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

Negative emotionality downregulation affects moral choice but not moral judgement of harm: a pharmacological study

Previous neuroscientific research has expounded on the fundamental role played by emotion during moral decision-making. Negative emotionality has been observed to exert a general inhibitory effect towards harmful behaviors against others. Nevertheless, the downregulation of negative affects at different levels of moral processing (e.g. impersonal versus personal moral dilemmas) alongside its possible interactions with other factors (e.g. perspective taking) hasn't been directly assessed; both of which can assist in predicting future moral decision-making. In the present research, we empirically test (Study 1, N = 41) whether downregulating negative emotionality through pharmacological interventions using lorazepam (a GABA receptor agonist), modulate the permissibility of harm to others -i.e. if participants find it more morally permissible to harm others when harm is unavoidable (inevitable harm moral dilemmas), than when it may be avoided (evitable harm moral dilemmas). Furthermore, using another sample (Study 2, N = 31), we assess whether lorazepam's effect is modulated by different perspective-taking conditions during a moral dilemma task -e.g. "is it morally permissible for you to […]?" (1st person perspective), relative to "is it morally permissible for [x individual] to […]?" (3rd person perspective)-, where the outcome of the different scenarios is controlled. The results of both studies converge, revealing an emotion-dependent, rather than an outcome-dependent, pharmacological modulation. Lorazepam only influenced interpersonal moral judgments when not modulated by the evitable/inevitable condition. Furthermore, there was a significant interaction between perspective-taking and drug administration, as lorazepam exerted a larger effect in modulating moral choices rather than moral judgements.

A systematic review of the effects of psychiatric medications on social cognition

INTRODUCTION

Social cognition is an important area of mental functioning relevant to psychiatric disorders and social functioning, that may be affected by psychiatric drug treatments. The aim of this review was to investigate the effects of medications with sedative properties, on social cognition.

METHOD

This systematic review included experimental and neuroimaging studies investigating drug effects on social cognition. Data quality was assessed using a modified Downs and Black checklist (Trac et al. CMAJ 188: E120-E129, 2016). The review used narrative synthesis to analyse the data.

RESULTS

40 papers were identified for inclusion, 11 papers investigating benzodiazepine effects, and 29 investigating antipsychotic effects, on social cognition. Narrative synthesis showed that diazepam impairs healthy volunteer's emotion recognition, with supporting neuroimaging studies showing benzodiazepines attenuate amygdala activity. Studies of antipsychotic effects on social cognition gave variable results. However, many of these studies were in patients already taking medication, and potential practice effects were identified due to short-term follow-ups.

CONCLUSION

Healthy volunteer studies suggest that diazepam reduces emotional processing ability. The effects of benzodiazepines on other aspects of social cognition, as well as the effects of antipsychotics, remain unclear. Interpretations of the papers in this review were limited by variability in measures, small sample sizes, and lack of randomisation. More robust studies are necessary to evaluate the impact of these medications on social cognition.

Oxazepam and cognitive reappraisal: A randomised experiment

Background

Cognitive reappraisal is a strategy for emotional regulation, important in the context of anxiety disorders. It is not known whether anxiolytic effects of benzodiazepines affect cognitive reappraisal.

Aims

We aimed to investigate the effect of 25 mg oxazepam on cognitive reappraisal.

Methods

In a preliminary investigation, 33 healthy male volunteers were randomised to oxazepam or placebo, and then underwent an experiment where they were asked to use cognitive reappraisal to upregulate or downregulate their emotional response to images with negative or neutral emotional valence. We recorded unpleasantness ratings, skin conductance, superciliary corrugator muscle activity, and heart rate. Participants completed rating scales measuring empathy (Interpersonal Reactivity Index, IRI), anxiety (State-Trait Anxiety Inventory, STAI), alexithymia (Toronto Alexithymia Scale-20, TAS-20), and psychopathy (Psychopathy Personality Inventory-Revised, PPI-R).

Results

Upregulation to negative-valence images in the cognitive reappraisal task caused increased unpleasantness ratings, corrugator activity, and heart rate compared to downregulation. Upregulation to both negative- and neutral-valence images caused increased skin conductance responses. Oxazepam caused lower unpleasantness ratings to negative-valence stimuli, but did not interact with reappraisal instruction on any outcome. Self-rated trait empathy was associated with stronger responses to negative-valence stimuli, whereas self-rated psychopathic traits were associated with weaker responses to negative-valence stimuli.

Conclusions

While 25 mg oxazepam caused lower unpleasantness ratings in response to negative-valence images, we did not observe an effect of 25 mg oxazepam on cognitive reappraisal.

Association between homicide injury severity and benzodiazepine influence

There are case reports of offenders inflicting excessive injuries on their victims when under the influence of benzodiazepines. However, the potential association between benzodiazepine influence on the offender and victim injury severity in a general homicide population has not been studied. We investigated associations between offender positive testing for benzodiazepines or z-drugs (zolpidem, zopiclone and zaleplon) and victim injury severity. Data were drawn from 95 Swedish homicide cases from 2007–2009 in which offenders had known toxicology. There were no significant differences in injury severity between cases in which the offender tested positive vs. negative for benzodiazepines/z-drugs. Thus, the findings do not support the hypothesis that there is an association between benzodiazepine influence on the offender and victim injury severity in a general homicide population.

Key points

Some previous studies have linked benzodiazepines to aggression, violence and excessive homicide injuries.

The present study analysed the association between homicide injury severity and benzodiazepine status of the offender.

Offenders who tested positive for benzodiazepines did not inflict more severe injuries on their victims.

These findings do not support the hypothesis that benzodiazepine influence generally causes offenders to inflict more severe injuries on homicide victims.

Recognition of emotional facial expressions in benzodiazepine dependence and detoxification

INTRODUCTION

The study investigates how benzodiazepine (BZD) use and detoxification affects empathy and the recognition and intensity rating of emotional facial expressions. The sample comprised 43 participants in three groups: (1) during detoxification (N = 13), (2) after detoxification (N = 15), (3) a matched control group (N = 15). Clinical subjects were recruited from in-patients of an addiction treatment unit.

METHODS

Empathy levels were tested with the Empathy Quotient (EQ-Short). Recognition accuracy and emotion intensity rating were based on a computerised task displaying static and dynamic facial expressions of joy, anger, sadness, and fear.

RESULTS

The controls proved more accurate than both experimental groups in identifying facial expressions of negative emotions. Joy recognition proved most accurate overall. Among the clinical subjects, women in particular exhibited an impaired ability to correctly identify negative emotions from facial expressions. Dynamic stimuli were better recognised than static ones albeit only in the experimental groups. No significant differences were found for emotion intensity ratings and EQ scores.

CONCLUSION

Our findings suggest that the impaired facial emotion recognition accuracy is not caused by deficits in empathy. No improvement was recorded post-detoxification which may indicate impaired interpersonal functioning among BZD users. Further research is warranted in light of this study's limitations.