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The present study explored the neurophysiological correlates of perception and recognition of emotional facial expressions in adolescent anorexia nervosa (AN) patients using event-related potentials (ERPs). We included 20 adolescent girls with AN and 24 healthy girls and recorded ERPs during a passive viewing task and three active tasks requiring processing of emotional faces in varying processing depths; one of the tasks also assessed emotion recognition abilities behaviourally. Despite the absence of behavioural differences, we found that across all tasks AN patients exhibited a less pronounced early posterior negativity (EPN) in response to all facial expressions compared to controls. The EPN is an ERP component reflecting an automatic, perceptual processing stage which is modulated by the intrinsic salience of a stimulus. Hence, the less pronounced EPN in anorexic girls suggests that they might perceive other people’s faces as less intrinsically relevant, i.e. as less “important” than do healthy girls.

Anorexia nervosa (AN) has been suggested to be associated with abnormalities in facial emotion recognition. Most prior studies on facial emotion recognition in AN have investigated adult samples, despite the onset of AN being particularly often during adolescence. In addition, few studies have examined whether impairments in facial emotion recognition are specific to AN or might be explained by frequent comorbid conditions that are also associated with deficits in emotion recognition, such as depression. The present study addressed these gaps by investigating recognition of emotional facial expressions in adolescent girls with AN (n = 26) compared to girls with major depression (MD; n = 26) and healthy girls (HC; n = 37). Participants completed one task requiring identification of emotions (happy, sad, afraid, angry, neutral) in faces and two control tasks. Neither of the clinical groups showed impairments. The AN group was more accurate than the HC group in recognising afraid facial expressions and more accurate than the MD group in recognising happy, sad, and afraid expressions. Misclassification analyses identified subtle group differences in the types of errors made. The results suggest that the deficits in facial emotion recognition found in adult AN samples are not present in adolescent patients.

Smoking is among the leading causes of mortality worldwide. Discontinuing smoking can increase life expectancy to the presmoking level. Unaided attempts are often ineffective, strengthening the necessity of cognitive-behavioral therapy (CBT), nicotine replacement or pharmacotherapy. Still, relapse rates are high. Recently, a modulation of nicotine craving, which predicts relapse, through transcranial magnetic stimulation to the prefrontal cortex was shown. In a pilot study, we investigated whether 4 sessions of intermittent theta burst stimulation (iTBS) as add-on treatment to CBT reduces nicotine craving and improves long-term abstinence (at 3, 6 and 12 months). Smokers were randomly assigned to a treatment (n = 38) or a sham group (n = 36). Although we did not find reduced craving, we could show higher abstinence rates in the treatment group at 3 months. At 6 and 12 months abstinence rates did not differ significantly. Results at 12 months, however, have to be interpreted cautiously due to significant differences in the dropout rates between the two groups at this time point. We provide first evidence for a beneficial effect of additional iTBS on intermediate nicotine abstinence; however, the low number of iTBS sessions might have prevented longer effects. More lasting effects might be achieved by iTBS maintenance sessions in analogy to the treatment of depression.

Replicating thought suppression effects with the Think/No-Think paradigm (TNT) has failed in some studies investigating the phenomenon of below-baseline recall of suppressed stimuli. Attempts have been made to isolate factors that might explain inter-individual differences in suppression performance. Certain personality traits, whether associated with a pathological state or investigated in a community sample, have been shown to interfere with successful thought suppression and might be responsible for some of the negative results obtained in TNT studies. In the present study we investigate the influence of psychometric measures of depression and anxiety in a fairly large sample of healthy volunteers. We show that high brooding and anxious tendencies predict worse suppression performance. While no suppression was shown when investigating the TNT not taking the psychometric measures into account, including these two traits in the analysis resulted in a pattern of below-baseline recall only for low brooders and low anxious participants. We argue that inclusion of variables measuring personality traits is warranted using the TNT and that these variables already exert their influence at minimal levels of variance, significantly improving the interpretability of the results. Future research should therefore cautiously investigate potential confounding personality characteristics before analysing their data.

Randomness of functional Magnetic Resonance Imaging (fMRI) resting-state time-series has recently been used as a biomarker for numerous disorders including Alzheimer's and Parkinson's disease as well as autism. To date, however, it remains unknown whether and to what degree personality traits are associated with the randomness of resting-state temporal dynamics. To investigate this question, we estimated the Hurst exponent - a measure of the randomness of a time-series - during resting-state fMRI in brain areas previously associated with trait Impulsivity as defined in Gray's Reinforcement Sensitivity Theory of Personality in 15 healthy individuals. The Hurst exponent in the ventral striatum as well as in the orbitofrontal cortex (OFC) was significantly associated with the measure of Gray's trait Impulsivity. Specifically, more random resting-state neural dynamics corresponded to higher Impulsivity scores both in the ventral striatum (r(15)=-.71; p=.003) and the OFC (r(15)=-.81; p

Impulsivity is a trait shared by many psychiatric disorders and therefore a suitable intermediate phenotype for their underlying biological mechanisms. One of the molecular determinants involved is the NOS1 ex1f‐VNTR, whose short variants are associated with a variety of impulsive behaviors. Fifty‐six healthy controls were stratified into homozygous long (LL) (30 probands) and short (SS) (26 probands) allele groups. Subjects completed a combined stop‐signal go/nogo task, while the oxygenation in the prefrontal cortex was measured with functional near‐infrared spectroscopy. Electromyography was recorded to control for differences in muscle activity in the two inhibition tasks. Two questionnaires on impulsive traits were completed. Differences between the two tasks are shown by distinct activation patterns within the prefrontal cortex. The nogo task resulted mainly in the activation of the dorsolateral prefrontal cortex (dlPFC), whereas successful and unsuccessful inhibition in the stop‐signal task elicited the predicted activity in the inferior frontal cortex (IFC). Although significant differences were found in neither the scores obtained on impulsivity‐related questionnaires nor the behavioral data, the LL group displayed increased dlPFC activity during nogo trials and the predicted activation in the IFC during successful inhibition in the stop‐signal task, while no significant activation was found in the SS group. Our data confirm an influence of NOS1 ex1f‐VNTR on impulsivity, as carriers of the short risk allele exhibited diminished activity of (pre‐)frontal brain regions during the inhibition in a stop‐signal task. Impairment of prefrontal control with consecutive failure of inhibitory processes might underlie association findings reported previously. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.

Pharmacological magnetic resonance imaging (phMRI) is a method to study effects of psychopharmacological agents on neural activation. Changes of the blood oxygen level dependent (BOLD), the basis of functional MRI (fMRI), are typically obtained at relatively high sampling frequencies. This has more recently been exploited in the field of fMRI by applying independent component analysis (ICA), an explorative data analysis method decomposing activation into distinct neural networks. While already successfully used to investigate resting network and task-induced activity, its use in phMRI is new. Further extension of this method to tensorial probabilistic ICA (tensor PICA) allows to group similar brain activation across the anatomical, temporal, subject or session domain. This approach is useful for pharmacological experiments when no pharmacokinetic model exists. We exemplify this method using data from a placebo-controlled cholecystokinine-4 (CCK-4) injection experiment performed on 16 neuropsychiatrically and medically healthy males (age 25.6 +/- 4.2 years). Tensor PICA identified strong increases in activity in 12 networks. Comparison with results gained from the standard approach (voxelwise regression analysis) revealed good reproduction of areas previously associated with CCK-4 action, such as the anterior cingulate, orbitofrontal cortex, cerebellum, temporolateral, left parietal and insular areas, striatum, and precuneus. Several other components such as the dorsal anterior cingulate and medial prefrontal cortex were identified, suggesting higher sensitivity of the method. Exploration of the time courses of each activated network revealed differences, that might be lost when a fixed time course is modeled, e. g. neuronal responses to an acoustic warning signal prior to injection. Comparison of placebo and CCK-4 runs further showed that a proportion of networks are newly elicited by CCK-4 whereas other components are significantly active in the placebo conditions but further enhanced by CCK-4. In conclusion, group ICA is a promising tool for phMRI studies that allows quantifying and visualizing the modulation of neural networks by pharmacological interventions.

Nitric oxide (NO) synthase produces NO, which serves as first and second messenger in neurons, where the protein is encoded by the NOS1 gene. A functional variable number of tandem repeats (VNTR) polymorphism in the promoter region of the alternative first exon 1f of NOS1 is associated with various functions of human behavior, for example increased impulsivity, while another, non-functional variant was linked to decreased verbal working memory and a heightened risk for schizophrenia. We therefore investigated the influence of NOS1 ex 1f-VNTR on working memory function as reflected by both behavioral measures and prefrontal oxygenation. We hypothesized that homozygous short allele carriers exhibit altered brain oxygenation in task-related areas, namely the dorsolateral and ventrolateral prefrontal cortex and the parietal cortex. To this end, 56 healthy subjects were stratified into a homozygous long allele group and a homozygous short allele group comparable for age, sex and intelligence. All subjects completed a letter n-back task (one-, two-, and three-back), while concentration changes of oxygenated (O 2 Hb) hemoglobin in the prefrontal cortex were measured with functional near-infrared spectroscopy (fNIRS). We found load-associated O 2 Hb increases in the prefrontal and parts of the parietal cortex. Significant load-associated oxygenation differences between the two genotype groups could be shown for the dorsolateral prefrontal cortex and the parietal cortex. Specifically, short allele carriers showed a significantly larger increase in oxygenation in all three n-back tasks. This suggests a potential compensatory mechanism, with task-related brain regions being more active in short allele carriers to compensate for reduced NOS1 expression.

Over the past years functional near-infrared spectroscopy (fNIRS) has substantially contributed to the understanding of language and its neural correlates. In contrast to other imaging techniques, fNIRS is well suited to study language function in healthy and psychiatric populations due to its cheap and easy application in a quiet and natural measurement setting. Its relative insensitivity for motion artifacts allows the use of overt speech tasks and the investigation of verbal conversation. The present review focuses on the numerous contributions of fNIRS to the field of language, its development, and related psychiatric disorders but also on its limitations and chances for the future.

The current pilot study was designed to investigate mechanisms of suppression of emotional and non-emotional words with Anderson's Think/No-Think paradigm using functional near-infrared spectroscopy (fNIRS). We found no differences in the suppression of negative, positive and neutral words on the behavioral level. Neurophysiological data, however, have shown more activation in right dlPFC and right vlPFC during attempts to suppress negative stimuli than during attempts to suppress neutral or positive stimuli. Our results thus provide further insights into the different mechanisms of voluntary thought suppression, recruited for the inhibition of thoughts of neutral, negative or positive content. Thereby, they provide a basis for continuing this line of research in a psychiatric sample of patients with Major Depressive Disorder and Panic Disorder, both disorders associated with persistent attempts to manipulate emotional memories.

Background Because standard repetitive transcranial magnetic stimulation (rTMS) protocols exhibit post-stimulus effects of short duration, novel protocols such as theta burst stimulation (TBS), are promising approaches to enhance the effectiveness of rTMS. However, little is known about the side effect profile of such protocols. Thus, the present study explores whether TBS is safe particularly in terms of effects on cognition, mood, and electroencephalogram (EEG) measures in healthy subjects. Methods Twenty-four healthy volunteers participated in 2 randomized, placebo-controlled, cross-over experiments and underwent continuous TBS (cTBS), intermittent TBS (iTBS), and shamTBS either over the left dorsolateral prefrontal cortex (DLPFC, n = 12) or the medial prefrontal cortices (mPFC, n = 12). Clinical side effects, performance in a neuropsychological battery, mood changes, and resting EEG were recorded. Results Neither a seizure nor epileptiform EEG activity was observed . The most prominent side effect was the occurrence of vagal reactions during TBS; otherwise no serious side effects were found. Standardized low-resolution brain electromagnetic tomography showed current density changes in the α2 band after iTBS of the DLPFC, which remained detectable up to 50 min after stimulation. The few changes in neuropsychological performance were concordant with stimulation site. No impact on mood was detected. Conclusions Although TBS protocols of the human prefrontal cortex seem to be safe in healthy subjects, future studies need to address the occurrence of vagal reactions. Excitatory and inhibitory properties of motor cortex TBS might not be transferable to prefrontal sites, and the action of specific TBS protocols needs to be further investigated prior to clinical application.