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Standard diagnostic procedures for assessing temporal-processing abilities of adult patients with aphasia have so far not been developed. In our study, temporal-order measurements were conducted using two different experimental procedures to identify a suitable measure for clinical studies. Additionally, phoneme-discrimination abilities were tested on the word, as well as on the sentence level, as a relationship between temporal processing and phoneme-discrimination abilities is assumed. Patients with aphasia displayed significantly higher temporal-order thresholds than control subjects. The detection of an association between temporal processing and speech processing, however, depended on the stimuli and the phoneme-discrimination tasks used. Our results also suggest top-down feedback on phonemic processing.

Two correlates of outcome processing in the orbitofrontal cortex (OFC) have been proposed in the literature: One hypothesis suggests that the lateral/medial division relates to representation of outcome valence (negative vs. positive), and the other suggests that the medial OFC maintains steady stimulus-outcome associations, whereas the lateral OFC represents changing (unsteady) outcomes to prepare for response shifts. These two hypotheses were contrasted by comparing the original with the inverted version of the Iowa Gambling Task in an event-related functional magnetic resonance imaging experiment. Results showed (1) that (caudo) lateral OFC was indeed sensitive to the steadiness of the outcomes and not merely to outcome valence and (2) that the original and the inverted tasks, although both designed to measure sensitivity for future outcomes, were not equivalent as they enacted different behaviors and brain activation patterns. Results are interpreted in terms of Kahneman and Tversky's prospect theory suggesting that cognitions and decisions are biased differentially when probabilistic future rewards are weighed against consistent punishments relative to the opposite scenario [Kahneman, D., & Tversky, A. Choices, values, and frames. American Psychologist, 39, 341-350, 1984]. Specialized processing of unsteady rewards (involving caudolateral OFC) may have developed during evolution in support of goal-related thinking, prospective planning, and problem solving.

Priming tasks are used for investigating the deficits of selective attention in schizophrenia, which are thought to be related to the psychotic symptoms. Priming was assessed in acutely psychotic unmedicated (n = 22) and medicated (n = 36) schizophrenia patients and in control subjects (n = 42). The subjects had to indicate the location of a target stimulus in two consecutive stimulus displays (prime and probe). Each stimulus appeared together with a distractor on a screen. Negative Priming is characterized by an increase in reaction time, whenever a probe target is presented at a prime distractor location. Positive Priming is characterized by a decrease in reaction time, when the probe target is presented at the prime target location. Schizophrenia patients altogether showed no abnormalities in priming effects, neither in the acute phase of illness (medicated and unmedicated) nor in partial remission (one month later, medicated). In unmedicated patients however Negative Priming was inversely correlated with the severity of positive symptoms. This indicates a priming deficit in a small subgroup of severely ill patients. The data support the notion that automatic (implicit) mechanisms of learning are unimpaired in schizophrenia patients unless symptoms exceed a certain critical level.

Cognitive deficits affecting memory, attention and speed of information processing are common in multiple sclerosis (MS). The mechanisms of cognitive impairment remain unclear. Here, we examined the association between neuropsychological test performance and brain atrophy in a group of mildly disabled patients with relapsing-remitting MS. We applied voxel-based morphometry (SPM2) to investigate the distribution of brain atrophy in relation to cognitive performance. Patients had lower scores than control subjects on tests of memory and executive function, including the PASAT, Digit Span Backward and a test of short-term verbal memory (Memo). Among patients, but not healthy controls, performance on the PASAT, a comprehensive measure of cognitive function and reference task for the cognitive evaluation of MS-patients, correlated with global grey matter volume as well as with grey matter volume in regions associated with working memory and executive function, including bilateral prefrontal cortex, precentral gyrus and superior parietal cortex as well as right cerebellum. Compared to healthy subjects, patients showed a volume reduction in left temporal and prefrontal cortex, recently identified as areas predominantly affected by diffuse brain atrophy in MS. A comparison of low performers in the patient group with their matched control subjects showed more extensive and bilateral temporal and frontal volume reductions as well as bilateral parietal volume loss, compatible with the progression of atrophy found in more advanced MS-patients. These findings indicate that MS-related deficits in cognition are closely associated with cortical atrophy.

To determine the relative safety of onboard display positions while driving, participants performed a lane-keeping task in a driving simulator. Concurrently, they reacted to a light by pushing the brake pedal. A secondary task was projected onto a display at one of the seven different locations in the cockpit. Behavioral data, eye movements, and subjective rating scales showed that the manipulation of display information during driving disturbed drivers' performance exponentially as a function of distance between the line of sight to the outside primary task and the onboard display position. Vertical eccentricity had a greater detrimental effect than horizontal distance. Under a certain condition with a high secondary task load, reaction time of pushing the brake to the outside stimulus nearly doubled with a diagonal eccentricity of 35 degrees as compared to lower eccentricities. Subjective workload measures complement the behavioral data of clear detrimental effects with eccentricities of at least 35 degrees .

Findings from several functional magnetic resonance imaging (fMRI) studies implicate the existence of a distinct neural disgust substrate, whereas others support the idea of distributed and integrative brain systems involved in emotional processing. In the present fMRI experiment 12 healthy females viewed pictures from four emotion categories. Two categories were disgust-relevant and depicted contamination or mutilation. The other scenes showed attacks (fear) or were affectively neutral. The two types of disgust elicitors received comparable ratings for disgust, fear and arousal. Both were associated with activation of the occipitotemporal cortex, the amygdala, and the orbitofrontal cortex; insula activity was nonsignificant in the two disgust conditions. Mutilation scenes induced greater inferior parietal activity than contamination scenes, which might mirror their greater capacity to capture attention. Our results are in disagreement with the idea of selective disgust processing at the insula. They point to a network of brain regions involved in the decoding of stimulus salience and the regulation of attention.

Meditation experiences evolve along a spectrum, ranging from an effortful struggle with the technique to deep transpersonal states where all dualities dissolve. The present study investigated to what extent the depth of meditation is influenced by the amount of meditation practice and the personality trait of absorption, and whether deep experiences influence the mindfulness of meditators in everyday life. A set of questionnaires (Meditation Depth Questionnaire, Tellegen Absorption Scale, and Freiburg Mindfulness Inventory) was distributed to meditators (N = 251) practicing different techniques. A structural equation modeling analysis revealed that absorption exerted a stronger influence on meditation depth (path coefficient: .48) than the amount of meditation practice (path coefficient: .21). Mindfulness was strongly influenced by meditation depth (path coefficient: .42) and moderately by absorption (path coefficient: .21). These complex relations between practice, personality, meditation experiences, and everyday behavior should be considered in future research on transpersonal states induced by meditation. (PsycINFO Database Record (c) 2019 APA, all rights reserved)

Humans show large differences in the preferred timing of their sleep and activity. This so-called "chronotype" is largely regulated by the circadian clock. Both genetic variations in clock genes and environmental influences contribute to the distribution of chronotypes in a given population, ranging from extreme early types to extreme late types with the majority falling between these extremes. Social (e.g., school and work) schedules interfere considerably with individual sleep preferences in the majority of the population. Late chronotypes show the largest differences in sleep timing between work and free days leading to a considerable sleep debt on work days, for which they compensate on free days. The discrepancy between work and free days, between social and biological time, can be described as 'social jetlag.' Here, we explore how sleep quality and psychological wellbeing are associated with individual chronotype and/or social jetlag. A total of 501 volunteers filled out the Munich ChronoType Questionnaire (MCTQ) as well as additional questionnaires on: (i) sleep quality (SF-A), (ii) current psychological wellbeing (Basler Befindlichkeitsbogen), (iii) retrospective psychological wellbeing over the past week (POMS), and (iv) consumption of stimulants (e.g., caffeine, nicotine, and alcohol). Associations of chronotype, wellbeing, and stimulant consumption are strongest in teenagers and young adults up to age 25 yrs. The most striking correlation exists between chronotype and smoking, which is significantly higher in late chronotypes of all ages (except for those in retirement). We show these correlations are most probably a consequence of social jetlag, i.e., the discrepancies between social and biological timing rather than a simple association to different chronotypes. Our results strongly suggest that work (and school) schedules should be adapted to chronotype whenever possible.

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.

The aim of this fMRI study was to explore brain structures that are involved in the processing of erotic and disgust-inducing pictures. The stimuli were chosen to trigger approach and withdrawal tendencies, respectively. By adding sadomasochistic (SM) scenes to the design and examining 12 subjects with and 12 subjects without sadomasochistic preferences, we introduced a picture category that induced erotic pleasure in one sample and disgust in the other sample. Since we also presented neutral pictures, all subjects viewed pictures of four different categories: neutral, disgust-inducing, erotic, and SM erotic pictures. The analysis indicated that several brain structures are commonly involved in the processing of disgust-inducing and erotic pictures (occipital cortex, hippocampus, thalamus, and the amygdala). The ventral striatum was specifically activated when subjects saw highly sexually arousing pictures. This indicates the involvement of the human reward system during the processing of visual erotica.

The aim of this fMRI study was to explore brain structures that are involved in the processing of erotic and disgust-inducing pictures. The stimuli were chosen to trigger approach and withdrawal tendencies, respectively. By adding sadomasochistic (SM) scenes to the design and examining 12 subjects with and 12 subjects without sadomasochistic preferences, we introduced a picture category that induced erotic pleasure in one sample and disgust in the other sample. Since we also presented neutral pictures, all subjects viewed pictures of four different categories: neutral, disgust-inducing, erotic, and SM erotic pictures. The analysis indicated that several brain structures are commonly involved in the processing of disgust-inducing and erotic pictures (occipital cortex, hippocampus, thalamus, and the amygdala). The ventral striatum was specifically activated when subjects saw highly sexually arousing pictures. This indicates the involvement of the human reward system during the processing of visual erotica.

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.