Background Anhedonia is a core symptom of major depressive disorder (MDD) and may persist despite otherwise effective treatment. Electroconvulsive therapy (ECT) is a widely used and effective intervention for severe and treatment-resistant depression, however, its specific effects on anhedonia remain poorly characterized. Objective To conduct a systematic review and meta-analysis examining ECT-associated changes in anhedonia in adults with MDD. Methods A systematic search was conducted across Embase, MEDLINE, PsycINFO, and Scopus. Studies were eligible if they included adults with MDD, administered ECT as a treatment, and assessed anhedonia using a validated scale. Standardized mean change ratios (SMCs) were calculated and pooled using a random-effects model. Results Eleven studies were included in the systematic review, of which five provided quantitative data for meta-analysis. Across 132 participants, ECT was associated with a significant improvement in anhedonia severity (SMC = 1.02; 95% CI, 0.63–1.42). Conclusions ECT was associated with a statistically significant improvement in anhedonia among adults with MDD. However, given the small number of included studies and non-randomized pre-post designs, these findings should be interpreted cautiously. Future ECT studies should assess anhedonia as an outcome, while using a validated anhedonia measure.
Adolescent females are at increased risk for mental health problems, and differences in pubertal hormone dynamics may help explain this vulnerability. During puberty, oestradiol (E2) and progesterone (P4) fluctuate substantially as endocrine patterns stabilise, yet little is known about how hormone variability relates to brain structure and emotional functioning during adolescence. We investigated within-individual variability in E2 and P4, measured weekly, and its relation to brain structure and mental health.Participants were 145 females (11–17 years) from the Puberty and NeuroDevelopment in Adolescents (PANDA) study in Australia. Salivary E2 and P4 were collected weekly for five weeks, with variability indexed as within-subject standard deviation. Structural MRI was acquired on the final sampling day. Mental health, including anxiety, depressive symptoms, and emotional dysregulation, was assessed using self- and parent-report measures. Linear regression and mediation analyses tested associations between hormone variability, brain structure, and mental health.Greater P4 variability was associated with smaller left thalamus volume (Cohen's d = −0.26, pFDR = 0.031). After removing an influential observation using Cook's distance, higher E2 variability was associated with fewer anxiety (d = −0.170, pFDR = 0.043) and depressive symptoms (d = −0.179, pFDR = 0.036), lower emotion dysregulation (d = −0.179, pFDR = 0.036), and smaller right hippocampus volume, particularly among premenarchal adolescents compared to postmenarchal adolescents (d = −0.192, p = 0.02).These findings indicate that hormone variability may shape brain and affective functioning in adolescent girls differently from hormone-related transitions in adulthood. Larger, replicable, and longer-term studies are needed to confirm these patterns.
Unpredictable threats can sustain vigilance states that bias perception, cognition, and behaviour beyond immediate stimulus processing. Human screams, as evolutionarily salient alarm signals, are especially effective in eliciting defensive responses, yet their cortical dynamics and consequences for subsequent social regulation remain poorly understood. Using functional near-infrared spectroscopy (fNIRS), we dissociated anticipatory and stimulus-evoked cortical responses during exposure to either unpredictable human screams or laughter, and examined whether these effects generalize to interpersonal behaviour. Seventy-one participants completed two auditory blocks (Threat: screams; Safe: laughter) while prefrontal and temporal cortical activity was recorded, followed by a virtual interpersonal task measuring preferred distance and perceived discomfort. Unpredictable screams increased anxiety and elicited sustained anticipatory activation in the left temporal cortex, together with phasic responses in bilateral dorsolateral prefrontal and posterior temporal regions. In contrast, laughter induced more limited fronto-central activation and no anticipatory effects. Behaviourally, threat exposure was associated with earlier stopping of the approaching avatar, consistent with greater preferred interpersonal distance and defensive distancing. Discomfort during the interpersonal assessment was also elevated, particularly when the threat condition was presented first, suggesting a possible influence of session order or familiarization. Finally, exploratory analyses suggested that catastrophizing and perceived stress contributed to variability in neural and behavioural responses. Together, these findings indicate that unpredictable auditory threat induces sustained cortical vigilance that extends into subsequent social interaction, shifting interpersonal regulation toward defensive distancing.
