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Aversive social learning experiences might play a significant role in the aetiology of social anxiety disorder. Therefore, we investigated emotional learning and unlearning processes in healthy humans using a social conditioning paradigm. Forty-nine healthy subjects participated in a 2-day fMRI differential conditioning protocol. Acquisition and extinction were conducted on Day 1 and extinction recall on Day 2. BOLD responses, ratings and skin conductance responses were collected. Our data indicate successful conditioning and extinction on the neural and subjective level. As a main result, we observed a positive correlation of social anxiety and conditioning responses on the subjective level (valence and fear) as well as on the neural level with significant CS(+)/CS(-) differentiation in the left amygdala and the left hippocampus. Further, significant CS(+)/CS(-) differentiation in the left amygdala was found during extinction and was associated with lower scores in social anxiety. During extinction recall, we found a tendentially negative correlation of social anxiety and CS(+)/CS(-) differentiation in the vmPFC. In sum, we were able to show that social anxiety is related to conditionability with socially threatening stimuli. This could point to an important aspect in the aetiology of social anxiety disorder.

Absorption represents a disposition to experience altered states of consciousness characterized by intensively focused attention. It is correlated with hypnotic susceptibility and includes phenomena ranging from vivid perceptions and imaginations to mystical experiences. Based on the assumption that drug-induced and naturally occurring mystical experiences share common neural mechanisms, we hypothesized that Absorption is influenced by the T102C polymorphism affecting the 5-HT2a receptor, which is known to be an important target site of hallucinogens like LSD. Based on the pivotal role ascribed to the prefrontal executive control network for absorbed attention and positive symptoms in schizophrenia, it was further hypothesized that Absorption is associated with the VAL158MET polymorphism of the catechol-O-methyltransferase (COMT) gene affecting the dopaminergic neurotransmitter system. The Tellegen Absorption Scale was administered to 336 subjects (95 male, 241 female). Statistical analysis revealed that the group with the T/T genotype of the T102C polymorphism, implying a stronger binding potential of the 5-HT2a receptor, indeed had significantly higher Absorption scores (F = 10.00, P = 0.002), while no main effect was found for the COMT polymorphism. However, the interaction between T102C and COMT genotypes yielded significance (F = 3.89; P = 0.049), underlining the known functional interaction between the 5-HT and the dopaminergic system. These findings point to biological foundations of the personality trait of Absorption.

Global variations of BOLD-fMRI signal are often considered as nuisance effects. This unwanted source of variance is commonly eliminated using proportional global signal scaling (PGSS). However, application of PGSS relies on the assumption that global variations of BOLD signal and experimental conditions are uncorrelated. It has been shown for cognitive tasks that the unjustified application of PGSS might greatly distort statistical results. The present study examined this issue in the domain of emotion research. Specifically, fMRI data were obtained in a block-design, while 21 subjects passively viewed high and low emotionally arousing pleasant, unpleasant, and neutral pictures. Violations of the orthogonality assumption were found for analyses of emotional pictures high in arousal, causing dramatically different outcomes when compared to analyses performed without PGSS. Application of PGSS was associated with attenuated emotional activation in visual cortical areas, insensitivity to emotional activations in limbic and paralimbic regions, and widely distributed artificial deactivations. In contrast, the orthogonality assumption was not violated for low arousing emotional materials. Thus, the validity of using PGSS varied as a function of the emotional arousal of the stimuli. Taken together, the unwarranted use of PGSS might contribute to conflicting results in affective neuroscience fMRI studies, in particular with respect to limbic and paralimbic structures.

The living organism is constantly affected by natural electromagnetic influences covering a wide range of frequencies and amplitudes. One of these natural influences is represented by a phenomenon called atmospherics or sferics. Sferics are very weak electromagnetic impulses generated by atmospheric discharges (lightning). With a newly developed simulation system it was possible to reproduce a previously registered sferics signal and present it to 52 subjects while recording the electroencephalogram (EEG). The repeated application of this stimulus for ten minutes evoked a significant decrease in alpha power in parietal and occipital regions compared to the control condition without sferics presentation. Two constitutional factors were revealed as mediators of sferics effectiveness: the general physical condition of the subjects, and their neuroticism. Individuals with many somatic complaints and a high degree of emotional lability did not respond to the sferics stimulation. This absence of a response is interpreted as an adaptational deficit in reaction to variations in atmospheric parameters.

Cognitive reappraisal and expressive suppression, two major emotion regulation strategies, are differentially related to emotional well-being. The aim of this study was to test the association of individual differences in these two emotion regulation strategies with gray matter volume of brain regions that have been shown to be involved in the regulation of emotions. Based on high-resolution magnetic resonance images of 96 young adults voxel-based morphometry was used to analyze the gray matter volumes of the a priori regions of interest, including amygdala, insula, dorsal anterior cingulate and paracingulate cortex, medial and lateral prefrontal cortex (PFC) and their association with cognitive reappraisal and expressive suppression usage as well as neuroticism. A positive association of cognitive reappraisal with right and tendentially left amygdala volume and of neuroticism with left amygdala volume (marginally significant) was found. Expressive suppression was related to dorsal anterior cingulate/paracingulate cortex and medial PFC gray matter volume. The results of this study emphasize the important role of the amygdala in individual differences in cognitive reappraisal usage as well as neuroticism. Additionally, the association of expressive suppression usage with larger volumes of the medial PFC and dorsal anterior/paracingulate cortex underpins the role of these regions in regulating emotion-expressive behavior.

The misinformation effect refers to memory impairment that arises after exposure to misleading information (Loftus, 2005, p. 361). The present study focuses on the peripheral psychophysiology of false memories induced in a misleading information paradigm. On the basis of Sokolov's orienting reflex and studies concerning the Concealed Information Test (CIT, Lykken, 1959), the main hypothesis assumes differences between true and false memories in terms of the accompanying autonomic measures. It also is assumed that a cued recall of original information preceding the recollection phase reduces misinformation effects. Seventy-five participants watched a video that included nine randomized details. After a ten-minute retention phase, the subjects read a narrative text. Six out of the nine details were replaced by misleading details. Following this, the participants completed a cued recall task for three of the original items. In a subsequent CIT with truthful answering electrodermal responses, phasic heart rate, respiration, and response behavior were measured. Finally, the level of confidence and source monitoring were assessed. The misinformation effect was replicated with newly developed materials in three recollection tasks. Cued recall had no influence on the misinformation effect. Autonomic measures did not differ between true and false memories in the CIT. Electrodermal responses reflected the subjective importance the participants attributed to details in the source monitoring task. Therefore, electrodermal responses are interpreted as a correlate of subjective remembering in a misinformation paradigm.

This article examines the relation between the perception of one's own body position and the distribution of fluid along the subject's spinal (z-) axis. Two experiments are reported. The first one is a replication of the Vaitl et al. study [J. Psychophysiol. 27 (1997) 99] which has shown that changes in shifts of blood volume into or out of the thoracic cavity induced by lower body positive pressure (LBPP: +30 mmHg) or lower body negative pressure (LBNP: -30 mmHg) exerted on the lower body led subjects to feel tilted head-up or head-down, respectively. The second experiment was designed to differentiate between the influence of the otoliths and of the changes in fluid distribution on the perception of body position by means of a sled centrifuge in combination with LBPP and LBNP. In both experiments, changes in blood distribution within the thoracic cavity were measured by impedance plethysmography. Forty healthy volunteers (17 females) participated in experiment 1. They were positioned on the side (right-ear-down head position) on a tiltable board which the subject and the experimenter could tilt via remote control around the subjects' z-axis. Subjects were asked to rotate the board until they felt they were in a horizontal posture. The results clearly show that the perception of posture is influenced by the shift in blood distribution. During LBNP subjects perceived being tilted head-up, whereas LBPP led them feel tilted head-down. Thus, the results obtained in the 1997 study were replicated. Fourteen males volunteered in experiment 2. They were positioned on the sled on a centrifuge in the same manner as in experiment 1. The sled could be moved via remote control by both the subject and the experimenter. While the centrifuge rotated (omega=2 pi times 0.6 rotations per second) the subjects were asked to move the sled until they felt they were in a horizontal position. As in experiment 1, shifts in blood volume were induced by LBPP and LBNP. The distance between the binaural axis (position of the otoliths) and the centrifuge axis served as dependent measure indicating the subjective horizontal position. Due to the additional centrifugal forces exerted on the body the shifts in blood volume were more pronounced than in experiment 1 where only gravitational forces were produced. The changes in the perception of posture were influenced by both the otoliths and the fluid distribution in such a way that both interact in a compensatory manner. These results again corroborate the evidence that afferent inputs from the cardiovascular system play a major role in the perception of the body posture. This phenomenon of graviception needs to be further elucidated with respect to the origins of the afferent inputs and the site and type of graviceptors (mechanoreceptors) involved.

We examined whether males and females differ in the intensity and laterality of their hemodynamic responses towards visual disgust and fear stimuli. Forty-one female, and 51 male subjects viewed disgust-inducing, fear-inducing and neutral pictures in an fMRI block design. Self-report data indicated that the target emotions had been elicited successfully with women responding stronger than men. While viewing the fear pictures, which depicted attacks by humans or animals, men exhibited greater activation in the bilateral amygdala and the left fusiform gyrus than women. This response pattern may reflect greater attention from males to cues of aggression in their environment. Further, the lateralization of brain activation was comparable in the two genders during both aversive picture conditions.

We examined the influence of disgust sensitivity and trait anxiety on disgust processing via functional magnetic resonance imaging. Data of 63 healthy females were combined across four studies, where the same disgusting and affectively neutral pictures had been presented. The disgust pictures, rated as highly repulsive, provoked activation in the occipital cortex, the left prefrontal cortex and both amygdalae. Disgust sensitivity and trait anxiety were positively, and independently from each other, correlated with the activation of the right amygdala. This points to the role of the amygdala as an integrative brain structure, whose activation can be modulated by different affective styles.

This functional magnetic resonance imaging study investigated the disgust- and fear-reactivity of patients suffering from obsessive-compulsive disorder (OCD). Ten OCD patients were scanned while viewing blocks of pictures showing OCD triggers from their personal environment and OCD-irrelevant disgust-inducing, fear-inducing and neutral scenes. Afterwards, the patients rated the intensity of the induced disgust, fear and OCD symptoms. The responses were compared with those of 10 healthy control subjects. The disorder-relevant pictures provoked intense OCD symptoms in the clinical group associated with increased activation in the bilateral prefrontal cortex, the left insula, the right supramarginal gyrus, the left caudate nucleus and the right thalamus. The patients gave higher disgust and fear ratings than the controls for all aversive picture categories. Neural responses towards the disorder-irrelevant disgusting and fear-inducing material included more pronounced insula activation in patients than controls. Summarizing, photos of individual OCD-triggers are an effective means of symptom provocation and activation of the fronto-striato-thalamo-parietal network. The increased insular reactivity of OCD patients during all aversive picture conditions might mirror their susceptibility to experience negative somatic states.

The present functional magnetic resonance imaging study investigated the fear and disgust reactivity of patients suffering from spider phobia. Ten phobics and 13 control subjects were scanned while viewing alternating blocks of phobia-relevant, generally fear-inducing, disgust-inducing and affectively neutral pictures. The patient group rated the spider pictures as being more disgust and fear evoking than the control group, and showed greater activation of the visual association cortex, the amygdalae, the right dorsolateral prefrontal cortex and the right hippocampus. Specific phobia-related activation occurred in the supplementary motor area. The patients also showed greater amygdala activation during the presentation of generally disgust- and fear-inducing pictures. This points to an elevated sensitivity to repulsive and threatening stimuli in spider phobics and implicates the amygdala as a crucial neural substrate.

Cognitive disturbances are common in Parkinson's disease (PD). Examination of cognitive function often reveals deficits in executive functions, including maintenance and inhibition of attention, flexibility in thinking, and planning. The involvement of the dopaminergic system in cognitive executive functions has been suggested by numerous studies. The aim of the present study was to analyze the effect of cognitive training on cognitive performance of PD-patients (N=26). Half of the patients participated in a cognitive training regimen, while the other patients only received standard treatment. The outcome showed improved performance of the group with cognitive treatment in two executive tasks after the training period, while no improvement was seen in the standard-treatment group. The results indicate that specific training is required for improvement of executive functions, while general rehabilitation is not sufficient. Thus, PD-patients might benefit from a short-term cognitive executive function training program that is tailored to the individual patient's needs.

Neurofunctional mechanisms underlying cognitive behavior therapy (CBT) are still not clearly understood. This functional magnetic resonance imaging (fMRI) study focused on changes in brain activation as a result of one-session CBT in patients suffering from spider phobia. Twenty-six female spider phobics and 25 non-phobic subjects were presented with spider pictures, generally disgust-inducing, generally fear-inducing and affectively neutral scenes in an initial fMRI session. Afterwards, the patients were randomly assigned to either a therapy group (TG) or a waiting list group (WG). The scans were repeated one week after the treatment or after a one-week waiting period. Relative to the non-phobic participants, the patients displayed increased activation in the amygdala and the fusiform gyrus as well as decreased activation in the medial orbitofrontal cortex (OFC) during the first exposure. The therapy effect consisted of increased medial OFC activity in the TG relative to the WG. Further, therapy-related reductions in experienced somatic anxiety symptoms were positively correlated with activation decreases in the amygdala and the insula. We conclude that successful treatment of spider phobia is primarily accompanied by functional changes of the medial OFC. This brain region is crucial for the self-regulation of emotions and the relearning of stimulus-reinforcement associations.

The present research addresses the induction of emotion during music listening in adults using categorical and dimensional theories of emotion as background. It further explores the influences of musical preference and absorption trait on induced emotion. Twenty-five excerpts of classical music representing `happiness', `sadness', `fear', `anger' and `peace' were presented individually to 99 adult participants. Participants rated the intensity of felt emotions as well as the pleasantness and arousal induced by each excerpt. Mean intensity ratings of target emotions were highest for 20 out of 25 excerpts. Pleasantness and arousal ratings led to three main clusters within the two-dimensional circumplex space. Preference for classical music significantly influenced specificity and intensity ratings across categories. Absorption trait significantly correlated with arousal ratings only. In sum, instrumental music appears effective for the induction of basic emotions in adult listeners. However, careful screening of participants in terms of their musical preferences should be mandatory.

Disgust extinction is an important mechanism relevant for the treatment of psychiatric disorders. However, only a few studies have investigated disgust extinction. Moreover, because disgust sensitivity (DS) is considered as a relevant factor for learning processes, this study also investigated the potential relationship between DS and disgust extinction learning. The aim of this study was to explore the neuronal correlates of disgust extinction, as well as changes in skin conductance responses (SCRs) and evaluative conditioning. Twenty subjects were exposed to a differential extinction paradigm, in which a previous conditioned, and now unreinforced, stimulus (conditioned stimulus, CS+) was compared to a second stimulus (CS-), which was previously not associated with the unconditioned stimulus (UCS). Extinction learning was measured on three different response levels (BOLD responses, SCRs, and evaluative conditioning). Regarding evaluative conditioning, the CS+ was rated as more unpleasant than the CS-. Interestingly, significantly increased amygdala responses and SCRs toward to the CS- were observed. Finally, a (negative) trend was found between DS scores and BOLD responses of the prefrontal cortex. The present findings showed a dissociation of different response levels. The increased CS- responses could be explained by the assumption that the increased amygdala activity may reflect a safety learning signal during the first extinction trials and the subjective focus may therefore shift from the CS+ to the CS-. The correlation finding supports previous studies postulating that DS hampers extinction processes. The present results point toward dissociations between the response levels in context of extinction processes.

An approach toward detecting hidden knowledge is the Concealed Information Test (CIT). It relies on the memory of crime-relevant information. This study investigated whether its validity is susceptible to memory distortion by misleading information. A misleading information paradigm was employed to distort memory prior to an interrogation with a CIT. Forty-one participants watched a video with specific crime-related information. After a 1-week retention interval, misleading information was introduced. Afterward, a CIT was performed, followed by a threefold memory test. When misleading information was presented, memory performance was reduced, and no physiological response differences between crime-relevant and crime-irrelevant information were found. Without presenting misleading information, physiological responses differed between responses to crime-relevant and crime-irrelevant information. However, responses in all physiological measures also differed between misleading and irrelevant information. The results indicate that the CIT is susceptible to misleading information, which reduces its validity in specific constellations.

The effects of sex and stress hormones on classical fear conditioning have been subject of recent experimental studies. A correlation approach between basal cortisol concentrations and neuronal activation in fear-related structures seems to be a promising alternative approach in order to foster our understanding of how cortisol influences emotional learning. In this functional magnetic resonance imaging study, participants with varying sex hormone status (20 men, 15 women taking oral contraceptives, 15 women tested in the luteal phase) underwent an instructed fear conditioning protocol with geometrical figures as conditioned stimuli and an electrical stimulation as unconditioned stimulus. Salivary cortisol concentrations were measured and afterwards correlated with fear conditioned brain responses. Results revealed a positive correlation between basal cortisol levels and differential activation in the amygdala in men and OC women only. These results suggest that elevated endogenous cortisol levels are associated with enhanced fear anticipation depending on current sex hormone availability.