Differential neural processing of social exclusion in adolescents with non-suicidal self-injury: An fMRI study

AbstractNon-suicidal self-injury (NSSI) is highly prevalent in adolescence and has been suggested as an autonomous diagnosis in the Diagnostic and Statistical Manual (DSM-5). Social rejection is as potential risk-factor for NSSI and depression in adolescence. Objectives of this study were to identify differences in neural processing of social rejection in depressed adolescents with and without co-morbid NSSI and healthy controls. Participants were 28 depressed adolescents (14 with co-morbid NSSI, 79% females) and 15 healthy controls, with an average age of 15.2 years (SD=1.8). Social exclusion was implemented using the Cyberball paradigm ‘Cyberball’ during functional magnetic resonance imaging (fMRI). All participants reported feelings of social exclusion after fMRI scanning. Investigating the effects of NSSI, we found that depressed adolescents with NSSI showed relatively enhanced activation of the medial prefrontal cortex (mPFC) and the ventrolateral prefrontal cortex (vlPFC) compared to depressed adolescents without NSSI and also compared to healthy controls. Results point towards divergent processing of social exclusion in depressed adolescents with NSSI as compared to adolescents with mere depression in brain regions previously related to the processing of social exclusion. This finding of distinct neurophysiological responses may stimulate further research on individual treatment approaches

Side Effects of Transcranial Magnetic Stimulation Biased Task Performance in a Cognitive Neuroscience Study

Summary:: Transcranial magnetic stimulation (TMS) is increasingly used as a research tool for functional brain mapping in cognitive neuroscience. Despite being mostly tolerable, side effects of TMS could influence task performance in behavioural TMS studies. In order to test this issue, healthy subjects assessed the discomfort caused by the stimulation during a verbal working memory task. We investigated the relation between subjective disturbance and task performance. Subjects were stimulated during the delay period of a delayed-match-to-sample task above cortical areas that had been identified before to be involved in working memory. Task performance and subjective disturbance due to side effects were monitored. The subjects' grade of discomfort correlated with the error rates: the higher the discomfort, the more errors were made. Conclusively, TMS side effects may bias task performance in cognitive neuroscience studies and may thereby lead to misinterpretation of results. We emphasize the importance of controlling side effects of the stimulation as a source of biasing effects in TMS studie

Neural correlates of the perception of dynamic versus static facial expressions of emotion

Aim: This study investigated brain areas involved in the perception of dynamic facial expressions of emotion

Neural Correlates of Social Inclusion in Borderline Personality Disorder

Humans engage in social interactions and have a fundamental need and motivation to establish and maintain social connections. Neuroimaging studies particularly focused on the neural substrates of social exclusion in healthy subjects (HC), borderline personality disorder (BPD), and major depression (MD). However, there is evidence regarding neural alterations also during social inclusion in BPD that we intended to elucidate in our study. Considering that patients with BPD often have comorbid MD, we investigated patients with BPD, and comorbid MD, patients with MD without BPD, and a sample of HC. By investigating these two clinical samples within one study design, we attempted to disentangle potential confounds arising by psychiatric disorder or medication and to relate neural alterations under social inclusion specifically to BPD. We investigated 48 females (15 BPD and MD, 16 MD, and 17 HC) aged between 18 and 40 years by fMRI (3T), using the established cyberball paradigm with social exclusion, inclusion, and passive watching conditions. Significant group-by-condition interaction effects (p < 0.05, FWE-corrected on cluster level) were observed within the dorsolateral (dlPFC) and dorsomedial prefrontal cortex (dmPFC), the temporo-parietal junction (TPJ), the posterior cingulate cortex (PCC), and the precuneus. Comparisons of estimated neural activations revealed that significant interaction effects were related to a relative increase in neural activations during social inclusion in BPD. In detail, we observed a significant increase in differential (social inclusion vs. passive watching) neural activation within the dmPFC and the PCC in BPD compared to both, MD and HC. However, significant interaction effects within the dlPFC and the TPJ could not specifically be linked to BPD considering that they did not differ significantly between the two clinical groups in post-hoc comparisons. Our study supports previous results on effects of social and inclusion in BPD, and provides further evidence regarding disorder specific neural alterations in BPD for brain regions associated with self-referential and mentalizing processes during social inclusion

From uncertainty to reward: BOLD characteristics differentiate signaling pathways

<p>Abstract</p> <p>Background</p> <p>Reward value and uncertainty are represented by dopamine neurons in monkeys by distinct phasic and tonic firing rates. Knowledge about the underlying differential dopaminergic pathways is crucial for a better understanding of dopamine-related processes. Using functional magnetic resonance blood-oxygen level dependent (BOLD) imaging we analyzed brain activation in 15 healthy, male subjects performing a gambling task, upon expectation of potential monetary rewards at different reward values and levels of uncertainty.</p> <p>Results</p> <p>Consistent with previous studies, ventral striatal activation was related to both reward magnitudes and values. Activation in medial and lateral orbitofrontal brain areas was best predicted by reward uncertainty. Moreover, late BOLD responses relative to trial onset were due to expectation of different reward values and likely to represent phasic dopaminergic signaling. Early BOLD responses were due to different levels of reward uncertainty and likely to represent tonic dopaminergic signals.</p> <p>Conclusions</p> <p>We conclude that differential dopaminergic signaling as revealed in animal studies is not only represented locally by involvement of distinct brain regions but also by distinct BOLD signal characteristics.</p

Somatosensory Stimulus Intensity Encoding in Borderline Personality Disorder

Borderline Personality Disorder (BPD) is clinically characterized by emotional instability, interpersonal disturbances and dysfunctional behavior such as non-suicidal self-injury (NSSI). During NSSI, patients with BPD typically report analgesic or hypoalgesic phenomena, and pain perception and pain processing in BPD have been repeatedly investigated. Most of the studies so far focused on affective-motivational and cognitive-evaluative neural components of pain within categorial study designs. By contrast, rather basic somatosensory aspects such as neural intensity-encoding of somatosensory stimuli were not examined in further details. Thus, we investigated patients with BPD and healthy controls (HC) by functional magnetic resonance imaging (fMRI) during an unpleasant sensory stimulation task with parametrically increasing stimulus intensities. 15 females diagnosed with BPD and 15 HCs were investigated with fMRI during four individually adjusted levels of electrical stimulus intensities. Ratings of stimulus intensity were assessed by button presses during fMRI. fMRI-data were analyzed by analyses of variances (ANOVA) at a statistical threshold of p &lt; 0.05 FWE-corrected on cluster level. Subjective ratings of stimulus intensities were alike between BPD and HC, and intensity levels identified with equal accuracy. Significant intensity-encoding neural activations were observed within the primary and secondary somtasensory cortex, the posterior insula, the posterior midcingulate cortex (pMCC) and the supplementary motor area (SMA) in both, HC and BPD. Notably, there were no significant between-groups differences in intensity-encoding neural activations, even at lowered significance thresholds. Present results suggest a similar neural somatosensory stimulus intensity encoding in BPD as previously observed on a behavioral level. The alterations in neural affective-motivational or cognitive-evaluative components reported so far may be restricted to pain rather than unpleasant stimulus processing and were absent in our study

Cortical thickness and resting-state cardiac function across the lifespan: a cross-sectional pooled mega analysis

Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12-87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS – or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between cortical thickness and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research

Untersuchung des Arbeitsgedächtnisses mit funktioneller Magnetresonanztomographie und neuronavigierter transkranieller Magnetstimulation

In der vorliegenden Studie wurden funktionelle Magnetresonanztomographie (fMRT) und transkranielle Magnetstimulation (TMS) im Rahmen einer Arbeitsgedächtnisuntersuchung kombiniert. Gemäß der Hypothese beeinträchtigt TMS über nach fMRT aktiven Gehirnarealen die Gedächtnisfunktion. Mit Hilfe der fMRT wurden bei 8 Probanden individuell Gehirnareale identifiziert, die im Merkintervall bei Durchführung einer modifizierten Sternberg-Aufgabe aktiv waren. Die Stimulation erfolgte anschließend während des Merkintervalls einer vergleichbaren Aufgabe, wobei die TMS-Spule neuronavigiert über den jeweiligen Aktivierungen positioniert wurde. Es wurden eine Kontrollstimulation über der nichtaktiven Gegenseite des Kortex und eine Scheinstimulation ohne Kontakt zur Kopfoberfläche durchgeführt. Die Probanden wurden mit einem kurzen Fragebogen zur subjektiven Beeinträchtigung durch die Stimulation befragt. Gemäß fMRT fanden sich Aktivierungen insbesondere im linken präfrontalen, prämotorischen und parietalen Kortex. Bei Stimulation der individuellen prämotorischen Aktivierungen wurden signifikant höhere Fehlerraten im Vergleich zur Kontrollbedingung festgestellt, nicht aber bei präfrontaler und parietaler TMS. Gegenüber der schmerzfreien Scheinstimulation wurden signifikant erhöhte Fehlerraten in der präfrontalen TMS-Bedingung gemessen. Die Auswertung der Fragebögen ergab, dass sich die Probanden besonders bei präfrontaler TMS durch den Schmerzreiz bei der Stimulation beeinträchtigt fühlten. Hohe durchschnittliche Fehlerraten waren hier korreliert mit hoher subjektiver Schmerzempfindung. Die Beeinträchtigung des Arbeitsgedächtnisses bei prämotorischer Stimulation kann bestehende Hypothesen zur Einbindung dieses Kortexareals in den Gedächtnisprozess stützen. Daneben weisen die Ergebnisse der präfrontalen Stimulation im Vergleich zur Scheinstimulation in Verbindung mit der Einschätzung der subjektiven Beeinträchtigung auf die Bedeutung der Kontrolle von Stimulationsnebenwirkungen hin

Prodromal Huntington disease as a model for functional compensation of early neurodegeneration

<p>Single subject data underlying figures and tables in the published paper</p> <p>HD: Huntington disease gene carriers</p> <p>CON: healthy controls</p

Prevalence and Assessment of Internet Gaming Disorder in Psychiatric Outpatient Treatment

&lt;jats:p&gt; Abstract: Aim: While Internet Gaming Disorder (IGD) in the general population has a prevalence of 0.6-3.5 %, its frequency and relevance among clinical samples remains unclear. The present investigation aims at assessing the prevalence of IGD in an adult sample in a German psychiatric outpatient clinic and to identify potential predictors that could be helpful for screening for IGD. Methods: We performed a naturalistic retrospective study on data collected via a self-report survey including the Ten Item Internet Gaming Disorder Test (IGDT10). Problematic gaming was defined as either reaching the proposed IGDT10 cut-off for IGD or “gamer at risk” or having self-reported problems and negative consequences related to gaming. Age, gender, comorbid diagnoses and response patterns in the IGDT10 were analyzed. Results: 299 outpatients participated in the survey, with 54 % confirming engagement in gaming. 2.0 % (n=6) of the participants fulfilled the diagnostic criteria for IGD and almost all of these (n=5) gave a self-report of problems related to gaming. 5.0 % of the participants met our wider definition of problematic gaming (n=15; 13 male; mean age= 25.3 years). Conclusion: The prevalence of IGD-affected patients resembled results found in epidemiological studies in the general population. Analyses suggest that for an effective screening assessment, particularly questions regarding subjective impairment related to gaming patterns could be helpful. &lt;/jats:p&gt