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- Mayo, Leah M., 1987-, et al.
(author)
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Gender differences in the behavioral and subjective effects of methamphetamine in healthy humans
- 2019
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In: Psychopharmacology. - : Springer. - 0033-3158 .- 1432-2072. ; 236:8, s. 2413-2423
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Journal article (peer-reviewed)abstract
- RationaleMethamphetamine (MA) use is steadily increasing and thus constitutes a major public health concern. Women seem to be particularly vulnerable to developing MA use disorder, as they initiate use at a younger age and transition more quickly to problematic use. Initial drug responses may predict subsequent use, but little information exists on potential gender differences in the acute effects of MA prior to dependence.ObjectiveWe examined gender differences in the acute effects of MA on subjective mood and reward-related behavior in healthy, non-dependent humans.MethodsMen (n = 44) and women (n = 29) completed 4 sessions in which they received placebo or MA under double-blind conditions twice each. During peak drug effect, participants completed the monetary incentive delay task to assess reaction times to cues signaling potential monetary losses or gains, in an effort to determine if MA would potentiate reward-motivated behavior. Cardiovascular and subjective drug effects were assessed throughout sessions.ResultsOverall, participants responded more quickly to cues predicting incentivized trials, particularly large-magnitude incentives, than to cues predicting no incentive. MA produced faster reaction times in women, but not in men. MA produced typical stimulant-like subjective and cardiovascular effects in all participants, but subjective ratings of vigor and (reduced) sedation were greater in women than in men.ConclusionsWomen appear to be more sensitive to the psychomotor-related behavioral and subjective effects of MA. These findings provide initial insight into gender differences in acute effects of MA that may contribute to gender differences in problematic MA use.
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| 2. |
- Perini, Irene, et al.
(author)
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Brain-based Classification of Negative Social Bias in Adolescents With Nonsuicidal Self-injury : Findings From Simulated Online Social Interaction.
- 2019
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In: eClinicalMedicine. - : Elsevier. - 2589-5370. ; 13, s. 81-90
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Journal article (peer-reviewed)abstract
- Background: Interpersonal stress and perceived rejection have been clinically observed as common triggers of nonsuicidal self-injury (NSSI), with self-injury behavior regulating both affective and social experiences. We investigated whether the subjective interpretation of social interaction in a simulated online environment might be biased in the NSSI group, and the brain mechanisms underlying the experience.Methods: Thirty female adolescent patients with NSSI and thirty female age-matched controls were investigated in this case-control study. In our novel task that simulates interaction on current social media platforms, participants indicated whether they liked or disliked pictures of other players during a functional magnetic resonance imaging (fMRI) scan. Participants also viewed positive and negative feedback directed toward them by others. The task also assessed the subjective effects of the social interaction. Finally, subjects underwent a separate facial electromyography session, which measured facial expressions processing.Outcomes: Behaviorally, the NSSI group showed a negative bias in processing social feedback from others. A multi-voxel pattern analysis (MVPA) identified brain regions that robustly classified NSSI subjects and controls. Regions in which mutual activity contributed to the classification included dorsomedial prefrontal cortex and subgenual anterior cingulate cortex, a region implicated in mood control. In the NSSI group, multi-voxel classification scores correlated with behavioral sensitivity to negative feedback from others. Results remained significant after controlling for medication, symptoms of depression, and symptoms of borderline personality disorder.Interpretation: This study identified behavioral and neural signatures of adolescents with NSSI during social interaction in a simulated social media environment. These findings highlight the importance of understanding social information processing in this clinical population and can potentially advance treatment approaches.
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