Emotional Stimuli In Patients Research Articles

Subacute alpha frequency (10Hz) subthalamic stimulation for emotional processing in Parkinson's disease

BackgroundPsychiatric comorbidities are common in Parkinson's disease (PD) and may change with high-frequency stimulation targeting the subthalamic nucleus. Numerous accounts indicate subthalamic alpha-frequency oscillation is implicated in emotional processing. While intermittent alpha-frequency (10Hz) stimulation induces positive emotional effects, with more ventromedial contacts inducing larger effects, little is known about the subacute effect of ventral 10Hz subthalamic stimulation on emotional processing. Objective/HypothesisTo evaluate the subacute effect of 10Hz stimulation at bilateral ventral subthalamic nucleus on emotional processing in PD patients using an affective task, compared to that of clinical-frequency stimulation and off-stimulation. MethodsTwenty PD patients with bilateral subthalamic deep brain stimulation for more than six months were tested with the affective task under three stimulation conditions (10Hz, 130Hz, and off-stimulation) in a double-blinded randomized design. ResultsWhile 130Hz stimulation reduced arousal ratings in all patients, 10Hz stimulation increased arousal selectively in patients with higher depression scores. Furthermore, 10Hz stimulation induced a positive shift in valence rating to negative emotional stimuli in patients with lower apathy scores, and 130Hz stimulation led to more positive valence to emotional stimuli in the patients with higher apathy scores. Notably, we found correlational relationships between stimulation site and affective rating: arousal ratings increase with stimulation from anterior to posterior site, and positive valence ratings increase with stimulation from dorsal to ventral site of the ventral subthalamic nucleus. ConclusionsOur findings highlight the distinctive role of 10Hz stimulation on subjective emotional experience and unveil the spatial organization of the stimulation effect.

Abnormal Regional Spontaneous Neural Activity and Functional Connectivity in Unmedicated Patients with Narcolepsy Type 1: A Resting-State fMRI Study.

Previous Resting-state functional magnetic resonance imaging (fMRI) studies have mainly focused on cerebral functional alteration in processing different emotional stimuli in patients with narcolepsy type 1 (NT1), but were short of exploration of characteristic brain activity and its remote interaction patterns. This study aimed to investigate the spontaneous blood oxygen fluctuations at rest and to elucidate the neural mechanisms underlying neuropsychiatric behavior. A total of 18 unmedicated patients with NT1 and matched healthy individuals were recruited in a resting-state fMRI study. Magnetic resonance imaging (MRI) data were first analyzed using fractional low-frequency amplitude of low-frequency fluctuation (fALFF) to detect changes in local neural activity, and regions with group differences were taken as regions of interest (ROIs). Secondly, functional connectivity (FC) analysis was used to explore altered connectivity between ROIs and other areas. Lastly, the relationship between functional brain activity and neuropsychiatric behaviors was analyzed with correlation analysis. fALFF analysis revealed enhanced neural activity in bilateral fusiform gyrus (FFG), right precentral gyrus, and left postcentral gyrus (PoCG) in the NT1 group. The patients indicated reduced activity in the bilateral temporal pole middle temporal gyrus (TPOmid), left caudate nucleus (CAU), left parahippocampus, left precuneus (PCUN), right amygdala, and right anterior cingulate and paracingulate gyri. ESS score was negatively correlated with fALFF in the right FFG. The NT1 group revealed decreased connectivity between left TPOmid and right PoCG, the bilateral middle frontal gyrus, left superior frontal gyrus, medial, and right supramarginal gyrus. Epworth Sleepiness Scale (ESS) was negatively correlated with FC of the left TPOmid with left putamen (PUT) in NT1. Compared with healthy controls (HCs), enhanced FC of the left CAU with right FFG was positively associated with MSLT-SOREMPs in patients. Furthermore, increased FC of the left PCUN with right PoCG was positively correlated with SDS score. We found that multiple functional activities related to the processing of emotional regulation and sensory information processing were abnormal, and some were related to clinical characteristics. fALFF in the left postcentral or right precentral gyrus may be used as a biomarker of narcolepsy, whereas fALFF in the right fusiform and the FC strength of the left temporal pole middle temporal gyrus with the putamen may be clinical indicators to assess the drowsiness severity of narcolepsy.

Are Brain Responses to Emotion a Reliable Endophenotype of Schizophrenia? An Image-Based Functional Magnetic Resonance Imaging Meta-analysis

BackgroundImpaired emotion processing constitutes a key dimension of schizophrenia and a possible endophenotype of this illness. Empirical studies consistently report poorer emotion recognition performance in patients with schizophrenia as well as in individuals at enhanced risk of schizophrenia. Functional magnetic resonance imaging studies also report consistent patterns of abnormal brain activation in response to emotional stimuli in patients, in particular, decreased amygdala activation. In contrast, brain-level abnormalities in at-risk individuals are more elusive. We address this gap using an image-based meta-analysis of the functional magnetic resonance imaging literature. MethodsFunctional magnetic resonance imaging studies investigating brain responses to negative emotional stimuli and reporting a comparison between at-risk individuals and healthy control subjects were identified. Frequentist and Bayesian voxelwise meta-analyses were performed separately, by implementing a random-effect model with unthresholded group-level T-maps from individual studies as input. ResultsIn total, 17 studies with a cumulative total of 677 at-risk individuals and 805 healthy control subjects were included. Frequentist analyses did not reveal significant differences between at-risk individuals and healthy control subjects. Similar results were observed with Bayesian analyses, which provided strong evidence for the absence of meaningful brain activation differences across the entire brain. Region of interest analyses specifically focusing on the amygdala confirmed the lack of group differences in this region. ConclusionsThese results suggest that brain activation patterns in response to emotional stimuli are unlikely to constitute a reliable endophenotype of schizophrenia. We suggest that future studies instead focus on impaired functional connectivity as an alternative and promising endophenotype.

Mindfulness-based cognitive therapy efficacy in reducing physiological response to emotional stimuli in patients with bipolar I disorder and the intermediate role of cognitive reactivity.

This study aims to investigate the impact of Mindfulness-Based Cognitive Therapy (MBCT) for bipolar disorders on emotional responses by using skin conductance recording, and to investigate a mediating or predictive effect of cognitive reactivity. Sixty-seven patients with bipolar disorder were assessed at baseline, pre-MBCT and post-MBCT. After answering inventories regarding depression and dysfunctional attitudes, they were instructed to focus on emotional pictures from the International Affective Pictures System while electrodermal recording. For a subgroup of patients having a significant change of the electrodermal response, MBCT reduced dysfunctional attitudes and the amplitude of the physiological response to negative stimuli. Findings also show that lower dysfunctional attitudes at baseline predicted a larger reduction of physiological reactivity. MBCT could decrease patient's reactivity to negative stimuli by decreasing its physiological component, which is coherent with its aim to facilitate disengaging from affective stimuli. Further studies are needed to better understand the mechanisms involved and how this could translate in reducing the risk of relapse.

Impaired impulse inhibition of emotional stimuli in patients with borderline personality disorder

This study was aimed to investigate whether BPD patients showed impaired impulse inhibition of emotional and non-emotional stimuli and to explore relevant neuroelectrophysiological mechanisms. A total of 32 BPD patients and 32 matched healthy controls were recruited. Self-reported scales were used to measure psychiatric symptoms. The event-related potentials (ERPs) were recorded when subjects were performing neutral and emotional Stop Signal Task (SST). Group differences in self-reported scores, behavioral variables and ERPs were compared. The BPD group scored significantly higher on impulsivity, severity of BPD symptoms, levels of depression and anxiety than the control group. In neutral SST, no significant group differences were detected in the amplitude and latency of ERPs components induced. In emotional SST, the P2 amplitude of negative emotion was significantly larger than that of neutral emotion in Go trials. In Stop trials, the P2 amplitude of BPD group was significantly smaller than that of control group, and the N2 amplitude of BPD group was significantly greater than that of control group. BPD patients showed impaired inhibition of emotional stimuli rather than non-emotional stimuli. The deficits of emotional impulse control mainly exhibit at the early attention, stimulus evaluation and conflict detection stages.

Microstructural integrity of affective neurocircuitry in patients with dissociative seizures is associated with emotional task performance, illness severity and trauma history

PurposeTo identify variations in white matter tract integrity related to behavioural control in response to emotional stimuli in patients with dissociative seizures (DS) and healthy controls (HC), and examine associations with illness characteristics and psychological trauma history. MethodsTwenty DS patients and 20 HC completed an emotional go/no-go task and questionnaires, and then underwent diffusion tensor imaging (DTI). ResultsPatients had higher false alarm rates in response to negative emotional stimuli than HC. Task performance was correlated with self-reported difficulties in emotional awareness and regulation in everyday life. White matter analysis using tract-based spatial statistics revealed no between-group differences. In patients, fractional anisotropy (FA) in the right uncinate fasciculus, right and left fornix/stria terminalis, and corpus callosum were correlated with task performance. Similar results were found for radial diffusivity (RD), but not mean (MD) or axial diffusivity (AD). In HC, task performance was associated with AD and RD of fewer and smaller clusters in the corpus callosum and right fornix/stria terminalis, and none for FA or MD. Probabilistic tractography of thus identified tracts revealed that mean FA values were correlated with illness parameters (right fornix/stria terminalis with age at onset; posterior corpus callosum with seizure frequency), and psychological trauma history (traumatic experiences during adolescence with anterior corpus callosum). ConclusionsPatients with DS show impaired behavioural control in response to emotional stimuli. Microstructural variations in task-related neurocircuitry show associations with illness parameters and psychological trauma history. Future studies using psychiatric controls should examine the specificity of these findings.

Time course of attention bias in face recognition of patients with depression

Objective To explore the characteristics of cognitive processing over time in recognition of different emotional faces in patients with depression. Methods Totally 29 patients with depression(patient group) and 30 normal control (control group)were selected.Subjects freely viewed positive, sad, threatening and neutral facial stimuli.Eye movement data were collected during the process of watching, and the differences of attention bias in time when the two groups of subjects recognized the four emotional faces were compared.The temporal variation trend of attention between the two groups was analyzed. Results There was no significant difference in the fixation duration between the patient group and the control group in 0-2 s((10.39±1.83)ms, (9.63±1.28)ms), 2-4 s((12.61±2.34)ms, (11.21±3.00)ms), 4-6 s ((12.26±3.11)ms, (10.47±4.06)ms)(all P>0.05). Within 6-8 s((12.64±3.42)ms, (8.90±4.02)ms), 8-10 s((12.55±4.19)ms, (9.36±4.02)ms), the fixation duration in the patient group was significantly longer than that in the control group (P<0.01). The fixation time of the positive faces in the patient group in 0-2 s ((12.07±2.65)ms, (14.50±3.54)ms), 2-4 s((10.69±3.26)ms, (14.66±5.25)ms), 4-6 s((10.11±4.24)ms, (15.43±8.02)ms), 6-8 s((9.39±5.12)ms, (16.88±9.60)ms), 8-10 s ((9.45±4.94)ms, (16.63±10.15)ms) was significantly lower than that in the control group (all P<0.01). Conclusion Patients with depression tend to pay attention to negative stimuli in the later stage of cognitive processing, while the attention to positive stimuli decreases in the early stage of cognitive processing.Cognitive processing of emotional stimuli in patients with depression is manifested as increased attention duration of negative stimuli and decreased attention duration of positive stimuli. Key words: Depression; Attention bias; Face recognition; Eye movement

Endogenous oxytocin response to film scenes of attachment and loss is pronounced in schizophrenia.

BackgroundOxytocin (OXT) is critically involved in the regulation of attachment and interpersonal function. In this study, emotional children’s movies were used to stimulate OXT secretion in patients with schizophrenia and healthy controls (HCs). Furthermore, associations of OXT levels with measures of attachment style (Psychosis Attachment Measure), childhood adversity (Childhood Trauma Questionnaire) and symptom severity [Positive and Negative Syndrome Scale (PANSS)] were considered.MethodsIn 35 patients with schizophrenia and 35 matched HCs, radioimmunoassay with sample extraction was used to determine OXT plasma levels before and after viewing of movie scenes portraying emotional bonding and loss and compared to a non-emotional condition.ResultsStatistical analysis indicated lower baseline OXT levels in female patients than in all other groups. OXT reactivity during emotional movies was significantly higher in patients when compared to HCs. OXT reactivity during the control movie related to PANSS `general psychopathology’. No significant associations appeared between baseline or induced OXT levels and other PANSS subscales, attachment style or childhood adversity in patients.ConclusionsOur findings suggest differences of baseline OXT and a higher OXT reactivity toward strong emotional stimuli in patients with schizophrenia, suggesting a role of OXT as a gender- and context-dependent modulator of socio-emotional function.

Effects of intranasal oxytocin on the attentional bias to emotional stimuli in patients with bulimia nervosa

BackgroundBulimia nervosa (BN) is characterized by binge eating and emotional dysregulation including increased negative affectivity (anger, anxiety). The aim of this study was to examine the effect of oxytocin on attentional processes towards anger in patients with BN. MethodThe study design consisted of a double-blind, placebo-controlled within-subject crossover, single dose experiment. Sixty-four women (31 patients with BN and 33 healthy comparisons) completed self-reported measures to evaluate emotional difficulties and were administered a single dose of intranasal oxytocin (40IU) or placebo followed by a visual probe detection task to examine attentional orienting to angry or happy faces. ResultsPatients with BN reported higher emotional dysregulation and more difficulties in controlling anger compared to the healthy comparison group. Patients with BN and the healthy women exhibited similar attentional bias to angry faces in the placebo condition. Intranasal oxytocin reduced the attentional bias towards angry faces in both the BN patients and the healthy women. ConclusionsWe found that a single dose of oxytocin reduced vigilance towards angry faces in patients with BN as well as healthy women. The results showed that patients with BN are not different from healthy women in terms of vigilance towards threat.

Gait initiation is influenced by emotion processing in Parkinson's disease patients with freezing.

Freezing of gait is a symptom that affects more than 50% of Parkinson's disease (PD) patients and increasing evidence suggests that nonmotor systems (i.e., limbic system) are involved in its underlying mechanisms. The objective of this study was to investigate whether gait initiation characteristics are influenced by emotional stimuli in patients with PD, with or without freezing of gait. A total of 44 participants, divided into 3 groups (15 PD patients with and 15 PD patients without freezing of gait and 14 controls), stood on a sensorized mat and were asked to take a step forward in response to a pleasant image and a step backward in response to an unpleasant one (congruent task, low cognitive load) or to take a step backward in response to a pleasant image and a step forward in response to an unpleasant one (incongruent task, high cognitive load). Reaction time, step size, anticipatory postural adjustments, and sway path were measured. In PD with freezing of gait, the reaction time was longer and the step size was shorter than in the other groups when they took a step forward in response to an unpleasant image (incongruent task). Changes in reaction time performance in response to unpleasant images remained significant after having adjusted for executive dysfunction and positively correlated with the "frequency" of freezing episodes. This study demonstrates that gait initiation was influenced by the emotional valence of visual stimuli in addition to the cognitive load of the task suggesting that the limbic system may be involved in freezing of gait. © 2018 International Parkinson and Movement Disorder Society.

Emotion, working memory, and cognitive control in patients with first-onset and previously untreated minor depressive disorders.

ObjectiveTo explore working memory and the ability to process different emotional stimuli in patients with first-onset and untreated minor (mild or moderate) depression.MethodsPatients with first-onset and previously untreated minor depression, and healthy controls, were enrolled. Using a modified Sternberg working memory paradigm to investigate the combined effects of emotional stimuli with working memory, participants were exposed to experimental stimuli comprising pictures that represented positive, neutral and negative emotions. Working memory ability was measured using reaction time and accuracy, and emotion-processing ability was measured using pupil diameter.ResultsOut of 36 participants (18 patients with minor depression and 18 controls), there were no statistically significant between-group differences in response time and accuracy. Positive stimuli evoked changes in pupil diameter that were significantly smaller in patients with minor depression versus controls, but changes in pupil diameter evoked by negative stimuli were not significantly different between the two groups.ConclusionsHealthy subjects showed a stronger emotional response to positive emotional stimuli than patients with first onset and previously untreated minor depression, but there were no differences in response to negative emotions. There were no statistically significant between-group differences in terms of speed of cognitive response, but this may have been due to the relatively small samples sizes assessed. Studies with larger sample populations are required to further investigate these results.

Blunted brain activation in patients with schizophrenia in response to emotional cognitive inhibition: A functional near-infrared spectroscopy study

IntroductionPatients with schizophrenia (SZ) have deficits of facial emotion processing and cognitive inhibition, but the brain pathophysiology underlying these deficits and their interaction are not clearly understood. We tested brain activity during an emotional face go/no-go task that requires rapid executive control affected by emotional stimuli in patients with SZ using functional near-infrared spectroscopy (fNIRS). MethodsTwenty-five patients with SZ and 28 healthy control subjects were studied. We evaluated behavioral performance and used fNIRS to measure oxygenated hemoglobin concentration changes in fronto-temporal areas during the emotional go/no-go task with emotional and non-emotional blocks. ResultsPatients with SZ made more errors and had longer reaction times in both test blocks compared with healthy subjects. Significantly greater activation in the inferior, superior, middle, and orbital frontal regions were observed in healthy subjects during the emotional go/no-go block compared to the non-emotional go/no-go block, but this difference was not observed in patients with SZ. Relative to healthy subjects, patients with SZ showed less activation in the superior and orbital frontal and middle temporal regions during the emotional go/no-go block. DiscussionOur results suggest that fronto-temporal dysfunction in patients with SZ is due to an interaction between abnormal processing of emotional facial expressions with negative valence and cognitive inhibition, especially during the rapid selection of rule-based associations that override automatic emotional response tendencies. They indicate that fronto-temporal dysfunction is involved in the pathophysiology of emotional–cognitive deficits in patients with SZ.

The relationship between the parameters of cognitive potential P300 and emotional/affective state of patients with chronic pain

To study emotional state and parameters of cognitive evoked potentials (P300) to target emotional stimuli in patients with chronic back pain. A study included 62 patients. Trait and state anxiety was measured using the Spilberger-Khanin questionnaire. Cognitive evoked potentials were investigated. The changes in parameters and topographic distribution of cognitive evoked potentials to target emotional stimuli in patients with chronic back pain with different emotional/affective states were identified. Recording of P300 elicited by emotional stimuli allows to evaluate the characteristics of chronification of pain syndromes.

Executive attention control and emotional responding in attention-deficit/hyperactivity disorder--A functional MRI study.

BackgroundThere are suggestions that patients with attention-deficit/hyperactivity disorder (ADHD) show impairment in executive attention control and emotion regulation. This study investigated emotion regulation as a function of the recruitment of executive attention in patients with ADHD.MethodsThirty-five healthy children/adolescents (mean age = 13.91) and twenty-six children/adolescents with ADHD (mean age = 14.53) participated in this fMRI study. They completed the affective Stroop paradigm viewing positive, neutral and negative images under varying cognitive loads. A 3-way ANOVA (diagnosis-by-condition-by-emotion) was conducted on the BOLD response data. Following this, 2 3-way ANOVAs (diagnosis-by-condition-by-emotion) were applied to context-dependent psychophysiological interaction (gPPI) analyses generated from a dorsomedial frontal cortex and an amygdala seed (identified from the BOLD response ANOVA main effects of condition and emotion respectively).ResultsA diagnosis-by-condition interaction within dorsomedial frontal cortex revealed reduced recruitment of dorsomedial frontal cortex as a function of increased task demands in the children/adolescents with ADHD relative to healthy children/adolescents. The level of reduction in recruitment of dorsomedial frontal cortex was significantly correlated with symptom severity (total and hyperactivity) measured by Conner's Parent Report Scale in the children/adolescents with ADHD. In addition, analysis of gPPI data from a dorsomedial frontal cortex seed revealed significant diagnosis-by-condition interactions within lateral frontal cortex; connectivity between dorsomedial frontal cortex and lateral frontal cortex was reduced in the patients with ADHD relative to comparison youth during congruent and incongruent task trials relative to view trials. There were no interactions of group, or main effect of group, within the amygdala in the BOLD response ANOVA (though children/adolescents with ADHD showed increased responses to positive images within temporal cortical regions during task trials; identified by the diagnosis-by-condition-by-emotion interaction). However, analysis of gPPI data from an amygdala seed revealed decreased connectivity between amygdala and lentiform nucleus in the presence of emotional stimuli in children/adolescents with ADHD (diagnosis-by-emotion interaction).ConclusionThe current study demonstrated disrupted recruitment of regions implicated in executive function and impaired connectivity within those regions in children/adolescents with ADHD. There were also indications of heightened representation of emotional stimuli in patients with ADHD. However, as the findings were specific for positive stimuli, the suggestion of a general failure in emotion regulation in ADHD was not supported.

Facial emotion recognition in schizophrenia: an event-related potentials study.

Previous studies extensively reported an impaired ability to recognize emotional stimuli in patients with schizophrenia. We used pictures from Ekman and Friesen in an event-related potentials study to investigate the neurophysiological correlates of the fear emotional processing compared with happiness in patients with schizophrenia versus healthy subjects. A significant lower P300 amplitude for fear processing but not for P100, N170 and N250 amplitude was found in schizophrenics compared to controls. These data suggest that the ability of basic visual processing is preserved in schizophrenia, whereas facial affect processing is impaired.

Abnormal synchrony and effective connectivity in patients with schizophrenia and auditory hallucinations.

Auditory hallucinations (AH) are the most frequent positive symptoms in patients with schizophrenia. Hallucinations have been related to emotional processing disturbances, altered functional connectivity and effective connectivity deficits. Previously, we observed that, compared to healthy controls, the limbic network responses of patients with auditory hallucinations differed when the subjects were listening to emotionally charged words. We aimed to compare the synchrony patterns and effective connectivity of task-related networks between schizophrenia patients with and without AH and healthy controls.Schizophrenia patients with AH (n = 27) and without AH (n = 14) were compared with healthy participants (n = 31). We examined functional connectivity by analyzing correlations and cross-correlations among previously detected independent component analysis time courses. Granger causality was used to infer the information flow direction in the brain regions.The results demonstrate that the patterns of cortico-cortical functional synchrony differentiated the patients with AH from the patients without AH and from the healthy participants. Additionally, Granger-causal relationships between the networks clearly differentiated the groups. In the patients with AH, the principal causal source was an occipital–cerebellar component, versus a temporal component in the patients without AH and the healthy controls.These data indicate that an anomalous process of neural connectivity exists when patients with AH process emotional auditory stimuli. Additionally, a central role is suggested for the cerebellum in processing emotional stimuli in patients with persistent AH.

Prefrontal activation in response to emotional words in patients with bipolar disorder and major depressive disorder

Abnormal emotional processing is involved in the pathophysiology of bipolar disorder (BD) and major depressive disorder (MDD). However, whether the neural mechanism underlying this deficit is a trait characteristic of BD and MDD is unclear. The aim of this study was to elucidate the similarities and differences in processing of emotional stimuli between patients with BD and MDD in remission, using functional near-infrared spectroscopy (fNIRS). Thirty-two patients (16 with BD and 16 with MDD) and 20 healthy control subjects matched for age, sex, handedness, and years of education were included. An emotional Stroop task, including happy, sad, and threat words, was used. The relative oxygenated and deoxygenated hemoglobin concentration ([oxy-Hb] and [deoxy-Hb]) changes in the frontal region were measured using 52-channels of NIRS. During the threat task, compared to healthy control subjects, patients with BD showed significantly increased [oxy-Hb] in the left inferior frontal region whereas patients with MDD showed significantly increased [oxy-Hb] in the left middle frontal region. During the happy task, compared to healthy control subjects, patients with BD showed significantly decreased [oxy-Hb] in the middle frontal region in both hemispheres. Moreover, patients with BD exhibited decreased [oxy-Hb] and increased [deoxy-Hb] in the superior frontal and middle frontal regions compared to MDD in response to the happy stimulus. No significant differences in [oxy-Hb] or [deoxy-Hb] were seen between the groups during the sad task. These results suggest that abnormal neural responses to emotional stimuli in patients with mood disorders in remission may be a trait characteristic, that negative emotional stimuli are associated with similar prefrontal responses, and that positive emotional stimuli are associated with different prefrontal responses in patients with BD and MDD. These findings indicate that different neural circuits play a role in emotional processing in BD and MDD; this may aid the elucidation of the pathophysiology of these two disorders.

1949 – Implicit learning of cue-picture association with neutral and emotional faces in patients with depression and healthy controls

Knowledge on the brain mechanisms of psychopathology is extremely important for successful treatment of patients. Depression is a group of disorders with varied origins and complex and yet unclear neurobiology. Depressed patients show attentional bias to emotional (especially negative) stimuli. Automatic (implicit) emotional processing in such patients may differ compared to non-depressed controls. We aimed at studying the EEG-correlates of implicit learning with emotional stimuli in patients with depression. 128-channel EEG was recorded in healthy volunteers (12 female and 7 male) and depressed patients (12 female and 7 male), while they performed categorization of pictures as human or animal photographs. Half of the photographs were neutral and half were showing aggressive people or animals. The pictures were preceded by the cue (simple abstract pattern, one for each picture category), which meaning was not explained to the participants. We analyzed visual response to the cue and the CNV recorded during the picture anticipation period (duration was 2s). All participants reported that they did not notice cue-picture association. Unlike the healthy controls, our patients showed strong CNV differences in the right anterior area: larger negativity for the emotional face condition versus the neutral faces. Although our participants were contingency unaware, the cue-picture association was established in our patient group: certain simple neutral pattern was associated with neutral or emotional (aversive) faces, eliciting different CNV during real face anticipation. This may underlie the impairment in depressed patients leading to their fixation on negative emotions.

General emotion processing in social anxiety disorder: Neural issues of cognitive control

Anxiety disorders are characterized by deficient emotion regulation prior to and in anxiety-evoking situations. Patients with social anxiety disorder (SAD) have increased brain activation also during the anticipation and perception of non-specific emotional stimuli pointing to biased general emotion processing. In the current study we addressed the neural correlates of emotion regulation by cognitive control during the anticipation and perception of non-specific emotional stimuli in patients with SAD. Thirty-two patients with SAD underwent functional magnetic resonance imaging during the announced anticipation and perception of emotional stimuli. Half of them were trained and instructed to apply reality-checking as a control strategy, the others anticipated and perceived the stimuli. Reality checking significantly (p<0.01) reduced activity in insular, amygdalar and medial thalamic areas during the anticipation and perception of negative emotional stimuli. The medial prefrontal cortex was comparably active in both groups (p>0.50). The results suggest that cognitive control in patients with SAD influences emotion processing structures, supporting the usefulness of emotion regulation training in the psychotherapy of SAD. In contrast to studies in healthy subjects, cognitive control was not associated with increased activation of prefrontal regions in SAD. This points to possibly disturbed general emotion regulating circuits in SAD.

White-matter abnormalities in the right posterior hemisphere in generalized anxiety disorder: a diffusion imaging study

Prior imaging studies have shown structural, functional and biochemical impairments in patients with generalized anxiety disorder (GAD), particularly in the right hemisphere. In this study we investigated, for the first time to the best of our knowledge, the white-matter microstructure organization in GAD. A total of 12 patients with DSM-IV GAD and 15 matched healthy controls underwent a magnetic resonance imaging session of diffusion weighted imaging, exploring white-matter water molecules by the means of apparent diffusion coefficients (ADCs). Regions of interests were placed in the frontal, parietal, temporal and occipital lobes and in the splenium and genu of the corpus callosum, bilaterally. ADC measures were significantly greater in patients with GAD in the right splenium and right parietal cortex compared with healthy controls (p⩽0.002). No significant correlations between ADCs and age or clinical variables were found. We provide evidence that GAD is associated with disrupted white-matter coherence of posterior right hemisphere regions, which may partly sustain the impaired cognitive regulation of anxiety. Future diffusion imaging investigations are expected to better elucidate the communication between the parietal cortex and other right hemisphere regions in sustaining the cognitive processing of social and emotional stimuli in patients with GAD.