Elke van der Meer

Individual differences in moral judgment competence influence neural correlates of socio-normative judgments

To investigate how individual differences in moral judgment competence are reflected in the human brain, we used event-related functional magnetic resonance imaging, while 23 participants made either socio-normative or grammatical judgments. Participants with lower moral judgment competence recruited the left ventromedial prefrontal cortex and the left posterior superior temporal sulcus more than participants with greater competence in this domain when identifying social norm violations. Moreover, moral judgment competence scores were inversely correlated with activity in the right dorsolateral prefrontal cortex (DLPFC) during socio-normative relative to grammatical judgments. Greater activity in right DLPFC in participants with lower moral judgment competence indicates increased recruitment of rule-based knowledge and its controlled application during socio-normative judgments. These data support current models of the neurocognition of morality according to which both emotional and cognitive components play an important role.

Resource allocation and fluid intelligence: Insights from pupillometry

Thinking is biological work and involves the allocation of cognitive resources. The aim of this study was to investigate the impact of fluid intelligence on the allocation of cognitive resources while one is processing low-level and high-level cognitive tasks. Individuals with high versus average fluid intelligence performed low-level choice reaction time tasks and high-level geometric analogy tasks. We combined behavioral measures to examine speed and accuracy of processing with pupillary measures that indicate resource allocation. Individuals with high fluid intelligence processed the low-level choice reaction time tasks faster than normal controls. The task-evoked pupillary responses did not differ between groups. Furthermore, individuals with high fluid intelligence processed the high-level geometric analogies faster, more accurately, and showed greater pupil dilations than normal controls. This was only true, however, for the most difficult analogy tasks. In addition, individuals with high fluid intelligence showed greater preexperimental pupil baseline diameters than normal controls. These results indicate that individuals with high fluid intelligence have more resources available and thus can solve more demanding tasks. Moreover, high fluid intelligence appears to be accompanied by more task-free exploration.

Emotional Stroop task: effect of word arousal and subject anxiety on emotional interference

Inconsistent findings regarding the emotional Stroop effect in healthy subjects may be explained by confounding effects of stimulus valence and arousal, as well as individual differences in anxiety. We examined reaction time data in a healthy sample using the emotional Stroop task while carefully matching arousal level of positive and negative words. Independent of valence, emotional relative to neutral words elicited emotional interference, indicating that arousal determines emotional interference. Independent of valence, emotional words were better re-called and recognized than neutral words. Individual differences in state anxiety were associated with emotional interference, that is, emotional interference was enhanced in subjects with high state anxiety. There was no influence of trait anxiety. These findings indicate that word arousal produces emotional interference independent of valence. State anxiety exacerbates interference of emotional words by further biasing attention towards emotionally salient stimuli.

A neural network reflecting individual differences in cognitive processing of emotions during perceptual decision making

Even simple perceptual decisions are influenced by the emotional content of a stimulus. Recent neuroimaging studies provide evidence about the neural mechanisms of perceptual decision making on emotional stimuli. However, the effect of individual differences in cognitive processing of emotions on perceptual decision making remains poorly understood. Here, we investigated how changes in the fMRI signal during perceptual decision making on facial stimuli covaried with individual differences in the ability to identify and communicate ones emotional state. Although this personality trait covaried with changes in activity in the dorsal anterior cingulate cortex (dACC) during gender decisions on facial expressions, there was no correlation during emotion decisions. Further, we investigated whether individual differences in the ability to cognitively process emotions depend on differences in the functional integration of emotional and cognitive brain regions. We therefore compared task-dependent changes in effective connectivity of dACC in individuals with good and with poor ability to cognitively process emotions using a psychophysiological interaction analysis. We found greater coupling of dACC with prefrontal regions in individuals with good ability to identify and communicate their emotional state. Conversely, individuals with poor ability in this domain showed greater coupling of dACC with the amygdala. Our data indicate that individual differences in the ability to identify and communicate ones emotional state are reflected by altered effective connectivity of the dACC with prefrontal and limbic regions. Thus, we provide neurophysiological evidence for a theoretical model that posits that a discommunication between limbic areas and the neocortex impairs cognitive processing of emotions.

Effective Connectivity of the Multiplication Network: A Functional MRI and Multivariate Granger Causality Mapping Study

Developmental neuropsychology and functional neuroimaging evidence indicates that simple and complex mental calculation is subserved by a fronto‐parietal network. However, the effective connectivity (connection direction and strength) among regions within the fronto‐parietal network is still unexplored. Combining event‐related fMRI and multivariate Granger Causality Mapping (GCM), we administered a multiplication verification task to healthy participants asking them to solve single and double‐digit multiplications. The goals of our study were first, to identify the effective connectivity of the multiplication network, and second, to compare the effective connectivity patterns between a low and a high arithmetical competence (AC) group. The manipulation of multiplication difficulty revealed a fronto‐parietal network encompassing bilateral intraparietal sulcus (IPS), left pre‐supplementary motor area (PreSMA), left precentral gyrus (PreCG), and right dorsolateral prefrontal cortex (DLPFC). The network was driven by an intraparietal IPS‐IPS circuit hosting a representation of numerical quantity intertwined with a fronto‐parietal DLPFC‐IPS circuit engaged in temporary storage and updating of arithmetic operations. Both circuits received additional inputs from the PreCG and PreSMA playing more of a supportive role in mental calculation. The high AC group compared to the low AC group displayed a greater activation in the right IPS and based its calculation more on a feedback driven intraparietal IPS‐IPS circuit, whereas the low competence group more on a feedback driven fronto‐parietal DLPFC‐IPS circuit. This study provides first evidence that multivariate GCM is a sensitive approach to investigate effective connectivity of mental processes involved in mental calculation and to compare group level performances for different populations. Hum Brain Mapp, 2010.

Cerebral correlates of analogical processing and their modulation by training

There is increasing interest in understanding the neural systems that mediate analogical thinking, which is essential for learning and fluid intelligence. The aim of the present study was to shed light on the cerebral correlates of geometric analogical processing and on training-induced changes at the behavioral and brain level. In healthy participants a bilateral fronto-parietal network was engaged in processing geometric analogies and showed greater blood oxygenation dependent (BOLD) signals as resource demands increased. This network, as well as fusiform and subcortical brain regions, additionally showed training-induced decreases in the BOLD signal over time. The general finding that brain regions were modulated by the amount of resources demanded by the task, and/or by the reduction of allocated resources due to short term training, reflects increased efficiency--in terms of more focal and more specialized brain activation--to more economically process the geometric analogies. Our data indicate a rapid adaptation of the cognitive system which is efficiently modulated by short term training based on a positive correlation of resource demands and brain activation.

Temporal order relations in language comprehension.

The role of temporal orientation (chronological or reverse) and chronological distance (close, intermediate, or distant) in general event knowledge on language comprehension was examined. Experiment 1 used a relation-recognition paradigm in which the comprehension of a target event could be facilitated or disrupted by the temporal orientation implied by the prior information. Experiments 2 and 3 used a sentence-probe-recognition paradigm in which the temporal orientation, the stimulus onset asynchrony, and the chronological distance between the sentence event and the probe event were manipulated. The results demonstrated that readers used temporal information conveyed by their knowledge to construct situation models while comprehending sentences. The internal temporal dimension appeared to be directional and reflected the chronological distance between everyday events.

Increased functional connectivity between prefrontal cortex and reward system in pathological gambling

Pathological gambling (PG) shares clinical characteristics with substance-use disorders and is thus discussed as a behavioral addiction. Recent neuroimaging studies on PG report functional changes in prefrontal structures and the mesolimbic reward system. While an imbalance between these structures has been related to addictive behavior, whether their dysfunction in PG is reflected in the interaction between them remains unclear. We addressed this question using functional connectivity resting-state fMRI in male subjects with PG and controls. Seed-based functional connectivity was computed using two regions-of-interest, based on the results of a previous voxel-based morphometry study, located in the prefrontal cortex and the mesolimbic reward system (right middle frontal gyrus and right ventral striatum). PG patients demonstrated increased connectivity from the right middle frontal gyrus to the right striatum as compared to controls, which was also positively correlated with nonplanning aspect of impulsiveness, smoking and craving scores in the PG group. Moreover, PG patients demonstrated decreased connectivity from the right middle frontal gyrus to other prefrontal areas as compared to controls. The right ventral striatum demonstrated increased connectivity to the right superior and middle frontal gyrus and left cerebellum in PG patients as compared to controls. The increased connectivity to the cerebellum was positively correlated with smoking in the PG group. Our results provide further evidence for alterations in functional connectivity in PG with increased connectivity between prefrontal regions and the reward system, similar to connectivity changes reported in substance use disorder.

Longitudinal Effects of Lesions on Functional Networks after Stroke

While ischemic stroke reflects focal damage determined by the affected vascular territory, clinical symptoms are often more complex and may be better explained by additional indirect effects of the focal lesion. Assumed to be structurally underpinned by anatomical connections, supporting evidence has been found using alterations in the functional connectivity of resting-state functional magnetic resonance imaging (fMRI) data in both sensorimotor and attention networks. To assess the generalizability of this phenomenon in a stroke population with heterogeneous lesions, we investigated the distal effects of lesions on a global level. Longitudinal resting-state fMRI scans were acquired at three consecutive time points, beginning during the acute phase (days 1, 7, and 90 post-stroke) in 12 patients after ischemic stroke. We found a preferential functional change in affected networks (i.e., networks containing lesions changed more during recovery when compared with unaffected networks). This change in connectivity was significantly correlated with clinical changes assessed with the National Institute of Health Stroke Scale. Our results provide evidence that the functional architecture of large-scale networks is critical to understanding the clinical effect and trajectory of post-stroke recovery.

Restoration in Urban Spaces Nature Views From Home, Greenways, and Public Parks

Despite promising experimental findings, few studies have addressed the potential long-term health benefits of frequent contact with different kinds of urban nature. We examine the cross-sectional relations between two kinds of urban nature (neighborhood vegetation visible from the home, use of public green spaces) and health outcomes (life satisfaction, perceived general health, 2-months hair cortisol levels) in a sample population from Berlin (N = 32) using a mixed-method approach. Participants whose homes had views of high amounts of diverse kinds of vegetation had significantly lower cortisol levels. Moreover, participants who regularly used a vegetated trail along a canal had significantly lower cortisol levels and reported significantly higher life satisfaction than less frequent users. In addition, vegetated routes or paths played an important role in the restorative activities and daily commutes of participants. We discuss directions for future research and recommend more consideration of greenways in urban development.