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After acute infection with the SARS-CoV-2 virus, a considerable number of patients remains symptomatic with pathological changes in various organ systems. This study aimed to relate the physical and mental burden of symptoms of long COVID patients to the findings of a somatic evaluation. In patients with persistent long COVID symptoms three months after acute infection we assessed physical and mental health status using the SF-36 questionnaire. The cohort was dichotomised by the results (upper two quartiles vs. lower to quartiles) and compared with regard to transthoracic echocardiography, body plethysmography (including diffusion capacity), capillary blood gas analysis and 6-min walk test (6-MWT). From February 22 to September 13, 2021, 463 patients were prospectively examined, of which 367 completed the SF-36 questionnaire. A positive correlation between initial disease severity (need for hospitalization, intensive care medicine) and resulting symptom burden at follow-up could be demonstrated. Patients with impaired subjective physical and mental status were significantly more likely to be women. There was a significant correlation between symptom severity and reduced exercise tolerance in the 6-MWT (495.6 ± 83.7 m vs 549.7 ± 71.6 m, p

Investigation of the experiences of depressed fathers in dealing with their depressive disorder in the family.17 semi-structured narrative interviews were conducted and analyzed following a Grounded Theory Approach.Fathers describe individual coping strategies in dealing with their depressive disorder that aim at independently coping from their family (self-management, [non])disclosure of the disorder).Fathers should be supported in (the decision-making process of) disclosing their illness to the family and developing coping strategies that take family needs further into account.Untersuchung von Erfahrungen depressiv erkrankter Väter zum Umgang mit der Erkrankung in der Familie.17 teilstrukturierte Interviews wurden entlang der Grounded Theory Methodology durchgeführt und analysiert.Väter beschreiben überwiegend Strategien im Umgang mit ihrer depressiven Erkrankung, die eine Bewältigung unabhängig von der Familie vorsehen (Selbstmanagement, [Nicht-]Sprechen über die Erkrankung).Väter brauchen Unterstützung in der (Entscheidung zur) Offenlegung ihrer Erkrankung gegenüber der Familie sowie für die Entwicklung von Bewältigungsstrategien, die Bedarfe der Familie stärker berücksichtigen.

IntroductionThe COVID-19 pandemic resulted in severe detrimental effects on the mental well-being of health care workers (HCW). Consequently, there has been a need to identify health-promoting resources in order to mitigate the psychological impact of the pandemic on HCW.ObjectiveOur objective was to investigate the association of sense of coherence (SOC), social support and religiosity with self-reported mental symptoms and increase of subjective burden during the COVID-19 pandemic in HCW.MethodsOur sample comprised 4324 HCW of four professions (physicians, nurses, medical technical assistants (MTA) and pastoral workers) who completed an online survey from 20 April to 5 July 2020. Health-promoting resources were assessed using the Sense of Coherence Scale Short Form (SOC-3), the ENRICHD Social Support Inventory (ESSI) and one item on religiosity derived from the Scale of Transpersonal Trust (TPV). Anxiety and depression symptoms were measured with the PHQ-2 and GAD-2. The increase of subjective burden due to the pandemic was assessed as the retrospective difference between burden during the pandemic and before the pandemic.ResultsIn multiple regressions, higher SOC was strongly associated with fewer anxiety and depression symptoms. Higher social support was also related to less severe mental symptoms, but with a smaller effect size, while religiosity showed minimal to no correlation with anxiety or depression. In professional group analysis, SOC was negatively associated with mental symptoms in all groups, while social support only correlated significantly with mental health outcomes in physicians and MTA. In the total sample and among subgroups, an increase of subjective burden was meaningfully associated only with a weaker SOC.ConclusionPerceived social support and especially higher SOC appeared to be beneficial for mental health of HCW during the COVID-19 pandemic. However, the different importance of the resources in the respective occupations requires further research to identify possible reasons.

To meet mental health needs in men with depression, gender sensitive services are needed and recommended. Therefore, mental health professionals' views on care needs among men with depression that should be met by gender-sensitive services were assessed and consequences for inpatient treatment are considered.Semi-structured interviews were conducted with 33 mental health professionals focusing on men's specific needs in depression treatment against the background of male gender role expectations. Qualitative Content Analysis was performed using MAXqda-Software.Men with depression benefit from individual talk with staff and structured activity during treatment. Men-only groups are assessed as enabling critical reflection of aspects of masculinity. Physical activities and handicraft enable men to examine their performance level. Services focusing on men's specific needs are assessed as helpful but largely inexistent.Expectations of social gender roles and their implications for mental health treatment should be considered in both mental health professional training and mental health treatment.Befragung psychiatrischer Fachkräfte zu geschlechtsspezifischen Bedarfen depressiver Männer und Behandlungsziele für die stationäre Versorgung.Semistrukturierte Interviews.Männergruppen ermöglichen die Reflexion von Geschlechtsrollenerwartungen. Aktivitätsbezogene Angebote helfen betroffenen Männern, ihre Leistungsfähigkeit einzuschätzen und bieten Erfolgserlebnisse. Sie sind im Behandlungsspektrum unzureichend abgebildet.Die Bedeutung normativer Rollenerwartungen sollte in der Ausbildung psychiatrischer Fachkräfte berücksichtigt werden.

BackgroundThe underestimation of depression among men may result from atypical depression symptoms and male help-seeking behaviour. However, higher suicide rates among men than among women indicate a need for gender-specific services for men with depression. In order to develop gender-specific services, it is essential to examine professionals’ attitudes towards men’s depressive symptoms and treatment needs as well as barriers to and facilitators of treatment. This study examined gender-specific treatment needs in male patients and treatment approaches to male patients from a professional perspective.MethodsSemi-structured face-to-face interviews were conducted with 33 mental health professionals (MHPs) from five German psychiatric institutions. The study assessed the characteristics and attributes of male patients with depression risk factors for the development of depression among men, their condition at the beginning of treatment, male patients’ depressive symptoms, the needs and expectations of male patients, the importance of social networks in a mental health context, and MHPs’ treatment aims and treatment methods. Transcripts were analysed using qualitative content analysis.ResultsThe professionals’ reference group of male patients were men who were characterised in accordance with traditional masculinity. Attributes reported as in line with this type of men were late initiations of inpatient treatment after crisis, suicidal ideation or attempted suicide, and high expectations towards treatment duration, success rate in recovery and therapeutic sessions. In contrast, male patients who deviate from these patterns were partially described with reference to female stereotypes. Professionals referred to psychosocial models in their explanations of the causes of depression and provided sociological explanations for the development of masculine ideals among men. The consequences of these for treatment were discussed against the background of normative expectations regarding the male gender. From the professionals’ point of view, psychoeducation and the acceptance of depression (as a widespread mental illness) were the most important goals in mental health treatment.ConclusionsIn order to improve mental health among men, gender-specific services should be offered. Awareness of the role of gender and its implications on mental health treatment should be an integral part of MHPs’ education and their daily implementation of mental health treatment practices.

Purpose A traditional male role orientation is considered to increase the risk of depression and preventing men from disclosing symptoms of mental illness and seeking professional help. Less is known about the variance of masculinity orientations in men already treated for depression and their role in the treatment process. In this study, patterns of masculinity norms and work role orientations will be identified among men treated for depression. Associations of these patterns with depressive symptoms, stigma and delay in professional help-seeking will be investigated. Methods In a cross-sectional study, male role orientations (MRNS), work-related attitudes (AVEM), symptoms of mental disorders (PHQ), and attitudes related to stigma of mental illness (DSS) were assessed by standardized methods in a sample of 250 men treated for depression in general medical, psychiatric and psychotherapeutic services. Data were analyzed by means of latent profile analysis (LPA), by multinomial and linear regression models, and by path analysis. Results The results of LPA revealed three latent classes of men treated for depression. Men assigned to class one reported a less traditional male role orientation, low professional ambitions and low coping capacities; men assigned to class two reported a traditional masculinity orientation, high professional ambitions but low coping capacities; men assigned to class three reported less traditional masculinity tended orientations, medium professional ambitions and high coping capacities. Men assigned to classes one and two to have more stigmatizing attitudes, longer periods of untreated illness and more severe symptoms of mental disorders, in comparison to men assigned to class three. Conclusions Overall, this study reveals that traditional masculinity norms and work-role orientations in men treated for depression are associated with a worse mental health status. Our study results also suggest that a slackening of traditional masculinity norms is associated with improved psychological well-being if it does not coincide with a complete distancing from professional ambitions and a lack of ability to cope with professional stress.

Theoretical models of dopamine function stemming from reinforcement learning theory have emphasized the importance of prediction errors, which signal changes in the expectation of impending rewards. Much less is known about the effects of mean reward rates, which may be of motivational significance due to their role in computing the optimal effort put into exploiting reward opportunities. Here, we used a reinforcement learning model to design three functional neuroimaging studies and disentangle the effects of changes in reward expectations and mean reward rates, showing recruitment of specific regions in the brainstem regardless of prediction errors. While changes in reward expectations activated ventral striatal areas as in previous studies, mean reward rates preferentially modulated the substantia nigra/ventral tegmental area, deep layers of the superior colliculi, and a posterior pontomesencephalic region. These brainstem structures may work together to set motivation and attentional efforts levels according to perceived reward opportunities.

In order to develop gender-sensitive services, there is a need to better understand coping among men with depression. The study aims to analyze the meaning of gender- and work-related roles for illness theories and coping among men with depression.Based on a latent class analysis of three types of masculinities, biographical interviews were conducted with men with depression (n = 12). Transcripts were analyzed using a hermeneutic-reconstructive approach that includes subjective constructions of meaning related to (1) illness theories, (2) coping and (3) help-seeking behavior.Whereas most interviewees reported the role of family-related career orientation as a cause of depression, results differ in terms of coping. While participants partly distanced themselves from external expectations, some tried to keep up their employability. Others perceived their depression as a chance as well as an opportunity to change harmful attitudes.Psychiatric services might consider different priorities referring to work and life and their impact on coping with depression among men.Analyse der Bedeutung von männlichkeits- und berufsrollenbezogenen Orientierungsmustern für Krankheitstheorien und Bewältigung bei depressiv erkrankten Männern.Rekonstruktive Auswertung biografisch-narrativer Interviews von 12 Männern mit depressiver Erkrankung.Die berufsrollenbezogene Orientierung wird generell als Ursache der depressiven Erkrankung genannt. Gleichzeitig zeigen sich Unterschiede im Verständnis sowie in der Bewältigung der depressiven Erkrankung. Während ein Teil der Befragten trotz der berufsbedingten Krisenerfahrung an der beruflichen Orientierung festhält, nutzen andere die Depression als Chance zur Veränderung gesundheitsschädlicher Lebens- und Arbeitsentwürfe.Prioritäten in Bezug auf Arbeits- und Lebensentwürfe und deren Bedeutung für die Krankheitsbewältigung sollten in der Behandlung thematisiert werden.

Background: Increasing recognition is being given to the importance of cognitions observed in posttraumatic conditions. These cognitions may reflect the activation of negative schemas. The aim of this work was to evaluate the feasibility of the scrambled-sentences task (SST) to assess individual differences in attributions commonly observed after traumas. Originally developed to assess the tendency to activate negative cognitions in individuals predisposed to depression, the SST is a laboratory task the outcome of which has been shown to predict depression relapse and is associated with depressiveness. Sampling and Methods: We used content from self-rating scales for assessment of the activation of trauma-related schemas to develop a trauma-related SST and evaluated its performance in a behavioral study (n = 43) and a functional neuroimaging study (n = 20). Results: In the healthy sample in which we tested it, the trauma-related SST was strongly associated with individual differences in negative affect (scores in depressiveness and neuroticism scales) as well as with the scores on trauma-related cognition scales. However, we failed to detect a clear specificity of trauma-related cognitions in correlations with scores on the trauma-related scales in the healthy participants. The neuroimaging data demonstrated activation of a ventral network of areas that included the perisylvian/temporal cortex and the peri­cingular cortex in handling trauma-related relative to neutral material, replicating previous neuroimaging studies of the SST. Conclusion: The shattered-assumptions SST demonstrated strong associations with individual differences in all of the rating scales used in the study, suggesting its usefulness in capturing aspects of affective psychopathology. The neuroimaging study confirmed the capacity of this task to elicit specific activations. In future studies, evaluation of the conditions in which these neural substrates are active may shed light on the mechanism of schema selection.

The present functional neuroimaging study focuses on the iconography of mourning. A culture-specific pattern of body postures of mourning individuals, mostly suggesting withdrawal, emerged from a survey of visual material. When used in different combinations in stylized drawings in our neuroimaging study, this material activated cortical areas commonly seen in studies of social cognition (temporo-parietal junction, superior temporal gyrus, and inferior temporal lobe), empathy for pain (somatosensory cortex), and loss (precuneus, middle/posterior cingular gyrus). This pattern of activation developed over time. While in the early phases of exposure lower association areas, such as the extrastriate body area, were active, in the late phases activation in parietal and temporal association areas and the prefrontal cortex was more prominent. These findings are consistent with the conventional and contextual character of iconographic material, and further differentiate it from emotionally negatively valenced and high-arousing stimuli. In future studies, this neuroimaging assay may be useful in characterizing interpretive appraisal of material of negative emotional valence.

Objective The aim of this cross-sectional web-based study was to examine self-reported mental distress, psychosocial burdens, working conditions and potential risk and protective factors for depressive and anxiety symptoms during the COVID-19 pandemic in health care workers (HCW). Methods In the largest survey on mental health of HCW conducted during the first wave of COVID-19 in Europe (N = 8071 HCW), we investigated depressive (Patient Health Questionnaire-2, PHQ-2), and anxiety symptoms (Generalized Anxiety Disorder-2, GAD-2), working conditions, and psychosocial burden of 3678 HCW of three health care professions in hospitals: physicians (n = 1061), nurses (n = 1275), and medical technical assistants (MTA, n = 1342). Results The prevalence of clinically significant levels of depressive and anxiety symptoms was 17.4% and 17.8% for physicians, 21.6% and 19.0% for nurses, and 23.0% and 20.1% for MTA, respectively. All three professions demonstrated significantly elevated PHQ-2 and GAD-2 scores, when compared with general German population before the pandemic, but lower scores in relation to that during the pandemic. Multiple linear regression analyses revealed that higher levels of depressive symptoms were associated with insufficient recovery during leisure time, increased alcohol consumption, and less trust in colleagues in difficult situations at work. In addition, elevated anxiety scores were related to increased fear of becoming infected with COVID-19. Conclusion During the pandemic HCW demonstrated a lower burden of mental distress compared to the general population. Nevertheless, a high percentage of HCW demonstrates psychosocial distress, so that the establishment of regular mental health screening and prevention programmes for HCW is indicated.

Functional imaging studies of affective disorders have demonstrated abnormal activity in the amygdala in response to emotionally salient stimuli. Since in other studies this response has been shown to habituate during the scanning session, it is not clear if it may be of use in monitoring disease progression or remission, or in monitoring the effects of therapy, as habituation may confound normalisation of response. We investigated here amygdala activation in healthy participants exposed to displays of emotional facial expressions in a sample of N = 31 individuals assessed twice in an interval of three weeks. At this interval no habituation could be detected, suggesting the validity of this imaging assay in repeated assessments of amygdalar reactivity. However, the fusiform gyrus and the inferior frontal lobes showed decreases in activations that may be related to the role of these areas in encoding visual and emotional aspects of the stimuli.

In a previous study we showed that errors following errors activate a strategic (prefrontal) mechanism. In an error trial (trial n) following an erroneous previous trial (trial n - 1) healthy control subjects were found to have enlarged (more negative) amplitudes of the error related negativity (ERN)/error negativity (Ne), an electrophysiological correlate of response monitoring, in response to a negative feedback signal. Contrary to that, patients with major depressive disorder showed smaller (less negative) ERN/Ne amplitudes. It has been discussed controversially whether errors of choice (e.g., pressing an incorrect response button in an Eriksen flanker task) and errors of commission (e.g., pressing a button when one is not supposed to in a Go/Nogo task) are related to different ERN/Ne mechanisms. In the present study, we examined whether our previous result only holds for errors of choice in an Eriksen flankers task or extends to errors of commission in a Go/Nogo task, as well. Ten patients with DSM-IV major depressive disorder and 10 matched controls participated in a Go/Nogo task with performance feedback which signaled monetary reward. Patients with major depressive disorder again showed a less negative ERN/Ne amplitude in error trials following error trials. This result might reflect impaired response monitoring processes in major depressive disorder resulting from an impaired activation of a central reward pathway and/or a deficit in strategic reasoning.

Psychosomatic symptoms often present within the vocational context. The unmet need for easily accessible and early interventions led to the development of a variety of offers in this area. From a scientific point of view, the question of how such a "psychosomatic consultation in the workplace" (PCIW) is best conceptualized remains open.We analysed treatment documentation for all patients of two recently established PCIW from January 2011 to January 2012 both descriptively and by qualitative content analysis.A total of 67 patients were seen, 75% of whom were male. For 75% of users PCIW constituted the first contact with psychosomatic-psychotherapeutic-psychiatric services. For about 80%of the patients a work-related aetiology could be considered. 40%of patients were recommended to outpatient psychotherapeutic care.PCIW represents an easily accessible therapeutic offer in the vocational context. There often is a mix of work-related and personal problems that suggests the cooperation of occupational and psychosomatic physicians.

Objective Surveys assessing alcohol use among physicians have most commonly employed the Alcohol Use Disorders Identification Test (AUDIT) or the AUDIT-C, the most common short version of the AUDIT. As with other screeners, prevalence estimation is dependent on the accuracy of the test as well as choice of the cutoff value. The aim of the current study is to derive more precise prevalence estimates of alcohol problems in physicians by correcting for false-positive and false-negative results. Method In the context of a survey, the AUDIT was sent out via email or standard postal service to all 2484 physicians in Salzburg, Austria. A total of 456 physicians participated. A published correction formula was used to estimate the real prevalence of alcohol use problems. Results Applying a cutoff of 5 points for the AUDIT-C, 15.7% of female and 37.7% of male physicians screened positive. Use of a correction based on general population data and the sensitivity and specificity of the AUDIT-C resulted in much lower prevalence rates: 4.0% for female and 9.5% for male physicians. Using the full AUDIT, 19.6% of the female physicians and 48% of the male physicians were screened positive. Using the correction, the estimated prevalence rates for females and males were 6.3% and 15.5%, respectively. Conclusions Our findings demonstrate that uncorrected screening results may markedly overestimate the prevalence of physicians drinking problems.

Neuroimaging techniques such as magnetization transfer imaging allow the detection of microstructural alterations of tissue, and for this reason have been applied to the study of disorders such as schizophrenia. However, they are also sensitive to partial volume effects arising from mixed compartments, such as those comprising cerebral spinal fluid, which makes separate evaluation of volumetric and structural alterations difficult. Ensuing regional differences in the distribution of data and signal-to-noise ratio add further potential bias to their assessment. In the present study we simultaneously applied tissue segmentation, statistical imputation, and nonparametric inference to address these issues and improve the validity of statistical inference. In a case study of N = 32 schizophrenic patients matched to the same number of controls, we compared a standard voxel-based analysis with one supplemented by the imputation technique. We were able to replicate significant results in the imputed analysis and even extend them in the areas not excluded by excessive partial volume effects. Application of segmentation algorithms in this dataset also suggested that partial volume effects from spinal fluid potentially affect inference in most cortical gray matter, unless remedial steps are undertaken. Refined imputation methods may be particularly attractive in future research settings characterized by large samples and the availability of adequate computational resources.

The cytochrome P450 2D6 (CYP2D6) is a genetically polymorphic enzyme involved in the metabolism of several psychoactive drugs. Beside its expression in the liver, CYP2D6 is highly expressed in several regions of the brain, such as the hippocampus, thalamus, hypothalamus and the cortex, but its function in the brain is not well understood. The CYP2D6 enzyme may also have a physiological role due to its involvement in neurotransmitter biotransformation. In this study, CYP2D6 genotyping was performed in N=188 healthy individuals and compared with brain perfusion levels at rest, which may reflect an ongoing biological process regulating the reactivity of the individual to emotional stimuli and the detection of signals evoking fear. Relative to N=42 matched extensive metabolizers, N=14 poor metabolizers were associated with 15% higher perfusion levels in the thalamus (P=0.03 and 0.003). Effects were also present in the whole (N=188) sample divided into metabolizer groups, or finely graded into seven CYP2D6 activity levels. A weaker effect was observed in the right hippocampus (P=0.05). An exploratory analysis, extended to the whole brain, suggested the involvement of CYP2D6 in regions associated with alertness or serotonergic function. These findings support the hypothesis of a functional role of CYP2D6 in the brain.

Background Atomoxetine is a selective norepinephrine reuptake inhibitor clinically used for treatment of attention-deficit/hyperactivity disorder. In healthy control subjects, doses of 40 mg or 60 mg improved inhibitory control in combination with modulation of prefrontal cortex functioning. We investigated the effects of atomoxetine (80 mg) on error monitoring as a second key component of cognitive control. Methods Twelve healthy, male volunteers were included in a randomized double-blind, placebo-controlled, within-subjects design to examine the effects of a single dose of atomoxetine on neural activities during a combined Eriksen flanker-Go/NoGo task as measured by functional magnetic resonance imaging. Results Behaviorally, atomoxetine led to a significant increase in failed inhibition. Functionally, interaction analysis revealed a significant increase of the error signal (incorrect minus correct NoGo trials) under atomoxetine in bilateral inferior frontal cortex and presupplementary motor area. Drug-dependent increases in error signaling did not correlate with increased error rates. Analysis of neuropsychological data indexed a significant increase in phasic alertness. Conclusions Results support that atomoxetine increases neural sensitivity for errors in healthy control subjects, possibly due to an accentuated representation of the task set. However, this gain was accompanied by deterioration in inhibitory control, possibly reflecting a shift beyond the optimal working range of the norepinephrine system.

[Background] The serotonin transporter length repeat polymorphism (5-HTTLPR) in the promoter region of the serotonin transporter gene (SLC6A4) has been associated in healthy subjects with changes in basal perfusion levels in the limbic system and ventral prefrontal areas, regions involved in the pathophysiology of depression and anxiety, suggesting the existence of a neurobiological trait predisposing to these disorders. We reassess the findings of an increased baseline perfusion in the amygdala and ventral prefrontal areas in healthy carriers of the risk genotype in a much larger sample than in previous studies., [Methods] A cohort of 183 healthy European individuals underwent perfusion imaging with continuous arterial spin-labeling (CASL) while resting quietly in the scanner for 8 minutes. Participants were genotyped to assess the occurrence of the short allele and the Lg and La variants of the long repeat., [Results] No association between the 5-HTTLPR polymorphism and baseline brain perfusion was detected in the regions of interest or elsewhere in the brain. In the amygdala, variability in baseline perfusion was explained in large part by global cerebral flow levels (between 50% and 55%), in minor part by sex (between 4% and 5%), but not by genotype (less than .5%). Power analyses showed that the study was of sufficient size to be informative., [Conclusions] The findings did not confirm the existence of a biological marker of the effect of 5-HTTLPR polymorphism in the amygdala or in the orbitofrontal cortex. © 2010 Society of Biological Psychiatry.

Early studies of rest cerebral metabolism and perfusion reported no association with intellectual capacity. We revisit this issue using a larger sample (N=146) and a continuous arterial spin labeling technique to measure perfusion, and working memory capacity as a measure of intellectual capacity. In the cortex, working memory capacity correlated diffusely and negatively with perfusion. This negative association was more marked in the prefrontal and temporal cortex of the left hemisphere. However, there were also weak positive correlations in the auditory areas, accompanied by analogous correlations in all other areas associated with sensory modalities, with a preference for right lateralization. These findings are discussed in terms of the cortical and vascular organization of the brain.

Simple baseline studies correlate average perfusion levels measured at rest with individual variables, or contrast subject groups as in case-control studies. In this methodological work, we summarize some formal properties of the design of these studies, and investigate the sources of variance that characterize data acquired with the arterial spin labeling technique, with the purpose of alerting users to the main sources of variation that determine background variance and affect the power of statistical tests. This design typology is characterized by two variance components: between acquisitions and between subjects. We show that variation between acquisitions is affected by the presence of large vessels and venous sinuses, with potential adverse effects especially in the temporal and insular regions, and provide maps of the number of acquisitions or subjects required to reach the desired estimate precision. Furthermore, we show that the largest source of variation between subjects is captured by global perfusion levels, and can in principle be removed by adjusting the data. Significance levels, however, are not always only improved by the adjustment procedure; we provide an example in the correlation with age, and attempt to explain the consequences of the adjustment with the help of a principal component analysis of the data. We also show the existence of variation between subjects in the perfusion in the territory of the posterior cerebral artery and in hemispheric asymmetry.

Major depressive disorder (MDD) can be characterized by a wide-ranging profile of cognitive deficits including attention, memory, and executive functions which is possibly due to reduced volumes and a hypometabolism of the anterior cingulate cortex, orbitofrontal, and dorsolateral prefrontal cortex. We examined 21 patients with MDD in partial remission and 21 age-, sex-, and education matched healthy controls using event-related potentials (ERPs). Participants performed a hybrid flanker Go/Nogo task while multichannel EEG was recorded. Two ERP components were of interest which repeatedly have been linked to response inhibition: the Nogo-N2 and the Nogo-P3 which can be observed in Nogo trials of a Go/Nogo task. MDD patients showed a specifically reduced Nogo-P3 while the Nogo-N2 and the P3b in Go trials were unaffected. These results provide further evidence of impaired response monitoring and control processes in patients with MDD.

We discuss the assessment of signal change in single magnetic resonance images (MRI) based on quantifying significant departure from a reference distribution estimated from a large sample of normal subjects. The parametric approach is to build a test based on the expected distribution of extrema in random fields. However, in conditions where the variance is not uniform across the volume and the smoothness of the images is moderate to low, this test may be rather conservative. Furthermore, parametric tests are limited to datasets for which distributional assumptions hold. This paper investigates resampling methods that improve statistical tests for signal changes in single images in such adverse conditions, and that can be used for the assessment of images taken for clinical purposes. Two methods, the bootstrap and cross‐validation, are compared. It is shown that the bootstrap may fail to provide a good estimate of the distribution of extrema of parametric maps. In contrast, calibration of the significance threshold by means of cross‐validation (or related sampling without replacement techniques) address three issues at once: improved power, better voxel‐by‐voxel estimate of variance by local pooling, and adaptation to departures from ideal distributional assumptions on the signal. We apply the cross‐validated tests to apparent diffusion coefficient maps, a type of MRI capable of detecting changes in the microstructural organization of brain parenchyma. We show that deviations from parametric assumptions are strong enough to cast doubt on the correctness of parametric tests for these images. As case studies, we present parametric maps of lesions in patients suffering from stroke and glioblastoma at different stages of evolution. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.

Background Images of perfusion estimates obtained with the continuous arterial spin labelling technique are characterized by variation between single acquisitions. Little is known about the spatial determinants of this variation during the acquisition process and their impact on voxel-by-voxel estimates of effects. Results We show here that the spatial patterns of covariance between voxels arising during the acquisition of these images uncover distinct mechanisms through which this variance arises: through variation in global perfusion levels; through the action of large vessels and other, less well characterized, large anatomical structures; and through the effect of noisy areas such as the edges of the brain. Conclusions Knowledge of these covariance patterns is important to experimenters for a correct interpretation of findings, especially for studies where relatively few acquisitions are made.