment. EDA and HRV indices were obtained via ultra-short-term analysis and compared between the two groups to track changes in the ANS. In addition, the complexity of the EDA time series was compared between the 4 s before and the 2–6 s after the onset of PTA to assess changes in the subjects' stress levels in the experimental group. The results revealed a significant increase in the skin conductance response (SCR) frequency and a decrease in the root mean square of successive differences (RMSSD) and high frequency (HF) components of HRV. In terms of stress assessment, the results showed an increase in the complexity of the EDA time series 2–6 s after the onset of PTA. These results indicate an elevation in sympathetic tone when healthy subjects were exposed to a translational transport scenario. Furthermore, evidence was provided for the ability of EDA complexity to differentiate stress states in individual trials of translational acceleration.
Journal Article
Autonomous nervous system responses to environmental‐level exposure to 5G's first deployed band (3.5 GHz) in healthy human volunteers
by
Mazet, Paul
,
Bach, Véronique
,
Hugueville, Laurent
in
Adult
,
Autonomic Nervous System - physiology
,
autonomous nervous system
2024
Following the global progressive deployment of 5G networks, considerable attention has focused on assessing their potential impact on human health. This study aims to investigate autonomous nervous system changes by exploring skin temperature and electrodermal activity (EDA) among 44 healthy young individuals of both sexes during and after exposure to 3.5 GHz antenna‐emitted signals, with an electrical field intensity ranging from 1 to 2 V/m. The study employed a randomized, cross‐over design with triple‐blinding, encompassing both ‘real’ and ‘sham’ exposure sessions, separated by a maximum interval of 1 week. Each session comprised baseline, exposure and postexposure phases, resulting in the acquisition of seven runs. Each run initiated with a 150 s segment of EDA recordings stimulated by 10 repeated beeps. Subsequently, the collected data underwent continuous decomposition analysis, generating specific indicators assessed alongside standard metrics such as trough‐to‐peak measurements, global skin conductance and maximum positive peak deflection. Additionally, non‐invasive, real‐time skin temperature measurements were conducted to evaluate specific anatomical points (hand, head and neck). The study suggests that exposure to 3.5 GHz signals may potentially affect head and neck temperature, indicating a slight increase in this parameter. Furthermore, there was a minimal modulation of certain electrodermal metrics after the exposure, suggesting a potentially faster physiological response to auditory stimulation. However, while the results are significant, they remain within the normal physiological range and could be a consequence of an uncontrolled variable. Given the preliminary nature of this pilot study, further research is needed to confirm the effects of 5G exposure. What is the central question of this study? Does autonomous nervous system activity, represented by skin temperature and electrodermal activity, change during and after exposure to 3.5 GHz antenna‐emitted signals typical of 5G mid‐band frequencies? What is the main finding and its importance? Head temperature significantly increased after exposure to 3.5 GHz signals, while neck temperature rose both during and after the exposure. Furthermore, a subtle but significant change in certain electrodermal parameters (CDA. Tonic activity as well as CDA and TTP Lateny) was detected following exposure, suggesting a potentially faster physiological response to auditory stimuli. However, while the findings are noteworthy, they remain within the normal physiological range and could be influenced by an uncontrolled factor.
Journal Article
Neural Underpinnings of Cortisol Effects on Fear Extinction
by
Hamacher-dang, Tanja Christina
,
Hermann, Andrea
,
Wolf, Oliver Tobias
in
Amygdala
,
Conductance
,
Extinction behavior
2018
Extinction of conditioned fear embodies a crucial mechanism incorporated in exposure therapy. Clinical studies demonstrated that application of the stress hormone cortisol before exposure sessions facilitates exposure success, but the underlying neural correlates remain unknown. Context- and stimulus-dependent cortisol effects on extinction learning will be characterized in this study and tested in the extinction and in a new context. Forty healthy men participated in a 3-day fear conditioning experiment with fear acquisition in context A (day 1), extinction training in context B (day 2), and recall in context B and a new context C one week later (day 3). Hydrocortisone (30 mg) or placebo was given before extinction training. Blood-oxygen-level-dependent responses and skin conductance responses (SCRs) served as dependent measures. At the beginning of extinction training, cortisol reduced conditioned SCRs, diminished activation of the amygdala-hippocampal complex, and enhanced functional connectivity of the anterior parahippocampal gyrus with the ventromedial prefrontal cortex (vmPFC). After one week, the cortisol group showed increased hippocampal activation and connectivity to the vmPFC toward an extinguished stimulus and reduced insula activation toward a nonextinguished stimulus in the extinction context. However, this inhibitory cortisol effect did not extend to the new context. Taken together, cortisol reduced fear recall at the beginning of extinction and facilitated the consolidation of the extinction memory as evidenced by an inhibitory activation pattern one week later. The stress hormone exerted a critical impact on the amygdala-hippocampus-vmPFC network underlying fear and extinction memories. However, cortisol did not attenuate the context dependency of extinction.
Journal Article
Skin conductance response to the pain of others predicts later costly helping
2011
People show autonomic responses when they empathize with the suffering of another person. However, little is known about how these autonomic changes are related to prosocial behavior. We measured skin conductance responses (SCRs) and affect ratings in participants while either receiving painful stimulation themselves, or observing pain being inflicted on another person. In a later session, they could prevent the infliction of pain in the other by choosing to endure pain themselves. Our results show that the strength of empathy-related vicarious skin conductance responses predicts later costly helping. Moreover, the higher the match between SCR magnitudes during the observation of pain in others and SCR magnitude during self pain, the more likely a person is to engage in costly helping. We conclude that prosocial motivation is fostered by the strength of the vicarious autonomic response as well as its match with first-hand autonomic experience.
Journal Article
Influence of Δ9-tetrahydrocannabinol on long-term neural correlates of threat extinction memory retention in humans
2019
The neural mechanisms and durability of Δ9-tetrahydrocannabinol (THC) impact on threat processing in humans are not fully understood. Herein, we used functional MRI and psychophysiological tools to examine the influence of THC on the mechanisms of conditioned threat extinction learning, and the effects of THC on extinction memory retention when assessed 1 day and 1 week from learning. Healthy participants underwent threat conditioning on day 1. On day 2, participants were randomized to take one pill of THC or placebo (PBO) 2-h before threat extinction learning. Extinction memory retention was assessed 1 day and 1 week after extinction learning. We found that THC administration increased amygdala and ventromedial prefrontal cortex (vmPFC) activation during early extinction learning with no significant impact on skin conductance responses (SCR). When extinction memory retention was tested 24 h after learning, the THC group exhibited lower SCRs to the extinguished cue with no significant extinction-induced activations within the extinction network. When extinction memory retention was tested 1 week after learning, the THC group exhibited significantly decreased responses to the extinguished cues within the vmPFC and amygdala, but significantly increased functional coupling between the vmPFC, hippocampus, and dorsal anterior cingulate cortex during this extinction retention test. Our results are the first to report a long-term impact of one dose of THC on the functional activation of the threat extinction network and unveil a significant change in functional connectivity emerging after a week from engagement. We highlight the need for further investigating the long-term impact of THC on threat and anxiety circuitry.
Journal Article
Noninvasive vagus nerve stimulation alters neural response and physiological autonomic tone to noxious thermal challenge
2019
The mechanisms by which noninvasive vagal nerve stimulation (nVNS) affect central and peripheral neural circuits that subserve pain and autonomic physiology are not clear, and thus remain an area of intense investigation. Effects of nVNS vs sham stimulation on subject responses to five noxious thermal stimuli (applied to left lower extremity), were measured in 30 healthy subjects (n = 15 sham and n = 15 nVNS), with fMRI and physiological galvanic skin response (GSR). With repeated noxious thermal stimuli a group × time analysis showed a significantly (p < .001) decreased response with nVNS in bilateral primary and secondary somatosensory cortices (SI and SII), left dorsoposterior insular cortex, bilateral paracentral lobule, bilateral medial dorsal thalamus, right anterior cingulate cortex, and right orbitofrontal cortex. A group × time × GSR analysis showed a significantly decreased response in the nVNS group (p < .0005) bilaterally in SI, lower and mid medullary brainstem, and inferior occipital cortex. Finally, nVNS treatment showed decreased activity in pronociceptive brainstem nuclei (e.g. the reticular nucleus and rostral ventromedial medulla) and key autonomic integration nuclei (e.g. the rostroventrolateral medulla, nucleus ambiguous, and dorsal motor nucleus of the vagus nerve). In aggregate, noninvasive vagal nerve stimulation reduced the physiological response to noxious thermal stimuli and impacted neural circuits important for pain processing and autonomic output.
Journal Article
Psychological and physiological effects of applying self-control to the mobile phone
2019
This preregistered study examined the psychological and physiological consequences of exercising self-control with the mobile phone. A total of 125 participants were randomly assigned to sit in an unadorned room for six minutes and either (a) use their mobile phone, (b) sit alone with no phone, or (c) sit with their device but resist using it. Consistent with prior work, participants self-reported more concentration difficulty and more mind wandering with no device present compared to using the phone. Resisting the phone led to greater perceived concentration abilities than sitting without the device (not having external stimulation). Failing to replicate prior work, however, participants without external stimulation did not rate the experience as less enjoyable or more boring than having something to do. We also observed that skin conductance data were consistent across conditions for the first three-minutes of the experiment, after which participants who resisted the phone were less aroused than those who were without the phone. We discuss how the findings contribute to our understanding of exercising self-control with mobile media and how psychological consequences, such as increased mind wandering and focusing challenges, relate to periods of idleness or free thinking.
Journal Article
Emotional reactivity and interoceptive sensitivity: Exploring the role of age
by
Mikkelsen, Mai Bjørnskov
,
Lyby, Marlene Skovgaard
,
Wallot, Sebastian
in
Adult
,
Age differences
,
Age Factors
2019
Interoceptive sensitivity
(IS) refers to the ability to accurately perceive visceral afferent information, and several prominent theories of emotions suggest that IS is associated with heightened emotional reactivity. Recent evidence has pointed to a decline in IS with age, but there is no consistent evidence of age-related decline in emotional reactivity. This may be because the relationship between IS and emotional reactivity changes with age. To address this hypothesis, we examined the moderating role of age in the association between IS and emotional responses to affect-inducing images. A sample of 65 young adults (mean age = 23.91 years,
SD
= 4.62) and 32 older adults (mean age = 61.78 years,
SD
= 8.76) was exposed to affect-inducing images from the Nencki Affective Picture System database and completed a heartbeat perception task. Participants’ subjective emotional responses to the images were assessed with questionnaires, and their physiological reactivity was indicated by electrodermal activity, heart rate, and heart rate variability during image viewing. The results revealed that age moderated the association between IS and emotional reactivity, while no significant age differences were found in IS, change in affect, or physiological reactivity. The findings demonstrated that IS was associated with emotional reactivity for young adults but not for older adults, suggesting that young and older adults may differ in their use of internal bodily signals to obtain information about their emotional experience. Consistent with contemporary developments within the affective sciences, the results emphasize the importance of individual differences in emotional experiences.
Journal Article
Randomized controlled trial of individualized arousal-biofeedback for children and adolescents with disruptive behavior disorders (DBD)
by
Baumeister, Sarah
,
Kaiser, Anna
,
Walitza, Susanne
in
Adolescents
,
Aggression
,
Aggressive behavior
2024
Disruptive behavior disorders [including conduct disorder (CD) and oppositional defiant disorder (ODD)] are common childhood and adolescent psychiatric conditions often linked to altered arousal. The recommended first-line treatment is multi-modal therapy and includes psychosocial and behavioral interventions. Their modest effect sizes along with clinically and biologically heterogeneous phenotypes emphasize the need for innovative personalized treatment targeting impaired functions such as arousal dysregulation. A total of 37 children aged 8–14 years diagnosed with ODD/CD were randomized to 20 sessions of individualized arousal biofeedback using skin conductance levels (SCL-BF) or active treatment as usual (TAU) including psychoeducation and cognitive–behavioral elements. The primary outcome was the change in parents´ ratings of aggressive behavior measured by the Modified Overt Aggression Scale. Secondary outcome measures were subscales from the Child Behavior Checklist, the Inventory of Callous-Unemotional traits, and the Reactive-Proactive Aggression Questionnaire. The SCL-BF treatment was neither superior nor inferior to the active TAU. Both groups showed reduced aggression after treatment with small effects for the primary outcome and large effects for some secondary outcomes. Importantly, successful learning of SCL self-regulation was related to reduced aggression at post-assessment. Individualized SCL-BF was not inferior to active TAU for any treatment outcome with improvements in aggression. Further, participants were on average able to self-regulate their SCL, and those who best learned self-regulation showed the highest clinical improvement, pointing to specificity of SCL-BF regulation for improving aggression. Further studies with larger samples and improved methods, for example by developing BF for mobile use in ecologically more valid settings are warranted.
Journal Article