Publications by authors named "Hommel B"

Ideomotor theories claim that carrying out a movement that produces a perceivable effect creates a bidirectional association between the two, which can then be used by action control processes to retrieve the associated action by anticipating its outcome. Previous implicit-learning studies have shown that practice renders novel but action-contingent stimuli effective retrieval cues of the action they used to follow, suggesting that experiencing sequences of actions and effects creates bidirectional action-effect associations. We investigated whether action-effect associations are also acquired under explicit learning conditions and whether familiar action-effect relations (such as between a trumpet and a trumpet sound) are learned the same way as novel, arbitrary relations are.

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Performing two tasks concurrently is difficult, which has been taken to imply the existence of a structural processing bottleneck. Here we sought to assess whether and to what degree one's multitasking abilities depend on the cognitive-control style one engages in. Participants were primed with creativity tasks that either called for divergent thinking-which were suspected to induce a holistic, flexible task processing mode, or convergent thinking-which were assumed to induce a systematic, focused processing mode.

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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.

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Negative affect in healthy populations regulates the appraisal of demanding situations, which tunes subsequent effort mobilization and adjustments in cognitive control. In the present study, we hypothesized that dysphoria in depressed individuals similarly modulates this adaptation, possibly through a neural mechanism involving serotonergic regulation. We tested the effect of dysphoria induced by acute tryptophan depletion (ATD) in remitted depressed patients on conflict adaptation in a Simon task.

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Stressful situations, the aversiveness of events, or increases in task difficulty (e.g., conflict) have repeatedly been shown to be capable of triggering attentional control adjustments.

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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.

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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).

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Chronic cannabis use has been shown to block long-term depression of GABA-glutamate synapses in the striatum, which is likely to reduce the extent to which endogenous cannabinoids modulate GABA- and glutamate-related neuronal activity. The current study aimed at investigating the effect of this process on striatal dopamine levels by studying the spontaneous eye blink rate (EBR), a clinical marker of dopamine level in the striatum. 25 adult regular cannabis users and 25 non-user controls matched for age, gender, race, and IQ were compared.

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Estrogen has a key role in explaining gender differences in dopaminergic functioning. To date, previous studies on estrogen have focused on inhibitory output control, such as the intentional suppression of overt pre-potent actions, but whether input control is also modulated is an open question. For the first time, this study compared the ability to perform a cued target-detection task that measured inhibition of return (IOR), a reflexive inhibitory mechanism that delays attention from returning to a previously attended location, in young women (n=21) across the three phases of their menstrual cycle (salivary estradiol and progesterone concentrations were assessed) and in young men (n=21).

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Bilingualism is commonly assumed to improve creativity but the mechanisms underlying creative acts, and the way these mechanisms are affected by bilingualism, are not very well understood. We hypothesize that learning to master multiple languages drives individuals toward a relatively focused cognitive-control state that exerts strong top-down impact on information processing and creates strong local competition for selection between cognitive codes. Considering the control requirements posed by creativity tasks tapping into convergent and divergent thinking, this predicts that high-proficient bilinguals should outperform low-proficient bilinguals in convergent thinking, while low-proficient bilinguals might be better in divergent thinking.

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It has been shown that negative affect causes attentional narrowing. According to Easterbrook's (1959) influential hypothesis this effect is driven by the withdrawal motivation inherent to negative emotions and might be related to increases in arousal. We investigated whether valence-unspecific increases in physiological arousal, as measured by pupil dilation, could account for attentional narrowing effects in a cognitive control task.

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Humans integrate the features of perceived events and of action plans into episodic event files. Here we investigated whether children (9-10 years), younger adults (20-31 years), and older adults (64-76 years) differ in the flexibility of managing (updating) event files. Relative to young adults, performance in children and older adults was more hampered by partial mismatches between present and previous stimulus-response relations, suggesting less efficient updating of episodic stimulus-response representations in childhood and old age.

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Western society has an increasing proportion of older adults. Increasing age is associated with a general decrease in the control over task-relevant mental processes. In the present study we investigated the possibility that successful transfer of game-based cognitive improvements to untrained tasks in elderly people is modulated by preexisting neuro-developmental factors as genetic variability related to levels of the brain-derived neurotrophic factor (BDNF), an important neuromodulator underlying cognitive processes.

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Introduction: Many migraine patients report cognitive complaints during the first hours or days following a migraine attack. The aim of this study was to assess whether and which cognitive (perceptual, attentional, or memory) processes are impaired during the first 48 hours after a migraine attack.

Methods: Three different cognitive tasks (global-local task, the attentional network task, and N-back task) were administered to 16 migraine patients (13 migraine without aura; mean age 58 years, 15 female) and 18 controls (59 years, 15 female), matched on age, gender, and educational level.

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Behavioral and psychophysiological studies on the Simon effect have demonstrated that stimuli automatically activate spatially corresponding responses, even if their location is irrelevant to the task. Interestingly, this Simon effect is attenuated after stimulus-response incompatible trials (Gratton effect or compatibility-sequence effect), a pattern that has often been attributed to online conflict adaptation, even though an account in terms of episodic binding and retrieval is just as plausible. Here we show that the compatibility-sequence effect can be eliminated and partly reversed by rotating the boxes in which stimuli are presented in between two given trials, a manipulation that is likely to affect episodic representation but not online control.

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Dual tasks and their associated delays have often been used to examine the boundaries of processing in the brain. We used the dual-task procedure and recorded event-related potentials (ERPs) to investigate how mental rotation of a first stimulus (S1) influences the shifting of visual-spatial attention to a second stimulus (S2). Visual-spatial attention was monitored by using the N2pc component of the ERP.

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Rationale: Khat consumption has increased during the last decades in Eastern Africa and has become a global phenomenon spreading to ethnic communities in the rest of the world, such as The Netherlands, United Kingdom, Canada, and the United States. Very little is known, however, about the relation between khat use and cognitive control functions in khat users.

Objective: We studied whether khat use is associated with changes in working memory (WM) and cognitive flexibility, two central cognitive control functions.

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Increasing evidence suggests that emotions affect cognitive processes. Recent approaches have also considered the opposite: that cognitive processes might affect people's mood. Here we show that performing and, to a lesser degree, preparing for a creative thinking task induce systematic mood swings: Divergent thinking led to a more positive mood, whereas convergent thinking had the opposite effect.

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In the standard Simon task, participants carry out spatially defined responses to non-spatial stimulus attributes. Responses are typically faster when stimulus location and response location correspond. This effect disappears when a participant responds to only one of the two stimuli and reappears when another person carries out the other response.

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Robots are increasingly expected to perform tasks in complex environments. To this end, engineers provide them with processing architectures that are based on models of human information processing. In contrast to traditional models, where information processing is typically set up in stages (i.

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Background: The brain-derived neurotrophic factor (BDNF) is a key protein in maintaining neuronal integrity. The BDNF gene is thought to play an important role in the pathophysiology of mood and anxiety disorders. The aim of this study was to investigate, for the first time in a single study, the association between BDNF Val(66)Met polymorphism, anxiety, alcohol consumption, and cortisol stress response.

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The attentional blink (AB)--a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distracters--has been related to processing limitations in working memory. Given that dopamine (DA) plays a crucial role working memory, the present study tested whether individual differences in the size of the AB can be predicted by differences in genetic predisposition related to the efficiency of dopaminergic pathways. Polymorphisms related to mesocortical and nigrostriatal dopaminergic pathways were considered, as well as polymorphisms related to norepinephrine (NE), a transmitter system that has also been suspected to play a role in the AB.

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Previous findings suggest that religion has a specific impact on attentional processes. Here we show that religion also affects action control. Experiment 1 compared Dutch Calvinists and Dutch atheists, matched for age, sex, intelligence, education, and cultural and socio-economic background, and Experiment 2 compared Italian Catholics with matched Italian seculars.

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Conceptual knowledge is acquired through recurrent experiences, by extracting statistical regularities at different levels of granularity. At a fine level, patterns of feature co-occurrence are categorized into objects. At a coarser level, patterns of concept co-occurrence are categorized into contexts.

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As was shown by Wykowska, Schubö, and Hommel (Journal of Experimental Psychology, Human Perception and Performance, 35, 1755-1769, 2009), action control can affect rather early perceptual processes in visual search: Although size pop-outs are detected faster when having prepared for a manual grasping action, luminance pop-outs benefit from preparing for a pointing action. In the present study, we demonstrate that this effect of action-target congruency does not rely on, or vary with, set-level similarity or element-level similarity between perception and action-two factors that play crucial roles in standard stimulus-response interactions and in models accounting for these interactions. This result suggests that action control biases perceptual processes in specific ways that go beyond standard stimulus-response compatibility effects and supports the idea that action-target congruency taps into a fundamental characteristic of human action control.

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