The effects of lorazepam on skin conductance responses to aversive stimuli in healthy subjects

Heart Rate Variability: A Measure of Cardiovascular Health and Possible Therapeutic Target in Dysautonomic Mental and Neurological Disorders

Mental illness such as depression and anxiety as well as cerebrovascular disease are linked to impairment of neurocardiac function mediated by changes to the autonomic nervous system with increased sympathetic and decreased parasympathetic activity. Autonomic neurocardiac function can be evaluated by computing heart rate variability (HRV). Over the past decades, research has demonstrated the diagnostic value of HRV as independent predictor of cardiovascular mortality and as disease marker in progressive autonomic nervous system disorders such as Parkinson’s disease. Here we summarize our studies on HRV and its therapeutic modulation in the context of psychopharmacology as well as psychiatric and neurological disorders to honor the life of Professor Evgeny Vaschillo, the true pioneer of HRV research who sadly passed away on November 21st, 2020.

Skin conductance levels and responses in Asian and White participants during fear conditioning✰

Fear conditioning paradigms are frequently used in the translational study of anxiety and fear-related disorders. Accordingly, it is important to understand whether the measurement of fear conditioning responses is systematically influenced by an individual's race. Studies have found increased pain sensitivity and smaller physiological startle responses in Asian individuals, compared to White individuals; to our knowledge, no studies have evaluated whether skin conductance response (SCR) outcomes differ between Asian and White individuals. In a series of secondary data analyses, we investigated potential differences in skin conductance level (SCL), orienting SCR, unconditioned SCR, SCR to CS+ and CS-, differential SCR, and differential SCR non-responder status. In sample 1, Asian participants (n = 97) demonstrated a significantly smaller mean differential SCR compared to White participants (n = 86). No other between group differences were observed. In sample 2, there was no difference in mean differential SCR between Asian (n = 52) and White (n = 62) participants, although more Asian participants failed to show adequate skin conductance levels for study entry. To our knowledge, this is the first study to evaluate differences between Asian and White samples using skin conductance outcomes in a fear conditioning paradigm. We detected only subtle evidence for SCR differences between Asian and White samples, unlikely to reach significance outside large studies.

Measuring pain-Physiological and self-rated measurements in relation to pain stimulation and anxiety

INTRODUCTION

The aim of the present study was to investigate how emotions influence pain, measured by one subjective self-rated measure, the numeric rating scale (NRS), and one objective physiological measure, the number of skin conductance responses (NSCR).

METHOD

Eighteen volunteers were exposed to conditions with pictorial emotional stimuli (neutral, positive, negative), authentic ICU-sound (noise, no-noise) and electrical stimulation (pain, no-pain) individually titrated to induce moderate pain. When using all combinations of picture inducing emotions, sound, and pain, each of these conditions (12 conditions lasting for 60 seconds each) were followed by pain ratings. Ratings of arousal (low to high) and valence (pleasant to unpleasant) were used as indicators of affective state for each condition. Mean NSCR was also measured throughout the experiment for each condition.

RESULTS

Even though NRS and NSCR increased during painful stimuli, they did not correlate during the trial. However, NSCR was positively correlated with the strength of the electrical stimulation, r = 0.48, P = 0.046, whereas NRS showed positive correlations with the anxiety level, assessed by affective ratings (arousal, r = 0.61, P < 0.001, and valence, r = 0.37, P < 0.001).

CONCLUSIONS

The NRS was strongly influenced by affective state, with higher pain ratings during more anxiety-like states, whereas NSCR correlated to the strength of electrical pain stimulation. That reported pain is moderated by anxiety, puts forward a discussion whether reduction of the anxiety level should be considered during analgesia treatment.

Marital conflict and trajectories of adolescent adjustment: The role of autonomic nervous system coordination

The present study investigates how coordination between stress responsivity of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS) moderates the prospective effects of marital conflict on internalizing and externalizing symptoms across adolescence. Although an important avenue for psychophysiological research concerns how PNS and SNS responses jointly influence adjustment in the context of stress, these processes have rarely been studied in adolescence or longitudinally. Participants were 252 youth (53% female, 66% European American, 34% African American) who participated in laboratory assessments when they were 16, 17, and 18 years old. PNS activity (measured via respiratory sinus arrhythmia [RSA]) and SNS activity (measured via skin conductance level [SCL]) were assessed during a resting baseline and in response to a laboratory-based challenge (star tracing). Parents and adolescents both reported on marital conflict and adolescents reported on their internalizing and externalizing symptoms. At higher levels of marital conflict, coactivation of PNS and SNS activity, characterized by increased RSA and increased SCL from baseline to challenge, predicted elevated internalizing symptoms and an increase in externalizing behavior across adolescence. Coinhibition, or decreased activity across both systems, also predicted an increase in internalizing symptoms over time. At lower levels of marital conflict, internalizing and externalizing symptoms were relatively low. Findings extend primarily cross-sectional work with younger children by demonstrating that coordination between the two branches of the autonomic nervous system (ANS) moderates the longitudinal effects of marital conflict on psychological and behavioral maladjustment among adolescents. (PsycINFO Database Record

Effects of 25 mg oxazepam on emotional mimicry and empathy for pain: a randomized controlled experiment

Emotional mimicry and empathy are mechanisms underlying social interaction. Benzodiazepines have been proposed to inhibit empathy and promote antisocial behaviour. First, we aimed to investigate the effects of oxazepam on emotional mimicry and empathy for pain, and second, we aimed to investigate the association of personality traits to emotional mimicry and empathy. Participants (n=76) were randomized to 25 mg oxazepam or placebo. Emotional mimicry was examined using video clips with emotional expressions. Empathy was investigated by pain stimulating the participant and a confederate. We recorded self-rated experience, activity in major zygomatic and superciliary corrugator muscles, skin conductance, and heart rate. In the mimicry experiment, oxazepam inhibited corrugator activity. In the empathy experiment, oxazepam caused increased self-rated unpleasantness and skin conductance. However, oxazepam specifically inhibited neither emotional mimicry nor empathy for pain. Responses in both experiments were associated with self-rated empathic, psychopathic and alexithymic traits. The present results do not support a specific effect of 25 mg oxazepam on emotional mimicry or empathy.

Effects of 25 mg oxazepam on emotional mimicry and empathy for pain: a randomized controlled experiment

Emotional mimicry and empathy are mechanisms underlying social interaction. Benzodiazepines have been proposed to inhibit empathy and promote antisocial behaviour. First, we aimed to investigate the effects of oxazepam on emotional mimicry and empathy for pain, and second, we aimed to investigate the association of personality traits to emotional mimicry and empathy. Participants (n=76) were randomized to 25 mg oxazepam or placebo. Emotional mimicry was examined using video clips with emotional expressions. Empathy was investigated by pain stimulating the participant and a confederate. We recorded self-rated experience, activity in major zygomatic and superciliary corrugator muscles, skin conductance, and heart rate. In the mimicry experiment, oxazepam inhibited corrugator activity. In the empathy experiment, oxazepam caused increased self-rated unpleasantness and skin conductance. However, oxazepam specifically inhibited neither emotional mimicry nor empathy for pain. Responses in both experiments were associated with self-rated empathic, psychopathic and alexithymic traits. The present results do not support a specific effect of 25 mg oxazepam on emotional mimicry or empathy.

Skin conductance as a pain assessment tool during chest tube removal: An observational study

BACKGROUND

Skin conductance variability to assess pain has shown varying results. Skin conductance responses per second (SCR) during a standardized painful stimulus in awake adults may give further understanding of the method's validity. The purpose of this study was to validate the SCR with the visual analogue scale (VAS) for pain (P-VAS) and anxiety (A-VAS) during chest tube removal (CTR).

METHODS

Ninety-five patients receiving epidural or non-epidural treatment, scheduled for CTR, were studied. Pain or anxiety was considered when VAS > 30 mm; the SCR cut-off value reflecting pain was ≥0.2 SCR.

RESULTS

SCR values could not be recorded in eight cases before CTR, six cases during CTR and seven cases after CTR. CTR induced increases in SCR, P-VAS and A-VAS (p < 0.001). Seventy-seven percent of all pairs of P-VAS and SCR values were well-classified; P-VAS ≤ 30 mm and SCR < 0.2 or P-VAS > 30 mm and SCR ≥ 0.2. SCR obtained before CTR differentiates between patients with and without pain during CTR in all patients (p = 0.04) and in the subgroup of non-anxious patients (p = 0.02), but not in the subgroup of anxious patients. SCR obtained during CTR had similar values in patients with and without pain in all patients and in the subgroup of anxious patients, but in the subgroup of non-anxious patients SCR during CTR differentiates patients with and without pain (p = 0.009).

CONCLUSIONS

SCR increases during painful procedures. Preprocedural SCR may help predict reported pain in patients exposed to painful procedures. SCR during CTR differentiates between patients with and without pain only in non-anxious patients.

SIGNIFICANCE

Preprocedural SCR may help predict reported pain in patients exposed to painful procedures. Procedural SCR accuracy improves in a subgroup of non-anxious patients. P-VAS is influenced by anxiety different from SCR.

Emotional reactivity to incentive downshift as a correlated response to selection of high and low alcohol preferring mice and an influencing factor on ethanol intake

Losing a job or significant other are examples of incentive loss that result in negative emotional reactions. The occurrence of negative life events is associated with increased drinking (Keyes, Hatzenbuehler, & Hasin, 2011). Further, certain genotypes are more likely to drink alcohol in response to stressful negative life events (Blomeyer et al., 2008; Covault et al., 2007). Shared genetic factors may contribute to alcohol drinking and emotional reactivity, but this relationship is not currently well understood. We used an incentive downshift paradigm to address whether emotional reactivity is elevated in mice predisposed to drink alcohol. We also investigated if ethanol drinking is influenced in High Alcohol Preferring mice that had been exposed to an incentive downshift. Incentive downshift procedures have been widely utilized to model emotional reactivity, and involve shifting a high reward group to a low reward and comparing the shifted group to a consistently rewarded control group. Here, we show that replicate lines of selectively bred High Alcohol Preferring mice exhibited larger successive negative contrast effects than their corresponding replicate Low Alcohol Preferring lines, providing strong evidence for a genetic association between alcohol drinking and susceptibility to the emotional effects of negative contrast. These mice can be used to study the shared neurological and genetic underpinnings of emotional reactivity and alcohol preference. Unexpectedly, an incentive downshift suppressed ethanol drinking immediately following an incentive downshift. This could be due to a specific effect of negative contrast on ethanol consumption or a suppressive effect on consummatory behavior in general. These data suggest that either alcohol intake does not provide the anticipated negative reinforcement, or that a single test was insufficient for animals to learn to drink following incentive downshift. However, the emotional intensity following incentive downshift provides initial evidence that this type of emotional reactivity may be a predisposing factor in alcoholism.

'What is more familiar than I? Self, other and familiarity in schizophrenia

BACKGROUND

Familiarity disorders (FDs) critically impact social cognition in persons with schizophrenia. FDs can affect both relationships with people familiar to the patient and the patient's relationship with himself, in the case of a self-disorder. Skin conductance response (SCR) studies have shown that familiar and unknown faces elicit the same emotional response in persons with schizophrenia with FD. Moreover, in control subjects, one's own face and familiar faces have been shown to activate strongly overlapping neural networks, suggesting common processing. The aim of the present study was to determine whether the mechanisms involved in processing one's own and familiar faces are similarly impaired in persons with schizophrenia, suggesting a link between them.

METHOD

Twenty-eight persons with schizophrenia were compared with twenty control subjects. Three face conditions were used: specific familiar, self and unknown. The task was to indicate the gender of the faces presented randomly on a screen during SCR recording. Face recognition was evaluated afterwards.

RESULTS

Control subjects exhibited similar SCRs for the familiar and self-conditions, which were higher than the responses elicited by the unknown condition, whereas persons with schizophrenia exhibited no significant differences between the three conditions.

CONCLUSION

Persons with schizophrenia have a core defect of both self and familiarity that is emphasised by the lack of an increased SCR upon presentation with either self or familiar stimuli. Familiarity with specific familiar faces and one's own face may be driven by the same mechanism. This perturbation may predispose persons with schizophrenia to delusions and, in particular, to general familiarity disorder.

Family conflict, autonomic nervous system functioning, and child adaptation: state of the science and future directions

The family is one of the primary contexts of child development. Marital and parent-child conflict (family conflict) are common and predict a wide range of negative behavioral and emotional outcomes in children. Thus, an important task for developmental researchers is to identify the processes through which family conflict contributes to children's psychological maladjustment, as well as vulnerability and protective factors in the context of family conflict. In the current paper, we aim to advance a conceptual model that focuses on indices of children's autonomic nervous system (ANS) functioning that increase vulnerability or provide protection against psychological maladjustment in the context of family conflict. In doing so, we provide a selective review that reflects the state of the science linking family conflict, children's ANS activity, and child psychological adjustment, and offer directions and guidance for future research. Our hope is to accelerate research at the intersection of family conflict and ANS functioning to advance understanding of risk and resilience among children.

Psychophysiological responses to robot training in different recovery phases after stroke

Psychophysiological responses have become a valuable tool in human-robot interaction since they provide an objective estimate of the user's psychological state. Unfortunately, their usefulness in rehabilitation robotics is uncertain since they are influenced by both physical activity and pathological conditions such as stroke. We performed psychophysiological measurements in subacute and chronic stroke patients as well as healthy controls during a reaching and grasping exercise task performed in a multimodal virtual environment. Furthermore, we evaluated the differences in kinematic and static parameters between the three groups of subjects. The results of the observed kinematic and static evaluation parameters showed significant differences when different assistive modes enabled the subject to focus on a particular function of the exercise, like reaching or grasping, or coordinated actions that combine reaching and grasping, reflecting the motor abilities of the individual. The analysis of psychophysiological responses suggests that both chronic and subacute stroke subjects have weaker psychophysiological responses than healthy subjects, though the responses of chronic patients have recovered somewhat. This certainly indicates that further studies are needed before psychophysiological responses can be used in clinical practice.

Attenuated subjective ratings and skin conductance responses to neutral and negative pictures in non-psychopathic mentally disordered offenders with various diagnoses

Altered autonomic arousal in relation to offending behavior has mainly been investigated in subjects with varying degrees of psychopathic traits. The present study sets out to investigate subjective ratings and skin conductance responses (SCRs) in mentally disordered offenders with various diagnoses but without psychopathy, specifically recruited from the forensic psychiatric system. Two subgroups were investigated; an antisocial group with antisocial personality disorder (APD) or antisocial traits (n=16) and a non-antisocial group with various diagnoses (n=25), in relation to a healthy non-criminal control group (n=20). All participants were male. SCRs and subjective ratings of arousal and valence were measured for neutral and negative pictures from the International Affective Picture System (IAPS). The offenders showed significantly lower SCRs and subjective ratings than the control group. Moreover, there was no significant difference between antisocial and non-antisocial offenders, indicating that antisocial behavior might not be a differential factor. Thus, attenuated emotional responses may be a characteristic shared by mentally disordered offenders overall.

Psychophysiological responses to robotic rehabilitation tasks in stroke

This paper presents the analysis of four psychophysiological responses in post-stroke upper extremity rehabilitation. The goal was to determine which psychophysiological responses would provide the most reliable information about subjects' psychological states during rehabilitation. Heart rate, skin conductance, respiration, and skin temperature were recorded in a stroke group and a control group during two difficulty levels of a pick-and-place task performed in a virtual environment using a haptic robot and during a cognitive task. Psychophysiological measurements were correlated with results of a self-report questionnaire. All four responses showed significant changes in response to the different tasks. Skin conductance differentiated between the two difficulty levels and was correlated with self-reported arousal in both stroke and control groups. Skin temperature differentiated between the two difficulty levels for the control group, but provided poor results for the stroke group. Heart rate and respiration increased during tasks, but their connection to psychological state was unclear. Results suggest that, of the four measured responses, skin conductance offers the most potential as a psychological state indicator, with other measures providing supplementary information. Psychophysiological measurements could thus be used in closed-loop biocooperative systems that would detect the user's psychological state and change the course of therapy accordingly.