Papers by Bernhard Hommel
Cognitive Systems, 2008
We describe an embodied cognitive system based on a three-level architecture that includes a sens... more We describe an embodied cognitive system based on a three-level architecture that includes a sensorimotor layer, a mid-level layer that stores and reasons about object-action episodes, and a high-level symbolic planner that creates abstract action plans to be realised and possibly further specified by the lower levels. The system works in two modes, exploration and plan execution, that both make
Assessing interactions between cognition, emotion, and motivation in creativity: The construction and validation of EDICOS
Thinking Skills and Creativity
There is increasing evidence suggesting that individual differences in creativity reflect particu... more There is increasing evidence suggesting that individual differences in creativity reflect particular combinations of thinking styles, affective dispositions, and motivational preferences. Unfortunately, available performance tests and self-report inventories assess these factors in isolation, which calls for a more systematic measurement of the interactions between cognition, emotion, and motivation. The aim of the present study was to develop a questionnaire that allows for the assessment of individual differences in divergent and convergent creativity, as well as the identification of particular cognitive/affective/motivational associations.
Individuals with Autism Spectrum Disorders (ASD) have been assumed to show evidence of abnormal v... more Individuals with Autism Spectrum Disorders (ASD) have been assumed to show evidence of abnormal visuospatial processing, which has been attributed to a failure to integrate local features into coherent global Gestalts and/or to a bias towards local processing. As the available data are based on baseline performance only, which does not provide insight into cognitive/neural plasticity and actual cognitive potential, we investigated how training-resistant possible visuospatial processing differences between children with and without ASD are. In particular, we studied the effect of computerized vs. face-to-face visuospatial training in a group of not-high-functioning children with ASD and typically developing children as control. Findings show that (a) children with and without ASD do not differ much in visuospatial processing (as assessed by a tangram-like task) and the few differences we observed were all eliminated by training; (b) training can improve visuospatial processing (equally) in both ASD and normally developing children; and (c) computer-based and face-to-face training was equally effective.
The impact of binaural beats on creativity
Human creativity relies on a multitude of cognitive processes, some of which are influenced by th... more Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through stimulating neuronal phase locking. We aimed to investigate whether binaural beats affect creative performance at all, whether they affect divergent thinking, convergent thinking, or both, and whether possible effects may be mediated by the individual striatal dopamine level. Binaural beats were presented at alpha and gamma frequency. Participants completed a divergent and a convergent thinking task to assess two important functions of creativity, and filled out the Positive And Negative Affect Scale-mood State questionnaire (PANAS-S) and an affect grid to measure current mood. Dopamine levels in the striatum were estimated using spontaneous eye blink rates (EBRs). Results showed that binaural beats, regardless of the presented frequency, can affect divergent but not convergent thinking. Individuals with low EBRs mostly benefitted from alpha binaural beat stimulation, while individuals with high EBRs were unaffected or even impaired by both alpha and gamma binaural beats. This suggests that binaural beats, and possibly other forms of cognitive entrainment, are not suited for a one-size-fits-all approach, and that individual cognitive-control systems need to be taken into account when studying cognitive enhancement methods.
Passionate love is associated with intense changes in emotion and attention which are thought to ... more Passionate love is associated with intense changes in emotion and attention which are thought to play an important role in the early stages of romantic relationship formation. Although passionate love usually involves enhanced, near-obsessive attention to the beloved, anecdotal evidence suggest that the lover's concentration for daily tasks like study and work may actually be impaired, suggesting reduced cognitive control. Affect might also contribute to changes in cognitive control. We examined the link between passionate love and cognitive control in a sample of students who had recently become involved in a romantic relationship. Intensity of passionate love as measured by the Passionate Love Scale was shown to correlate with decreased individual efficiency in cognitive control as measured in Stroop and flanker task performance. There was no evidence that affective changes mediate this effect. This study provides the first empirical evidence that passionate love in the early stages of romantic relationship is characterized by impaired cognitive control.
Two experiments studied the temporal dynamics of feature integration with auditory (Experiment 1)... more Two experiments 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 if the second of two consecutive stimuli shared all or none of the features of the first rather than if only one of the features overlapped; and comparable partial-overlap costs were obtained for combinations of stimulus features and the responses.
Cognitive control and the COMT Val158Met polymorphism: genetic modulation of videogame training and transfer to task-switching efficiency
The study investigated whether successful transfer of game-based cognitive improvements to untrai... more The study investigated whether successful transfer of game-based cognitive improvements to untrained tasks might be modulated by preexisting neuro-developmental factors, such as genetic variability related to the catechol-O-methyltransferase (COMT)-an enzyme responsible for the degradation of dopamine. The COMT Val(158)Met genotype may differentially affect cognitive stability and flexibility, and we hypothesized that Val/Val homozygous individuals (who possess low prefrontal dopamine levels) show more pronounced cognitive flexibility than Met/-carriers (who possess high prefrontal dopamine levels). We trained participants, genotyped for the COMT Val(158)Met polymorphism on playing "Half-Life 2", a first-person shooter game which has been shown to improve cognitive flexibility. Pre-training (baseline) and post-training measures of cognitive flexibility were acquired by means of a task-switching paradigm. As expected, Val/Val homozygous individuals showed larger beneficial transfer effects than Met/-carriers. Our findings support the idea that genetic predisposition modulates transfer effects and that playing first-person shooter games promotes cognitive flexibility in individuals with a suitable genetic predisposition.
This article reviews evidence suggesting that the cause of approach and avoidance behavior lies n... more This article reviews evidence suggesting that the cause of approach and avoidance behavior lies not so much in the presence (i.e., the stimulus) but, rather, in the behavior's anticipated future consequences (i.e., the goal): Approach is motivated by the goal to produce a desired consequence or end-state, while avoidance is motivated by the goal to prevent an undesired consequence or endstate. However, even though approach and avoidance are controlled by goals rather than stimuli, affective stimuli can influence action control by priming associated goals. An integrative ideomotor model of approach and avoidance is presented and discussed.
Front. Hum. Neurosci., 2013
Khat consumption has become a worldwide phenomenon broadening from Eastern Africa and the south w... more Khat consumption has become a worldwide phenomenon broadening from Eastern Africa and the south west of the Arabian Peninsula to ethnic communities in the rest of the world. So far, the cognitive effects of khat use are poorly understood and no studies have looked into the relation between acute khat use and cognitive control functions, the way we control our thoughts and goal directed behavior. We studied how acute khat use affects the emergence and the resolution of response conflict, a central cognitive control function. Khat users (n = 11) and khat-free controls (n = 18) were matched in terms of education, sex, alcohol, and cannabis consumption. Groups were tested on response conflict, as measured by the Simon task. In one single session, participants worked through two task blocks: the khat group chewed exclusively khat whereas the khat-free group chewed solely a gum. Results showed that in the second block, which reflects the acute impact of khat, the khat group was better than controls in resolving stimulus-induced response conflict as indexed by a smaller Simon effect. These results suggest that the acute intake of khat may improve participants' ability of handling response conflict.
Neuropsychologia, 2014
One of the most important functions of cognitive control is to continuously adapt cognitive proce... more One of the most important functions of cognitive control is to continuously adapt cognitive processes to changingand often conflicting demands of the environment.Dopamine (DA) has been suggested to play a key role in the signaling and resolution of such response conflict.Given that DA is found in high concentration in the retina, color vision discrimination has been suggested as an index of DA functioning and in particular blue-yellow color vision impairment (CVI) has been used to indicate a central hypodopaminergic state. We used color discrimination (indexed by the total color distance score; TCDS) to predict individual differences in the cognitive control of response conflict, as reflected by conflict-resolution efficiency in an auditory Simon task. As expected, participants showing better color discrimination were more efficient in resolving response conflict.Interestingly, participants showing a blue-yellow CVIwere associated withless efficiency in handling response conflict.
Frontiers in Psychology, 2014
Interpersonal trust is an essential ingredient of many social relationships but how stable is it ... more Interpersonal trust is an essential ingredient of many social relationships but how stable is it actually, and how is it controlled? There is evidence that the degree of trust into others might be rather volatile and can be affected by manipulations like drawing attention to personal interdependence or independence. Here we investigated whether the degree of interpersonal trust can be biased by inducing either a more integrative or a more focused/exclusive cognitive control mode by means of a creativity task requiring divergent or convergent thinking, respectively. Participants then performed the trust game, which provides an index of interpersonal trust by assessing the money units one participant (the trustor) transfers to another (the trustee). As expected, trustors transferred significantly more money to trustees after engaging in divergent thinking as compared to convergent thinking. This observation provides support for the idea that interpersonal trust is controlled by domain-general (i.e., not socially dedicated) cognitive states.
Psychonomic Bulletin & Review, 2007
The Experience of Crowding in Real-Life Environments: An Action Oriented Approach
Environmental Social Psychology, 1988
Psychonomic Bulletin & Review, 2006
People integrate the features of perceived events and of action plans, as well as of episodic sti... more People integrate the features of perceived events and of action plans, as well as of episodic stimulusresponse relations, into event files. We investigated whether the management of event files, and particularly the speed of updating the binding between the task-relevant stimulus feature and the response, correlates with fluid intelligence. Indeed, the performance of participants scoring high on Raven's Standard Progressive Matrices test was less impaired by a mismatch between the stimulus-response relation in the current and the previous trial. This result suggests that high intelligence is accompanied by a higher degree of flexibility in handling event files-that is, by higher efficiency in updating episodic representations.
Referential Response Coding in the Go-Nogo Simon Task
PsycEXTRA Dataset, 2000
Attentional scanning in the selection of central targets from multi-symbol strings
Visual Cognition, 1995
... In sum, then, spotlight approaches have no convincing explanation of the asymmetrically distr... more ... In sum, then, spotlight approaches have no convincing explanation of the asymmetrically distributed FCE, and ... through the string for a target letter (Krueger, 1976).* Even memory load does not ... To account for these find-ings, several variants of an attentional theory first proposed ...
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Papers by Bernhard Hommel