Albert Wabnegger

Effects of personal space intrusion in affective contexts: an fMRI investigation with women suffering from borderline personality disorder

The amygdala and the parietal cortex play a key role in the neural representation of personal space. Although the concept of personal space is clinically very relevant for borderline personality disorder (BPD), especially in affective contexts, it has not been investigated thus far with functional magnetic resonance imaging (fMRI). In this fMRI study, 25 female BPD patients and 25 healthy women were exposed to photos of angry, disgusted and neutral facial expressions. All stimuli were once shown as still photos, and once were zoomed-in in order to simulate intrusion into ones own personal space. Approaching faces generally provoked activation of the amygdala and the somatosensory cortex. BPD patients showed an increased activation within both regions, but only toward approaching disgusted faces. Their amygdala activation in this specific condition positively correlated with self-disgust scores. Moreover, the clinical group indicated an enhanced personal distance preference, which was associated with parietal activation. The present study revealed altered personal space processing of BPD patients, especially in situations that relate to social contexts involving disgust. Future studies should focus on the temporal stability of personal space processing during the natural course of BPD as well as during therapy.

Facial Emotion Recognition in Parkinson's Disease: An fMRI Investigation

Background Findings of behavioral studies on facial emotion recognition in Parkinson’s disease (PD) are very heterogeneous. Therefore, the present investigation additionally used functional magnetic resonance imaging (fMRI) in order to compare brain activation during emotion perception between PD patients and healthy controls. Methods and Findings We included 17 nonmedicated, nondemented PD patients suffering from mild to moderate symptoms and 22 healthy controls. The participants were shown pictures of facial expressions depicting disgust, fear, sadness, and anger and they answered scales for the assessment of affective traits. The patients did not report lowered intensities for the displayed target emotions, and showed a comparable rating accuracy as the control participants. The questionnaire scores did not differ between patients and controls. The fMRI data showed similar activation in both groups except for a generally stronger recruitment of somatosensory regions in the patients. Conclusions Since somatosensory cortices are involved in the simulation of an observed emotion, which constitutes an important mechanism for emotion recognition, future studies should focus on activation changes within this region during the course of disease.

Altered cerebellar-amygdala connectivity in violent offenders: A resting-state fMRI study.

It has repeatedly been reported, that there are differences in grey matter volume (GMV) between violent offenders and non-violent controls. However, it remains unclear, if structural brain abnormalities influence resting-state functional connectivity (RS-fc) between brain regions. Therefore, in the present investigation, 31 male high-risk violent prisoners were compared to 30 non-criminal controls with respect to RS-fc between brain areas. Seed regions for resting-state analysis were selected based on GMV differences between the two groups. Overall, inmates had more GMV in the cerebellum than controls and revealed higher RS-fc between the cerebellum and the amygdala. In contrast, controls relative to prisoners showed higher RS-fc between the cerebellum and the orbitofrontal cortex (OFC). In addition, controls showed more GMV in the dorsolateral prefrontal cortex (DLPFC). Inmates relative to controls had higher RS-fc within the DLPFC. Results are discussed with respect to cerebellar contributions to a brain network underlying moral behavior and violence. Enhanced cerebellar-amygdala connectivity in violent offenders might reflect alterations in the processing of moral emotions. Heightened functional connectivity between cerebellar hemispheres and the OFC in controls could be a correlate of enhanced emotion regulation capacities. Higher functional intra-DLPFC connectivity in violent offenders might represent an effort to regulate emotions.

Intact emotion recognition and experience but dysfunctional emotion regulation in idiopathic Parkinson's disease

BACKGROUND A specific non-motor impairment in Parkinsons disease (PD) concerns difficulties to accurately identify facial emotions. Findings are numerous but very inconsistent, ranging from general discrimination deficits to problems for specific emotions up to no impairment at all. By contrast, only a few studies exist about emotion experience, altered affective traits and states in PD. OBJECTIVE To investigate the decoding capacity for affective facial expressions, affective experience of emotion-eliciting images and affective personality traits in PD. METHODS The study sample included 25 patients with mild to moderate symptom intensity and 25 healthy controls (HC) of both sexes. The participants were shown pictures of facial expressions depicting disgust, fear, and anger as well as disgusting and fear-relevant scenes. Additionally, they answered self-report scales for the assessment of affective traits. RESULTS PD patients had more problems in controlling anger and disgust feelings than HC. Higher disgust sensitivity in PD was associated with lower functioning in everyday life and lower capacity to recognize angry faces. Furthermore, patients reported less disgust towards poor hygiene and spoiled food and they stated elevated anxiety. However, the clinical group displayed intact facial emotion decoding and emotion experience. Everyday life functionality was lowered in PD and decreased with stronger motor impairment. Furthermore, disease duration was negatively associated to correct classification of angry faces. CONCLUSIONS Our data indicate that problems with emotion regulation may appear already in earlier disease stages of PD. By contrast, PD patients showed appropriate emotion recognition and experience. However, data also point to a deterioration of emotion recognition capacity with the course of the disease. Compensatory mechanisms in PD patients with less advanced disease are discussed.

Do not think about pain: Neural correlates of attention guiding during visual symptom provocation in dental phobia—An fMRI study

Patients undergoing dental treatment employ different attentional strategies. In order to investigate associated neuronal correlates, we exposed 20 women suffering from dental phobia and 20 non-anxious women to disorder-related and unrelated pictures. They were asked to either direct their attention to a foreground stimulus in the image (distraction), to classify the content, or to judge whether the picture elicited fear of pain. The patients rated the majority of dental pictures as pain-relevant (84%) in contrast to the control group (12%). Observed group differences were restricted to the pain condition with enhanced orbitofrontal cortex (OFC) activation displayed by the patients. For the controls, OFC and amygdala activity were positively correlated with self-reported dental anxiety during attention to pain. Across both groups, pain focusing provoked increased amygdala recruitment. As the OFC and amygdala are central for the evaluation of threat signals, the mere thinking about the possible pain relevance of stimuli seems to be dysfunctional.

Experience of negative emotions in Parkinson's disease: An fMRI investigation.

Objective Amygdala abnormalities have been discussed as a possible mechanism underlying reduced reactivity to negative stimuli in Parkinson’s disease (PD). Methods The present investigation used functional magnetic resonance imaging (fMRI) in order to test this hypothesis. We compared brain activation of 17 nondepressed and nondemented PD patients with 22 healthy controls during the elicitation of negative affective states. The patients suffered from moderate motor symptoms for an average of 75 months and had stopped their antiparkinson medication 10–12 h prior to the fMRI testing. All participants were shown images which depicted disgusting, fear-relevant and neutral contents and they answered self-report scales for the assessment of disgust proneness and trait anxiety. Results Both groups did not differ from each other in affective state and trait ratings. In line with the self-report, the fMRI data showed similar activation (including the amygdala) in both groups during disgust and fear elicitation. Conclusion This fMRI investigation found no indication of diminished disgust and fear experience in PD. Significance: Previously reported affective processing deficits in PD might be due to insufficiently controlled confounding variables (medication, depression, cognitive impairment).

Brain abnormalities in high-risk violent offenders and their association with psychopathic traits and criminal recidivism

Measures of psychopathy have been proved to be valuable for risk assessment in violent criminals. However, the neuronal basis of psychopathy and its contribution to the prediction of criminal recidivism is still poorly understood. We compared structural imaging data from 40 male high-risk violent offenders and 37 non-delinquent healthy controls via voxel-based morphometry. Psychopathic traits and risk of violence recidivism were correlated with gray matter volume (GMV) of regions of interest previously shown relevant for criminal behavior. Relative to controls, criminals showed less GMV in the prefrontal cortex (PFC) and more GMV in cerebellar regions and basal ganglia structures. Within criminals, we found a negative correlation between prefrontal GMV and psychopathy. Additionally, there was a positive correlation between cerebellar GMV and psychopathy as well as risk of recidivism for violence. Moreover, GMVs of the basal ganglia and supplementary motor area (SMA) were positively correlated with anti-sociality. GMV of the amygdala was negatively correlated with dynamic risk for violence recidivism. In contrast, GMV of (para)limbic areas (orbitofrontal cortex, insula) was positively correlated with anti-sociality and risk of violence recidivism. The current investigation revealed that in violent offenders deviations in GMV of the PFC as well as areas involved in the motor component of impulse control (cerebellum, basal ganglia, SMA) are differentially related to psychopathic traits and the risk of violence recidivism. The results might be valuable for improving existing risk assessment tools.

Role of Disgust Proneness in Parkinson’s Disease: A Voxel-Based Morphometry Study

The knowledge about personality traits in Parkinsons disease (PD) is still limited. In particular, disgust proneness has not been investigated as well as its neuronal correlates. Although several morphometric studies demonstrated that PD is associated with gray matter volume (GMV) reduction in olfactory and gustatory regions involved in disgust processing, a possible correlation with disgust proneness has not been investigated. We conducted a voxel-based morphometry analysis to compare GMV between 16 cognitively normal male PD patients with mild to moderate symptoms and 24 matched control subjects. All participants had answered questionnaires for the assessment of disgust proneness, trait anger and trait anxiety. We correlated questionnaire scores with GMV in both groups. The clinical group reported selectively reduced disgust proneness toward olfactory stimuli associated with spoilage. Moreover, they showed GMV reduction in the central olfactory system [orbitofrontal cortex (OFC) and piriform cortex]. Disgust items referring to olfactory processing were positively correlated with OFC volume in PD patients. Our data suggest an association between PD-associated neurodegeneration and olfactory related facets of the personality trait disgust proneness.

Neuronal correlates of personal space intrusion in violent offenders.

Personal space (PS) is defined as the imagery region immediately surrounding our body, which acts as safety zone. It has been suggested that PS is enlarged in violent offenders and that this group shows an enhanced sensitivity to the reduction of interpersonal distance. In the present fMRI study high-risk violent offenders and noncriminal controls were presented with photos of neutral facial expressions by men and women. All images were shown twice, as static photos, and animated (i.e., appearing to approach the subject) in order to simulate PS intrusion. Approaching faces generally provoked activation of a fronto-parietal network and the insula. Offenders responded with greater insula activation to approaching faces, especially when the person was male. Insular activation has been recognized before as a neuronal correlate of potential threat and harm detection in PS. The increased reactivity of violent offenders is possibly a result of their hostile attribution bias.

Emotion-specific nocebo effects: an fMRI study

The neurobiological mechanisms of nocebos are still poorly understood. Thirty-eight women participated in a ‘smell study’ using functional magnetic resonance imaging. They were presented with an odorless stimulus (distilled water) together with the verbal suggestion that this fluid has an aversive odor which enhances disgust feelings. The nocebo was presented while the participants viewed disgusting, fear-inducing, and neutral images. Participants’ affective and neuronal responses during nocebo administration were compared with those in a control condition without nocebo. Twenty-nine women (76%) reported perceiving a slightly unpleasant and arousing odor. These ‘nocebo responders’ experienced increased disgust during the presentation of disgusting images in combination with the nocebo and showed enhanced left orbitofrontal cortex (OFC) activation. It has been suggested that the OFC is involved in the generation of placebo/nocebo-related expectations and appraisals. This region showed increased functional connectivity with areas involved in interoception (insula), autobiographical memories (hippocampus), and odor imagery (piriform cortex) during nocebo administration. The nocebo-induced change in brain activation was restricted to the disgust condition. Implications for psychotherapy are discussed.