Peter Weyers

Early cortical processing of natural and artificial emotional faces differs between lower and higher socially anxious persons

Emotional facial expressions provide critical information for social interactions. Above all, angry faces are assumed to reflect potential social threat. We investigated event-related potentials (ERPs) triggered by natural and artificial faces expressing fear, anger, happiness or no emotion in participants with low and high levels of social anxiety. Overall, artificial faces elicited stronger P100 and N170 responses than natural faces. Additionally, the N170 component was larger for emotional compared to neutral facial expressions. Social anxiety was associated with an enhanced emotional modulation of the early posterior negativity (EPN) in response to fearful and angry facial expressions. Additionally, while the late positive potential (LPP) was larger for emotional than for neutral faces in low socially anxious participants, LPPs of higher socially anxious participants did not differ. LPPs might therefore be enhanced in higher socially anxious participants for both emotional and neutral faces. Furthermore, the modulations of the EPN and LPP were comparable between natural and artificial faces. These results indicate that social anxiety influences early perceptual processing of faces and that artificial faces are suitable for psychophysiological emotion research.

The face of fluency: Semantic coherence automatically elicits a specific pattern of facial muscle reactions

This study shows that high conceptual fluency induced by hidden semantic coherence automatically triggers a specific pattern of facial expressions. In the present study, word triads that either had or had not a common remote associate were read by individuals while automatic facial responses were recorded. Although participants were ignorant about the underlying semantic structure, participants’ faces showed an activation of the smiling muscle zygomaticus major (indicating increased positive affect), a relaxation of the frowning muscle corrugator supercilii (indicating decreased negative affect and mental effort), and a relaxation of the forehead muscle frontalis (indicating increased familiarity) after reading coherent compared to incoherent word triads. Implications for intuitive judgements of semantic coherence are discussed.

RELIABILITY AND CONSTRUCT VALIDITY OF THE GERMAN VERSION OF CLONINGER'S TRIDIMENSIONAL PERSONALITY QUESTIONNAIRE

Abstract Cloninger (Psychiatry Development, 3, 167–226, 1986; Archives of General Psychiatry, 44, 573–588, 1987a) postulated a biosocial theory of personality consisting of three independent dimensions. The Tridimensional Personality Questionnaire (TPQ) was developed for the measurement of Novelty Seeking (NS), Harm Avoidance (HA) and Reward Dependence (RD). In this study reliability and construct validity of a German translation of the TPQ were investigated in a sample of 160 subjects. The internal consistencies of the superscales NS, HA and RD were high. The small intercorrelations of the TPQ superscales and the factorial structure of the twelve TPQ subscales yielded some support for Cloningers personality theory. NS seems to tap an impulsivity factor because of strong correlations with Psychoticism, Extraversion, Impulsiveness and Sensation Seeking. HA correlates with Neuroticism and Introversion and appears to measure a neuroticism or behavioral inhibition factor. RD, however, showed only marginal associations with other variables. In general, results for the German version indicate, with exception for the RD scales, sufficient psychometric properties.

Negative stress-coping strategies among novices in surgery correlate with poor virtual laparoscopic performance†‡

This study explored the impact of habitual stress‐coping strategies on the laparoscopic performance of novices in surgery using a virtual reality simulator.

Cortisol reactivity in boys with attention-deficit/hyperactivity disorder and disruptive behavior problems: the impact of callous unemotional traits.

There is a body of literature demonstrating an association between altered hypothalamic pituitary adrenal (HPA) axis reactivity and aggressive behavior. Aggressive and disruptive behavior also is highly prevalent in children with attention deficit/hyperactivity disorder (ADHD). Findings on HPA-axis reactivity in ADHD, however, are rather inconsistent. Specific temperamental risk factors previously were associated with a specific subtype of severe disruptive behavior. These traits might also be characterized by a distinct neurobiological profile across ADHD and disruptive behavior disorders. In this study we focus on psychopathic traits, notably callous unemotional (CU) traits. The main objective of the present study was to investigate whether two groups of ADHD patients with high or low CU traits differed in cortisol reactivity. Subjects were 36 boys with ADHD and disruptive behavior symptoms aged 8 to 14 years. Salivary cortisol probes were taken before and repeatedly after an experimental standardized stress test. Patients scoring high on CU traits showed a blunted HPA axis reactivity to the experimentally induced stress. Results underscore the need to consider specific personality traits in investigating neurobiological correlates in ADHD with disruptive behavior problems.

Validation of the german version of Cloninger's TPQ : Replication and correlations with stress coping, mood measures and drug use

Abstract The tridimensional personality questionnaire (TPQ) was developed by Cloninger (1986, 1987a) to measure the independent personality dimensions Novelty Seeking (NS), Harm Avoidance (HA) and Reward Dependence (RD). After having investigated the basic psychometric properties of a German version of the TPQ in a first study (Weyers et al ., 1995), a new sample of 200 subjects was collected to investigate the reliability of the results of this first study and to add further validity data by including measures of stress coping, mood and drug use. In general, the results of the first study were replicated. The internal consistencies of the superscales NS, HA and RD were high, and a factor analysis of the TPQ subscales yielded some support for Cloningers personality theory. Because of its strong correlations with Psychoticism, Extraversion, Impulsiveness and Sensation Seeking NS seems to tap an impulsivity factor while HA correlates with Neuroticism and Introversion and appears to measure a behavioral inhibition factor, the latter interpretation being supported by correlations between HA and some mood measures like anxiety and self-confidence. In addition, HA showed substantial positive correlations with coping strategies like Rumination, Resignation and Self-pity and substantial negative correlations with strategies like Self-aggrandizement by Comparison with Others and Positive Self-instructions, while the other two TPQ superscales hardly correlate with any of the coping strategies measured. With respect to drug use, only NS showed small but substantial bivariate correlations with the use of nicotine and psychodysleptics for the last 12 weeks and last 2 years. However, a configurational analysis of the TPQ superscales demonstrated that the type II alcoholism pattern proposed by Cloninger (high NS, low HA and low RD) was associated with a strong alcohol consumption.

Brain Activations to Emotional Pictures are Differentially Associated with Valence and Arousal Ratings

Several studies have investigated the neural responses triggered by emotional pictures, but the specificity of the involved structures such as the amygdala or the ventral striatum is still under debate. Furthermore, only few studies examined the association of stimulis valence and arousal and the underlying brain responses. Therefore, we investigated brain responses with functional magnetic resonance imaging of 17 healthy participants to pleasant and unpleasant affective pictures and afterwards assessed ratings of valence and arousal. As expected, unpleasant pictures strongly activated the right and left amygdala, the right hippocampus, and the medial occipital lobe, whereas pleasant pictures elicited significant activations in left occipital regions, and in parts of the medial temporal lobe. The direct comparison of unpleasant and pleasant pictures, which were comparable in arousal clearly indicated stronger amygdala activation in response to the unpleasant pictures. Most important, correlational analyses revealed on the one hand that the arousal of unpleasant pictures was significantly associated with activations in the right amygdala and the left caudate body. On the other hand, valence of pleasant pictures was significantly correlated with activations in the right caudate head, extending to the nucleus accumbens (NAcc) and the left dorsolateral prefrontal cortex. These findings support the notion that the amygdala is primarily involved in processing of unpleasant stimuli, particularly to more arousing unpleasant stimuli. Reward-related structures like the caudate and NAcc primarily respond to pleasant stimuli, the stronger the more positive the valence of these stimuli is.

Abnormal affective responsiveness in attention-deficit/hyperactivity disorder: subtype differences.

BACKGROUND Emotional-motivational dysfunctions likely contribute to attention-deficit/hyperactivity disorder (ADHD), especially to hyperactive and impulsive symptoms. This study examined the affective modulation of the startle reflex in a large sample of ADHD patients. The aim was to compare subtypes of ADHD. METHODS One hundred ninety-seven unmedicated adult ADHD patients (127 combined type [ADHD-C]; 50 inattentive type [ADHD-I]; 20 hyperactive-impulsive type [ADHD-HI]) and 128 healthy control subjects were examined. The affect-modulated startle response as well as valence and arousal ratings were assessed for pleasant, neutral, and unpleasant picture stimuli. RESULTS Control subjects exhibited startle response attenuation and potentiation by pleasant and unpleasant pictures, respectively. In ADHD-HI, startle response was not attenuated by pleasant and not potentiated by unpleasant stimuli. In ADHD-C, startle response was not attenuated by pleasant pictures, and ADHD-I responded similar to control subjects but startle response was attenuated to a lesser degree by pleasant stimuli. The ADHD-HI group rated all pictures as more positive, and male ADHD-HI rated unpleasant stimuli as less arousing. CONCLUSIONS This is the first study to assess the affect-modulated startle response in ADHD. It confirms emotional dysfunctions in these patients; all subtypes showed more or less diminished emotional reactions to pleasant stimuli. The hyperactive-impulsive type was also marked by blunted reactions to unpleasant stimuli. Results suggest that response patterns to emotional cues or reward may help to differentiate ADHD subtypes. Blunted emotional reactivity is especially pronounced in ADHD patients with symptoms of hyperactivity and impulsivity (ADHD-C, ADHD-HI).

Gene–environment interaction influences anxiety-like behavior in ethologically based mouse models

Ethologically based animal models are widely used; however, results from different laboratories vary significantly which may partly be due to the lack of standardization. Here, we examined the effects of circadian rhythm, lighting condition and mouse strain (BALB/c and C57BL/6, known to differ in measures of avoidance and risk assessment behavior) on two well established behavioral tests in mice: the Elevated Plus Maze (EPM) and the Open Field (OF). Parameters from both paradigms are commonly used as indices of anxiety-like behavior. BALB/c mice and C57BL/6 mice were independently tested in the morning and at night, in regular laboratory lighting and in the dark. We developed a novel method based on infrared lighting from below, coupled to respective video-tracking equipment, which facilitates standard testing of behavior interference-free in complete darkness. The two mouse strains differed in anxiety-related variables for the EPM in the dark, and for the OF in regular laboratory lighting. Moreover, BALB/c displayed greater anxiety-like behavior than C57BL/6 in the OF but less anxiety-like behavior than C57BL/6 in the EPM. Lighting condition has a major influence on both behavioral tests and this to a considerably larger extent than circadian rhythm. In addition, the lighting condition interacts strongly with the genetic background, producing discriminative differences in the anxiety-related variables depending on mouse strain and lighting condition. These results challenge the comparability of not sufficiently standardized tests of anxiety-like behavior and emphasize the need for controlling environmental variables in behavioral phenotyping.

Stop looking angry and smile, please: start and stop of the very same facial expression differentially activate threat- and reward-related brain networks

Static pictures of emotional facial expressions have been found to activate brain structures involved in the processing of emotional stimuli. However, in everyday live, emotional expressions are changing rapidly, and the processing of the onset vs the offset of the very same emotional expression might rely on different brain networks, presumably leading to different behavioral and physiological reactions (e.g. approach or avoidance). Using functional magnetic resonance imaging, this was examined by presenting video clips depicting onsets and offsets of happy and angry facial expressions. Subjective valence and threat ratings clearly depended on the direction of change. Blood oxygen level dependent responses indicate both reward- and threat-related activations for the offset of angry expressions. Comparing onsets and offsets, angry offsets were associated with stronger ventral striatum activation than angry onsets. Additionally, the offset of happy and the onset of angry expressions showed strong common activity in the lateral orbitofrontal cortex bilaterally, the left amygdala and the left insula, whereas the onset of happy and the offset of angry expressions induced significant activation in the left dorsal striatum. In sum, the results confirm different activity in motivation-related brain areas in response to the onset and offset of the same emotional expression and highlight the importance of temporal characteristics of facial expressions for social communication.