Cognitive flexibility and religious disbelief.

Cognitive flexibility is operationalized in the neuropsychological literature as the ability to shift between modes of thinking and adapt to novel or changing environments. Religious belief systems consist of strict rules and rituals that offer adherents certainty, consistency, and stability. Consequently, we hypothesized that religious adherence and practice of repetitive religious rituals may be related to the persistence versus flexibility of one's cognition. The present study investigated the extent to which tendencies towards cognitive flexibility versus persistence are related to three facets of religious life: religious affiliation, religious practice, and religious upbringing. In a large sample (N = 744), we found that religious disbelief was related to cognitive flexibility across three independent behavioural measures: the Wisconsin Card Sorting Test, Remote Associates Test, and Alternative Uses Test. Furthermore, lower frequency of religious service attendance was related to cognitive flexibility. When analysing participants' religious upbringing in relation to their current religious affiliation, it was manifest that current affiliation was more influential than religious upbringing in all the measured facets of cognitive flexibility. The findings indicate that religious affiliation and engagement may shape and be shaped by cognitive control styles towards flexibility versus persistence, highlighting the tight links between flexibility of thought and religious ideologies.

Zooming into creativity: individual differences in attentional global-local biases are linked to creative thinking.

While recent studies have investigated how processes underlying human creativity are affected by particular visual-attentional states, we tested the impact of more stable attention-related preferences. These were assessed by means of Navon's global-local task, in which participants respond to the global or local features of large letters constructed from smaller letters. Three standard measures were derived from this task: the sizes of the global precedence effect, the global interference effect (i.e., the impact of incongruent letters at the global level on local processing), and the local interference effect (i.e., the impact of incongruent letters at the local level on global processing). These measures were correlated with performance in a convergent-thinking creativity task (the Remote Associates Task), a divergent-thinking creativity task (the Alternate Uses Task), and a measure of fluid intelligence (Raven's matrices). Flexibility in divergent thinking was predicted by the local interference effect while convergent thinking was predicted by intelligence only. We conclude that a stronger attentional bias to visual information about the "bigger picture" promotes cognitive flexibility in searching for multiple solutions.

Zapping the gap: Reducing the multisensory temporal binding window by means of transcranial direct current stimulation (tDCS).

Synchrony among the senses lies at the heart of our possession of a unified conscious perception of the world. However, due to discrepancies in physical and neural information processing from different senses, the brain accommodates a limited range of temporal asynchronies between sensory inputs, i.e. the multisensory temporal binding window (TBW). Using non-invasive brain stimulation, we sought to modulate the audio-visual TBW and to identify cortical areas implicated in the conscious perception of multisensory synchrony. Participants performed a simultaneity judgment task while experiencing anodal (Experiment 1) or cathodal (Experiment 2) transcranial direct current stimulation (tDCS) over parietal and frontal regions. The results demonstrate that stimulating the right posterior parietal cortex significantly reduces the audio-visual TBW by approximately 30%, thereby causally linking this region to the plasticity of the TBW. This highlights a potential interventional technique for populations with a wider TBW, such as in autism and dyslexia.

The role of the parietal cortex in multisensory and response integration: evidence from transcranial direct current stimulation (tDCS).

The question of how the brain forms unified representations from multisensory data that are processed in distinct cortical regions is known in the literature as 'the binding problem'. In the last decade, several studies have suggested possible neural mechanisms and brain regions that might be involved in integration processes. One of the brain regions that is implicated with multisensory perception is the posterior parietal cortex (PPC). Evidence from patients with parietal lesions suggests the involvement of the PPC in coherent perception. Here, we investigated the role of the PPC in multisensory feature integration through experimental manipulation of non-invasive brain stimulation with healthy participants using transcranial direct current stimulation (tDCS). In different sessions, healthy participants received anodal, cathodal, or sham stimulation (2 mA, 20 min) over the right PPC while performing an audio-visual event-file task. The results underscore two interesting observations. Firstly, there was a significant difference in integration effects between features from different modalities in the anodal stimulation compared to sham, suggesting interference of the multisensory integration processes during the brain stimulation. And secondly, after anodal stimulation, the unattended feature became more likely to be integrated with the response feature compared to the other conditions, presumably through an interference of attentional processes. Hence, these findings emphasize the role of the right PPC in multisensory integration. Furthermore, from a methodological perspective, tDCS can be used as an experimental tool by creating a temporary, reversible disruption in cognitive processes in order to explore the mechanisms underlying cognitive functions.

Evidence for a role of the right dorsolateral prefrontal cortex in controlling stimulus-response integration: a transcranial direct current stimulation (tDCS) study.

BACKGROUND: Acting coherently upon stimuli requires some kind of integration of stimulus and response features across various distinct cortical feature maps (one aspect of the binding problem). Although the process of feature binding proper seems rather automatic, recent studies revealed that the management of stimulus-response bindings is less efficient in populations with impaired cognitive-control processes. OBJECTIVE: Here, we investigated whether the cognitive control of stimulus-response feature bindings ("event files") in healthy participants is affected by non-invasive brain stimulation (tDCS) of the dorsolateral prefrontal cortex (DLPFC)-a main component of the cognitive-control network. METHOD: In different sessions, participants received anodal, cathodal, or sham tDCS (2 mA, 20 min) while performing an audio-visual event-file task assessing the creation and retrieval of stimulus-stimulus and stimulus-response feature bindings. The general findings from this task indicate that performance suffers when some, but not all of the features are repeated (the so-called partial repetition cost). RESULTS: Stimulation over the right, but not the left DLPFC reduced control of stimulus-response bindings and produced outcome patterns similar to those previously observed in autistic children, people with lower fluid intelligence, and older adults. CONCLUSIONS: This finding provides empirical support for a role of the right DLPFC in feature-binding management, which might consist in preventing the stimulus-induced activation of previously created, but now task-irrelevant, episodic bindings. From a methodological perspective, the finding may suggest that tDCS could be used as a temporary, reversible "brain lesion" generator in healthy subjects, enabling experimental investigation of how the brain works.

Attentional control of the creation and retrieval of stimulus-response bindings.

Two experiments studied the degree to which the creation and retrieval of episodic feature bindings is modulated by attentional control. Experiment 1 showed that the impact of bindings between stimulus and response features varies as a function of the current attentional set: only bindings involving stimulus features that match the current set affect behavior. Experiment 2 varied the time point at which new attentional sets were implemented-either before or after the processing of the to-be-integrated stimuli and responses. The time point did not matter, suggesting that the attentional set has no impact on feature integration proper but controls which features get access to and can thus trigger the retrieval of bindings.

Dopamine, norepinephrine, and the management of sensorimotor bindings: individual differences in updating of stimulus-response episodes are predicted by DAT1, but not DBH5'-ins/del.

Evidence suggests that the flexibility of managing (creating and updating) stimulus-response bindings is driven by the dopaminergic system. Given that striatal dopamine (DA) plays a crucial role in the updating of working memory, the present study tested whether individual differences in the efficiency of updating stimulus-response episodes (event files) are predicted by differences in genetic predisposition related to the efficiency of the striatal dopaminergic pathway. In view of contrasting claims that stimulus-response binding is related to norepinephrine, we also considered genetic predispositions regarding noradrenergic pathways. In a sample of 100 healthy adults, we studied whether the degree to which stimulus-response bindings affect ongoing performance is predicted by polymorphisms of the dopamine transporter gene (DAT1, associated with striatal DA levels) and DBH5'-ins/del (strongly correlated with dopamine beta-hydroxylase, the enzyme catalyzing the dopamine-norepinephrine conversion). The performance of 9-repeat carriers of the DAT1 gene was more affected by stimulus-response bindings than the performance of 10/10 homozygotes was, while DBH5'-ins/del polymorphism was not related to performance. This outcome pattern suggests a crucial role of the nigrostriatal dopaminergic pathway in the flexible management of stimulus-response episodes, whereas norepinephrine does not seem to play a role.

Feature integration across multimodal perception and action: a review.

The human brain is facing a continuous stream of stimulus information delivered by multiple modalities and sensory channels and processed in distinct cortical regions. We discuss recent empirical and theoretical developments in addressing the question of how this distributed information is integrated into coherent representations (the so-called binding problem) with an emphasis on the principles and constraints underlying the integration of multiple (rather than redundant) features across different sensory modalities and across perception and action planning.

Action video gaming and cognitive control: playing first person shooter games is associated with improvement in working memory but not action inhibition.

The interest in the influence of videogame experience in our daily life is constantly growing. "First Person Shooter" (FPS) games require players to develop a flexible mindset to rapidly react and monitor fast moving visual and auditory stimuli, and to inhibit erroneous actions. This study investigated whether and to which degree experience with such videogames generalizes to other cognitive control tasks. Experienced video game players (VGPs) and individuals with little to no videogame experience (NVGPs) performed on a N-back task and a stop-signal paradigm that provide a relatively well-established diagnostic measure of the monitoring and updating of working memory (WM) and response inhibition (an index of behavioral impulsivity), respectively. VGPs were faster and more accurate in the monitoring and updating of WM than NVGPs, which were faster in reacting to go signals, but showed comparable stopping performance. Our findings support the idea that playing FPS games is associated with enhanced flexible updating of task-relevant information without affecting impulsivity.

Cognitive control of feature bindings: evidence from children with autistic spectrum disorder.

Understanding how the brain integrates features from different domains that are processed in distinct cortical regions calls for the examination of integration processes. Recent studies of feature-repetition effects demonstrated interactions across perceptual features and action-related features: repeating only some features of the perception-action episode hinders performance. These partial-repetition costs point to the existence of temporary memory traces (event files). However, the principles and the constraints that govern the management of such traces are still unclear. Here, we investigated whether children with autistic spectrum disorder (ASD) differ from typically developing children in managing episodic memory traces. The results show that both groups integrate stimulus features along with action features, but children with ASD exhibit larger partial-repetition costs, suggesting lesser control and flexibility in updating episodic memory traces. The findings are discussed in the light of evidence for a central role of the dopaminergic system in cognitive integration, ASD, and cognitive control.

Dopaminergic modulation of the updating of stimulus-response episodes in Parkinson's disease.

Increasing evidence suggests that the control of retrieval of episodic feature bindings is modulated by the striatal dopaminergic pathway. The present study investigated whether this may reflect a contribution from the ventral or the dorsal part of the striatum. Along the lines of the overdose hypothesis in Parkinson's disease (PD), functions known to rely on the dorsal striatum are enhanced with dopaminergic medication, while operations relying on the ventral circuitry are impaired. We found that partial mismatches between present and previous stimulus-response relations are, compared to control participants, abnormally low OFF DA medication and normalized ON DA medication. The results suggest that the dorsal striatum, but not (or not so much) the ventral striatum, is driving the flexible control of retrieval of stimulus-response episodes.

The relationship between feature binding and consciousness: evidence from asynchronous multi-modal stimuli.

Processing the various features from different feature maps and modalities in coherent ways requires a dedicated integration mechanism ("the binding problem"). Many authors have related feature binding to conscious awareness but little is known about how tight this relationship really is. We presented subjects with asynchronous audiovisual stimuli and tested whether the two features were integrated. The results show that binding took place up to 350 ms feature-onset asynchronies, suggesting that integration covers a relatively wide temporal window. We also asked subjects to explicitly judge whether the two features would belong to the same or to the different events. Unsurprisingly, synchrony judgments decreased with increasing asynchrony. Most importantly, feature binding was entirely unaffected by conscious experience: features were bound whether they were experienced as occurring together or as belonging to a separate events, suggesting that the conscious experience of unity is not a prerequisite for, or a direct consequence of binding.

Temporal dynamics of unimodal and multimodal feature binding.

In two experiments, we studied the temporal dynamics of feature integration with auditory (Experiment 1) and audiovisual (Experiment 2) stimuli and manual responses. Consistent with previous observations, performance was better when the second of two consecutive stimuli shared all or none of the features of the first, rather than when only one of the features overlapped. Comparable partial-overlap costs were obtained for combinations of stimulus features and responses. These effects decreased systematically with increasing time between the two stimulus-and-response events, and the decreased rate was comparable for unimodal and multimodal bindings. General effect size reflected the degree of task relevance of the dimension or modality of the respective feature, but the effects of relevance and of temporal delay did not interact. This suggests that the processing of stimuli on task-relevant sensory modalities and feature dimensions is facilitated by task-specific attentional sets, whereas the temporal dynamics might reflect that bindings "decay" or become more difficult to access over time.

Auditory event files: integrating auditory perception and action planning.

The features of perceived objects are processed in distinct neural pathways, which call for mechanisms that integrate the distributed information into coherent representations (the binding problem). Recent studies of sequential effects have demonstrated feature binding not only in perception, but also across (visual) perception and action planning. We investigated whether comparable effects can be obtained in and across auditory perception and action. The results from two experiments revealed effects indicative of spontaneous integration of auditory features (pitch and loudness, pitch and location), as well as evidence for audio-manual stimulus-response integration. Even though integration takes place spontaneously, features related to task-relevant stimulus or response dimensions are more likely to be integrated. Moreover, integration seems to follow a temporal overlap principle, with features coded close in time being more likely to be bound together. Taken altogether, the findings are consistent with the idea of episodic event files integrating perception and action plans.

Intermodal event files: integrating features across vision, audition, taction, and action.

Understanding how the human brain integrates features of perceived events calls for the examination of binding processes within and across different modalities and domains. Recent studies of feature-repetition effects have demonstrated interactions between shape, color, and location in the visual modality and between pitch, loudness, and location in the auditory modality: repeating one feature is beneficial if other features are also repeated, but detrimental if not. These partial-repetition costs suggest that co-occurring features are spontaneously bound into temporary event files. Here, we investigated whether these observations can be extended to features from different sensory modalities, combining visual and auditory features in Experiment 1 and auditory and tactile features in Experiment 2. The same types of interactions, as for unimodal feature combinations, were obtained including interactions between stimulus and response features. However, the size of the interactions varied with the particular combination of features, suggesting that the salience of features and the temporal overlap between feature-code activations plays a mediating role.