Face processing is enhanced in the left and upper visual hemi-fields

We tested whether two known hemi-field asymmetries would affect visual search with face stimuli. Holistic processing of spatial configurations is better in the left hemi-field, reflecting a right hemisphere specialization, and object recognition is better in the upper visual field, reflecting stronger projections into the ventral stream. Faces tap into holistic processing and object recognition at the same time, which predicts better performance in the left and upper hemi-field, respectively. In the first experiment, participants had to detect a face with a gaze direction different from the remaining faces. Participants were faster to respond when targets were presented in the left and upper hemi-field. The same pattern of results was observed when only the eye region was presented. In the second experiment, we turned the faces upside-down, which eliminated the typical spatial configuration of faces. The left hemi-field advantage disappeared, showing that it is related to holistic processing of faces, whereas the upper hemi-field advantage related to object recognition persisted. Finally, we made the search task easier by asking observers to search for a face with open among closed eyes or vice versa. The easy search task eliminated the need for complex object recognition and, accordingly, the advantage of the upper visual field disappeared. Similarly, the left hemi-field advantage was attenuated. In sum, our findings show that both horizontal and vertical asymmetries affect the search for faces and can be selectively suppressed by changing characteristics of the stimuli.     

Phenotypes of sleeplessness: stressing the need for psychodiagnostics in the assessment of insomnia

Insomnia is a too general term for various subtypes that might have different etiologies and therefore require different types of treatment. In this explorative study we used cluster analysis to distinguish different phenotypes in 218 patients with insomnia, taking into account several factors including sleep variables and characteristics related to personality and psychiatric comorbidity. Three clusters emerged from the analysis. The ‘moderate insomnia with low psychopathology’-cluster was characterized by relatively normal personality traits, as well as normal levels of anxiety and depressive symptoms in the presence of moderate insomnia severity. The ‘severe insomnia with moderate psychopathology’-cluster showed relatively high scores on the Insomnia Severity Index and scores on the sleep log that were indicative for severe insomnia. Anxiety and depressive symptoms were slightly above the cut-off and they were characterized by below average self-sufficiency and less goal-directed behavior. The ‘early onset insomnia with high psychopathology’-cluster showed a much younger age and earlier insomnia onset than the other two groups. Anxiety and depressive symptoms were well above the cut-off score and the group consisted of a higher percentage of subjects with comorbid psychiatric disorders. This cluster showed a ‘typical psychiatric’ personality profile. Our findings stress the need for psychodiagnostic procedures next to a sleep-related diagnostic approach, especially in the younger insomnia patients. Specific treatment suggestions are given based on the three phenotypes.     

Individual classification of elementary school children’s physical activity: A time-efficient,group-based approach to reference measurements

The objective measurement of physical activity using accelerometers is becoming increasingly popular. There is little consensus, however, about how to analyze acceleration data. One promising approach is the use of reference measurements in which the subjects conduct specific activities. This makes it possible to identify data patterns that indicate these activities for each subject. The drawback of this approach is its rather high cost, in terms of both time and money. We propose a new approach in which a group of children conduct the reference measurements at the same time. We trained support vector machine models on the accelerometer data of 70 children (ages 8–11 years) to predict their activities during those reference measurements. We correctly classified activities with an accuracy of 96.9 % when fitting the individual models for each subject, and 87.5 % when fitting general models for all subjects. The obtained accuracies were comparable to results reported in previous reference measurement studies, in which each subject was measured individually. They were higher than the accuracies obtained by the traditional approach, which transfers accelerometer data to counts and classifies those on the basis of predefined cut points. We concluded that our approach can yield a valuable contribution, particularly to studies with larger samples.     

Simultaneous and sequential Feature Negative discriminations: Elemental learning and occasion setting in human Pavlovian conditioning

Using a conditioned suppression task, we investigated simultaneous (XA−/A+) vs. sequential (X → A−/A+) Feature Negative (FN) discrimination learning in humans. We expected the simultaneous discrimination to result in X (or alternatively the XA configuration) becoming an inhibitor acting directly on the US, and the sequential discrimination in X becoming a negative occasion setter acting indirectly on the A-US link. After simultaneous FN training, X+ training completely abolished discriminative XA/A responding (Experiment 1), and X transferred inhibition to new targets B regardless of their training history (B+ or YB−/B+) (Experiment 2), suggesting X became a simple inhibitor. After sequential FN training, X showed the predicted selective transfer to a target B that also had been modulated (Y → B−/B+), not to a simple excitor (B+) (Experiment 4), but turning X into an excitor (X+) likewise disrupted discriminative X → A/A responding (Experiment 3). This suggests that X acquired a combination of modulatory and direct inhibitory properties, and that the joint contribution of both components is necessary for the suppression of the target-induced US activation.     

Category priming with aliens: analysing the influence of targets' prototypicality on the centre surround inhibition mechanism

Marginally perceptible prototypes as primes lead to slowed reactions to related category exemplars as compared to unrelated ones. This at first glance counterintuitive finding has been interpreted as evidence for a particular mechanism of lateral inhibition, namely the centre surround inhibition mechanism. We investigated the semantic surround of category labels by experimentally manipulating the prototypicality of stimuli. Participants first learned two new categories of fantasy creatures in a 5-day-long learning phase before they worked through a semantic priming task with the category prototypes as primes and category exemplars as targets. For high-prototypical targets we observed benefit effects from related primes, whereas for low-prototypical targets we observed cost effects. The results define when the centre surround inhibition mechanism is applied, and furthermore might explain why previous studies with word stimuli (i.e., material that prevents experimental manipulation of prototypicality) observed mixed results concerning the prototypicality of targets.     

Young men's coping with androgenetic alopecia: acceptance counts when hair gets thinner

The present study examined how young men cope with balding (androgenetic alopecia). The sample consisted of 160 university students (18–30 years) with varying degrees of hair loss (stages II–VII on the Norwood–Hamilton Scale). Three ways of coping were distinguished: compensation, avoidance, and acceptance. Psychological distress due to hair loss depended neither on the age of participants nor on the stage of balding. Since compensation and avoidance were associated with high levels of distress, their functional value might be questioned. Acceptance, however, was negatively related to distress – even, or rather, especially when stage of hair loss was advanced. Furthermore, acceptance had a direct negative effect on medical consultation about hair loss. By contrast, compensation and avoidance had a positive distress-mediated effect on medical consultation. Taken together, this study underlines the adaptive role of acceptance when confronted with irreversible changes such as androgenetic alopecia.     

Impaired emotion recognition in music in Parkinson’s disease

Music has the potential to evoke strong emotions and plays a significant role in the lives of many people. Music might therefore be an ideal medium to assess emotion recognition. We investigated emotion recognition in music in 20 patients with idiopathic Parkinson’s disease (PD) and 20 matched healthy volunteers. The role of cognitive dysfunction and other disease characteristics in emotion recognition was also evaluated.     

Nature and facts about natural and artifactual categories: Sex differences in the semantic priming paradigm

There is abundant evidence from behavioral and neurophysiological experiments for the distinction of natural versus artifactual categories and a gender-specific difference: women’s performances in cognitive tasks increase when natural categories are used, whereas men’s performances increase with artifactual categories. Here, we used the semantic priming paradigm to study retrieval processes by presenting category labels as primes and exemplars as targets. Overall, in two experiments we found larger priming effects for natural than for artifactual categories. In addition, females showed positive priming effects for natural but negative effects for artifactual categories, whereas males showed positive priming effects for both categories. This pattern matches with that from other tasks and can be interpreted as evidence that the findings from these other tasks are, at least partially, indeed due to different representations or processing modes for males and females and not (exclusively) due to—for example—different familiarity with a category. In a further experiment, we showed that the found pattern for females can be manipulated by focusing on perceptual vs. functional features. The results can be interpreted as first evidence that there are (eventually in addition to different “crystallized” semantic structures) specific default processing modes that differ for males and females.     

Center-surround or spreading inhibition: which mechanism caused the negative effect from repeated masked semantic primes?

In the paradigm of repeated masked semantic priming (Wentura & Frings. 2005), prime and mask are repeatedly and rapidly interchanged. Using this technique in a semantic priming task with category labels as primes and category exemplars as targets (related, e.g.. BIRD - swan --> BIRD - finch; unrelated, e.g., BIRD - lily --> FRUIT - finch), Wentura and Frings found a negatively signed priming effect. Here we used the repeated masking technique with category exemplars as targets and primes (i.e., identity priming) for analyzing, whether this effect reflects center-surround or spreading inhibition. If the repeated masked technique reflects spreading inhibition, a negative effect should also appear for identity priming. In contrast, a center-surround approach would predict a positive effect. In accordance with the latter hypothesis, we found a significant positive effect in identity priming (Experiment 1a) and significant difference to the negatively signed semantic priming effect when primes were category labels (Experiment 1b). This is indicative of the repeated masked semantic priming effect being a negatively signed semantic priming effect due to a center-surround mechanism.