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Background: Depression is characterized by disturbed emotion processing, with aberrant neural and physiological responses to emotional stimuli. Here, we applied an emotion anticipation and processing paradigm to investigate brain neural and electrodermal reactivities in patients with depression compared with healthy controls.

Methods: The study included 42 patients (27 females) and 44 healthy controls (21 females). Subjects underwent functional magnetic resonance imaging with simultaneous measurement of electrodermal activity. During scanning, red or green color cues were presented, followed by pictures of negative or positive valence, respectively. Behavioral valence and arousal ratings of the picture stimuli were conducted after scanning. Anhedonia was assessed through a semi-structured interview in both subject groups.

Results: Patients perceived positive pictures as less positive than controls did. Positive anticipation (i.e., green color cues) elicited stronger activations in the anterior cingulate cortex and the right insula in patients than in healthy controls, indicating salience network disturbances. An exploratory analysis of all regions in the Automated Anatomical Labeling Atlas 2 found significant differences in activity to positive anticipation between groups in several brain regions involved in cognition and emotion processing. Positive and negative anticipation elicited stronger electrodermal responses in healthy controls. However, electrodermal reactivity to negative pictures was higher in patients than in controls.

Conclusions: Ongoing depression affects emotion anticipation and processing at the behavioral, neural, and physiological levels. These findings contribute to increased understanding of the disorder.

Past results suggest that fear extinction and the return of extinguished fear are compromised in adolescents. However, findings have been inconclusive as there is a lack of fear extinction and extinction retention studies including children, adolescents and adults. In the present study, 36 children (6-9 years), 40 adolescents (13-17 years) and 44 adults (30-40 years), underwent a two-day fear conditioning task. Habituation, acquisition, and extinction were performed on the first day and an extinction retention test > 24 h later. Skin conductance responses were recorded during all phases of fear conditioning and functional magnetic resonance imaging (fMRI) was conducted during the fear retention test. All groups acquired and extinguished fear as measured with SCR, with no group differences in SCR during extinction retention. The groups had largely similar neural fear responses during the retention test, apart from adolescents displaying stronger amygdala fear response than children, with no differences between adolescents and adults. The findings do not support an adolescent extinction dip, and there was only marginal evidence of progressive changes in fear conditioning across development. In contrast to findings in rodents, fear conditioning in humans may elicit similar physiological responses and recruit similar neural networks from childhood to adulthood.

Background: The Swedish Universities Scales of Personality (SSP) is a personality measurement tool with a short test battery of high psychometric quality, previously not availiable in Japanese.

Methods: We translated the SSP into Japanese and administered it to 103 Japanese nationals. For 11 of the 13 SSP scales in the Japanese version of the SSP (SSP-J11), the Cronbach’s alpha ranged from 0.50 to 0.82 with good internal scale reliability.

Results: A principal factor analysis replicated the previous work by identifying the same three principal dimensions of Neuroticism, Aggression, and Extraversion factors.

Conclusion: The resulting three-factor SSP-J11 shows acceptable reliability and should provide informative insights about personality traits in research and clinical practice in a Japanese context.

Background

Electroconvulsive therapy (ECT) is an important treatment for several severe psychiatric conditions, yet its precise mechanism of action remains unknown. Increased inhibition in the brain after ECT seizures, mediated by γ-aminobutyric acid (GABA), has been linked to clinical effectiveness. Case series on epileptic patients report a postictal serum concentration increase of the GABA_A receptor agonist allopregnanolone. Serum allopregnanolone remains unchanged after a full ECT series, but possible transient effects directly after a single ECT seizure remain unexplored. The primary aim was to measure serum concentrations of allopregnanolone and its substrate progesterone after one ECT seizure. Secondary aims were to examine whether concentrations at baseline, or postictal changes, either correlate with seizure generalization or predict clinical outcome ratings after ECT.

Methods

A total of 130 participants (18–85 years) were included. Generalization parameters comprised peak ictal heart rate, electroencephalographic (EEG) seizure duration, and prolactin increase. Outcome measures were ratings of clinical global improvement, perceived health status and subjective memory impairment. Non-parametric tests were used for group comparisons and correlations. The prediction analyses were conducted with binary logistic and simple linear regression analyses.

Results

Allopregnanolone and progesterone remained unchanged and correlated neither with seizure generalization nor with clinical outcome. In men (n = 50), progesterone increased and allopregnanolone change correlated negatively with EEG seizure duration. In a subgroup analysis (n = 62), higher baseline allopregnanolone and progesterone correlated with postictal EEG suppression.

Conclusions

ECT seizures have different physiologic effects than generalized seizures in epilepsy. Progesterone might have implications for psychiatric illness in men.

Social activities are likely to cause effects or reactivity in the brains of the people involved in collaborative social situations. This study assesses a new method, Tigramite, for time domain analysis of directed causality between the prefrontal cortex (PFC) of persons in such situations. An experimental situation using hyperscanning EEG was applied while individuals led and followed each other in finger-tapping rhythms. This structured task has a long duration and a high likelihood of inter-brain causal reactions in the prefrontal cortices. Tigramite is a graph-based causal discovery method to identify directed causal relationships in observational time series. Tigramite was used to analyze directed causal connections within and between the PFC. Significantly directed causality within and between brains could be detected during the social interactions. This is the first empirical evidence the Tigramite can reveal inter- and intra-brain-directed causal effects in hyperscanning EEG time series. The findings are promising for further studies of causality in neural networks during social activities using Tigramite on EEG in the time domain.

During adolescence, emotion regulation and reactivity are still developing and are in many ways qualitatively different from adulthood. However, the neurobiological processes underpinning these differences remain poorly understood, including the role of maturing neurotransmitter systems. We combined magnetic resonance spectroscopy in the dorsal anterior cingulate cortex (dACC) and self-reported emotion regulation and reactivity in a sample of typically developed adolescents (n = 37; 13-16 years) and adults (n = 39; 30-40 years), and found that adolescents had higher levels of glutamate to total creatine (tCr) ratio in the dACC than adults. A glutamate i age group interaction indicated a differential relation between dACC glutamate levels and emotion regulation in adolescents and adults, and within-group follow-up analyses showed that higher levels of glutamate/tCr were related to worse emotion regulation skills in adolescents. We found no age-group differences in gamma-aminobutyric acid+macromolecules (GABA+) levels; however, emotion reactivity was positively related to GABA+/tCr in the adult group, but not in the adolescent group. The results demonstrate that there are developmental changes in the concentration of glutamate, but not GABA+, within the dACC from adolescence to adulthood, in accordance with previous findings indicating earlier maturation of the GABA-ergic than the glutamatergic system. Functionally, glutamate and GABA+ are positively related to emotion regulation and reactivity, respectively, in the mature brain. In the adolescent brain, however, glutamate is negatively related to emotion regulation, and GABA+ is not related to emotion reactivity. The findings are consistent with synaptic pruning of glutamatergic synapses from adolescence to adulthood and highlight the importance of brain maturational processes underlying age-related differences in emotion processing.

Background: The antidepressant effect of repetitive transcranial magnetic stimulation (rTMS) is partly placebo, making blinding integrity important. Blinding of high-frequency rTMS and intermittent theta burst stimulation (iTBS) has been reported as successful at study end. However, blinding integrity at study start is rarely reported. The aim of this study was to investigate blinding integrity during a treatment course of iTBS over the dorsomedial prefrontal cortex (DMPFC) in depression.

Methods: Forty-nine patients with depression from a double-blind-designed randomized controlled trial (NCT02905604) were included. Patients received either active or sham iTBS over the DMPFC with a placebo coil. The sham group received iTBS-synchronized transcutaneous electrical nerve stimulation.

Results: After one session, 74% of participants were able to correctly guess their treatment allocation. This was above chance level (p = 0.001). The percentage dropped to 64% and 56% after the fifth and last sessions. Belong-ing to the active group influenced the choice to guess "active" (odds ratio: 11.7, 95% CI 2.5-53.7). A higher treat-ment intensity of the sham treatment increased the probability to guess "active", but pain did not influence the choice.

Conclusions: Blinding integrity in iTBS trials must be investigated at study start to avoid uncontrolled confounding. Better sham methods are needed.

Background: Social anxiety disorder (SAD) is associated with aberrant emotional information processing while little is known about non-emotional cognitive processing biases. The dorsal anterior cingulate cortex (dACC) has been implicated in SAD neuropathology and is activated both by emotional and non-affective cognitive challenges like the Multisource Interference Task (MSIT).

Methods: Here, we used fMRI to compare dACC activity and test performance during MSIT in 69 SAD patients and 38 healthy controls. In addition to patient-control comparisons, we examined whether neural activity in the dACC correlated with social anxiety, trait anxiety or depression levels.

Results: The MSIT activated the dACC as expected but with no differences in task performance or neural reactivity between SAD patients and controls. There were no significant correlations between dACC activity and social or trait anxiety symptom severity. In patients, there was a significant negative correlation between dACC activity and depressive symptoms.

Conclusions: In absence of affective challenge, we found no disorder-related cognitive profile in SAD patients since neither MSIT task performance nor dACC neural activity deviated in patients relative to controls.

Objective Physiological parameters that predict electroconvulsive therapy (ECT) effectiveness may reflect propagation of the induced epileptic seizure. As an indication of seizure propagation to the diencephalon, we here examined the correlation between prolactin increase after ECT and clinical seizure evaluation parameters, focusing on peak heart rate. As a proxy for peripheral endocrine stress response, we examined the correlation to postictal cortisol increase. Methods Participants were consecutively recruited from clinical ECT patients (n = 131, age 18-85 years). The first ECT session in a series was examined. For each participant, blood serum concentrations of prolactin and cortisol were measured immediately before and within 30 min after the seizure. Physiological parameters were extracted from clinical records: peak heart rate (HR) during seizure, electroencephalography (EEG) seizure duration, and motor seizure duration. Correlations were calculated using non-parametric tests. Results Serum prolactin increased after ECT and correlated with peak HR, EEG seizure duration, and motor seizure duration. Peak HR during seizure also correlated positively with both EEG seizure duration and motor seizure duration. Correlations were unaffected by age, sex, baseline prolactin levels, antipsychotics, or beta-blocking agents. Serum cortisol increased after ECT but did not correlate with the seizure evaluation parameters, nor with prolactin concentrations. Conclusions Our findings of a positive correlation between peak HR and prolactin that was independent from the peripheral endocrine stress response might be in line with the idea that tachycardia during ECT seizures reflects seizure propagation to the diencephalon. This supports the practice of monitoring cardiovascular response for ECT seizure evaluation.

Depressive symptoms are associated with altered pupillary responses during learning and reward prediction as well as with changes in neurometabolite levels, including brain concentrations of choline, glutamate and gamma-aminobutyric acid (GABA). However, the full link between depressive symptoms, reward-learning-related pupillary responses and neurometabolites is yet to be established as these constructs have not been assessed in the same individuals. The present pilot study, investigated these relations in a sample of 24 adolescents aged 13 years. Participants completed the Revised Child Anxiety and Depression Scale (RCADS) and underwent a reward learning task while measuring pupil dilation and a single voxel dorsal anterior cingulate cortex (dACC) MEGA-PRESS magnetic resonance spectroscopy scan assessing choline, glutamate and GABA concentrations. Pupil dilation was related to prediction errors (PE) during learning, which was captured by a prediction error-weighted pupil dilation response index (PE-PDR) for each individual. Higher PE-PDR scores, indicating larger pupil dilations to negative prediction errors, were related to lower depressive symptoms and lower dACC choline concentrations. Dorsal ACC choline was positively associated with depressive symptoms, whereas glutamate and GABA were not related to PE-PDR or depressive symptoms. The findings support notions of cholinergic involvement in depressive symptoms and cholinergic influence on reward-related pupillary response, suggesting that pupillary responses to negative prediction errors may hold promise as a biomarker of depressive states.