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1.
J Cogn Neurosci ; 36(3): 522-533, 2024 03 01.
Article in English | MEDLINE | ID: mdl-38165734

ABSTRACT

Classical conditioning states that the systematic co-occurrence of a neutral stimulus with an unconditioned stimulus can cause the neutral stimulus to, over time, evoke the same response as the unconditioned stimulus. On a neural level, Hebbian learning suggests that this type of learning occurs through changes in synaptic plasticity when two neurons are simultaneously active, resulting in increased connectivity between them. Inspired by associative learning theories, we here investigated whether the mere co-activation of visual stimuli and stimulation of the primary motor cortex using TMS would result in stimulus-response associations that can impact future behavior. During a learning phase, we repeatedly paired the presentation of a specific color (but not other colors) with a TMS pulse over the motor cortex. Next, participants performed a two-alternative forced-choice task where they had to categorize simple shapes and we studied whether the shapes' task-irrelevant color (and its potentially associated involuntary motor activity) affected the required motor response. Participants showed more errors on incongruent trials for stimuli that were previously paired with high intensity TMS pulses, but only when tested on the same day. Using a drift diffusion model for conflict tasks, we further demonstrate that this interference occurred early, and gradually increased as a function of associated TMS intensity. Taken together, our findings show that the human brain can learn stimulus-response associations using externally induced motor cortex stimulation. Although we were inspired by the Hebbian learning literature, future studies should investigate whether Hebbian or other learning processes were also what brought about this effect.


Subject(s)
Conditioning, Classical , Transcranial Magnetic Stimulation , Humans , Conditioning, Classical/physiology , Transcranial Magnetic Stimulation/methods , Evoked Potentials, Motor/physiology , Learning/physiology , Neuronal Plasticity/physiology
3.
Conscious Cogn ; 107: 103448, 2023 01.
Article in English | MEDLINE | ID: mdl-36481575

ABSTRACT

A growing number of studies demonstrate that belief in free will (FWB) is dynamic, and can be reduced experimentally. Most of these studies assume that doing so has beneficial effects on behavior, as FWBs are thought to subdue unwanted automatic processes (e.g. racial stereotypes). However, relying on automatic processes can sometimes be advantageous, for instance during implicit learning (e.g. detecting and exploiting statistical regularities in the environment). In this registered report, we tested whether experimentally reducing FWBs positively affected implicit motor learning. We hypothesized that reducing FWBs would lead to both faster and stronger implicit learning, as measured using the alternating serial reaction time (ASRT) task. While we did show a manipulation effect on free will beliefs, there was no detectable effect on implicit learning processes. This finding adds to the growing body of evidence that free will belief manipulations do not meaningfully affect downstream behavior.


Subject(s)
Learning , Personal Autonomy , Humans , Reaction Time , Serial Learning
4.
J Neuropsychol ; 17(2): 264-278, 2023 06.
Article in English | MEDLINE | ID: mdl-36303524

ABSTRACT

Prior work on patients with Parkinson's disease (PD) has shown that the administration of dopaminergic medication in the early to intermediate stages of PD benefits (motor) functions associated with the dopamine-depleted dorsal striatal circuitry but may 'overdose' and interfere with (cognitive) functions associated with the relatively intact ventral striatal circuitry. The present study aimed to elucidate this so-called dopamine overdose hypothesis for the action control domain. Using a within-subject design in a sample of 13 people with PD, we evaluated the effect of dopaminergic medication on two cognitive processes underlying goal-directed behaviour, namely action selection and initiation through event binding and conflict adaptation. We also investigated whether individual differences in the magnitude of medication effects were associated across these processes. Results showed no indications that dopaminergic medication affects action selection and initiation or conflict adaptation in PD patients. Additionally, we observed no correlations between both cognitive processes nor between individual differences in medication effects. Our findings do not support the notion that dopaminergic medication modulates action control processes, suggesting that the dopamine overdose hypothesis may only apply to a specific set of cognitive processes and should potentially be refined.


Subject(s)
Parkinson Disease , Humans , Parkinson Disease/drug therapy , Parkinson Disease/complications , Dopamine/metabolism , Dopamine/therapeutic use , Neuropsychological Tests , Dopamine Agents/pharmacology , Dopamine Agents/therapeutic use , Cognition
5.
J Exp Psychol Gen ; 151(11): 2812-2832, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35511566

ABSTRACT

Humans excel in instruction following to boost performance in unfamiliar situations. We can do so through so-called prepared reflexes: Abstract instructions are instantly translated into appropriate task rules in procedural working memory, after which imperative stimuli directly trigger their corresponding responses in a ballistic, reflex-like manner. But how much control do we have over these instructed task rules when their reflexes suddenly lose their relevance? Inspired by the phenomenon of directed forgetting in declarative working memory, we here tested across four experiments whether the presentation of (implicit or explicit) task cancellation cues results in the directed dismantling of recently instructed task rules. Our findings suggest that-even when cancelation cues are actively processed-such dismantling does not occur (Experiment 1-3) unless the no-longer relevant task rules are replaced by a new set of rules (Experiment 4). These findings and their implications are discussed in the broader context of action control and working memory. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Subject(s)
Cues , Memory, Short-Term , Humans , Memory, Short-Term/physiology
6.
Addict Behav Rep ; 14: 100365, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34938826

ABSTRACT

INTRODUCTION: Screen time apps that allow smartphone users to manage their screen time are assumed to combat negative effects of smartphone use. This study explores whether a social media restriction, implemented via screen time apps, has a positive effect on emotional well-being and sustained attention performance. METHODS: A randomized controlled trial (N = 76) was performed, exploring whether a week-long 50% reduction in time spent on mobile Facebook, Instagram, Snapchat and YouTube is beneficial to attentional performance and well-being as compared to a 10% reduction. RESULTS: Unexpectedly, several participants in the control group pro-actively reduced their screen time significantly beyond the intended 10%, dismantling our intended screen time manipulation. Hence, we analyzed both the effect of the original manipulation (i.e. treatment-as-intended), and the effect of participants' relative reduction in screen time irrespective of their condition (i.e. treatment-as-is). Neither analyses revealed an effect on the outcome measures. We also found no support for a moderating role of self-control, impulsivity or Fear of Missing Out. Interestingly, across all participants behavioral performance on sustained attention tasks remained stable over time, while perceived attentional performance improved. Participants also self-reported a decrease in negative emotions, but no increase in positive emotions. CONCLUSION: We discuss the implications of our findings in light of recent debates about the impact of screen time and formulate suggestions for future research based on important limitations of the current study, revolving among others around appropriate control groups as well as the combined use of both subjective and objective (i.e., behavioral) measures.

7.
J Exp Psychol Learn Mem Cogn ; 47(10): 1686-1704, 2021 Oct.
Article in English | MEDLINE | ID: mdl-32297789

ABSTRACT

Humans are able to anticipate abstract task demands and prepare attentional sets accordingly. A popular method to study this ability is to include explicit cues that signal the required level of cognitive control in conflict tasks (e.g., whether or not word meaning will correspond to the task-relevant font color in a Stroop task). Here, we demonstrate that this ability is more limited than assumed by most theories. Starting from a recent finding that implicit cues on the previous trial do not aid task performance, we demonstrate that these cues remain inefficient even when participants are explicitly instructed about their meaning, when the cue-stimulus interval is prolonged, or when the cues are deterministic and blocked (Experiments 1-4). In fact, the cues sometimes even impaired performance. Extending cue-information into the intertrial interval did not help (Experiment 5), and even though we replicated previous cueing effects using explicit cues in between trials in the vocal Stroop task (Experiment 7), this effect disappeared when using manual responses or presenting the cue in the preceding trial (Experiments 6, 8, and 9), and only benefited congruent responses when the intertrial interval was reduced (Experiment 10). Together, these findings point to important boundary conditions in cued control: The ability to prepare for control demands on a trial-by-trial basis is restricted to situations in which cues are presented alone, and where the task involves a nonarbitrary stimulus-response mapping. We discuss these findings in light of recent theories that emphasize the role of event boundaries and the value of cognitive control. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Subject(s)
Attention , Cues , Humans , Reaction Time , Stroop Test , Task Performance and Analysis
8.
Cereb Cortex ; 31(5): 2482-2493, 2021 03 31.
Article in English | MEDLINE | ID: mdl-33305807

ABSTRACT

Theoretical models explaining serial order processing link order information to specified position markers. However, the precise characteristics of position marking have remained largely elusive. Recent studies have shown that space is involved in marking serial position of items in verbal working memory (WM). Furthermore, it has been suggested, but not proven, that accessing these items involves horizontal shifts of spatial attention. We used continuous electroencephalography recordings to show that memory search in serial order verbal WM involves spatial attention processes that share the same electrophysiological signatures as those operating on the visuospatial WM and external space. Accessing an item from a sequence in verbal WM induced posterior "early directing attention negativity" and "anterior directing attention negativity" contralateral to the position of the item in mental space (i.e., begin items on the left; end items on the right). In the frequency domain, we observed posterior alpha suppression contralateral to the position of the item. Our results provide clear evidence for the involvement of spatial attention in retrieving serial information from verbal WM. Implications for WM models are discussed.


Subject(s)
Attention/physiology , Brain/physiology , Memory, Short-Term/physiology , Serial Learning/physiology , Adult , Electroencephalography , Evoked Potentials , Female , Humans , Male , Spatial Behavior/physiology , Young Adult
9.
Psychol Res ; 85(5): 1943-1954, 2021 Jul.
Article in English | MEDLINE | ID: mdl-32749535

ABSTRACT

We can sometimes efficiently pick up statistical regularities in our environment in the absence of clear intentions or awareness, a process typically referred to as implicit sequence learning. In the current study, we tried to address the question whether suggesting participants that there is nothing to learn can impact this form of learning. If a priori predictions or intentions to learn are important in guiding implicit learning, we reasoned that suggesting participants that there is nothing to learn in a given context should hamper implicit learning. We introduced participants to random contexts that indicated that there was nothing to learn, either implicitly (i.e., by presenting blocks of random trials in "Experiment 1"), or explicitly (i.e., by explicitly instructing them in "Experiment 2"). Next, in a subsequent learning phase, participants performed an implicit sequence learning task. We found that these implicit or explicit suggestions that 'there was nothing to learn' did not influence the emergence of implicit knowledge in the subsequent learning phase. Although these findings seem consistent with simple associative or Hebbian learning accounts of implicit sequence learning (i.e., not steered by predictions), we discuss potential limitations that should inform future studies on the role of a priori predictions in implicit learning.


Subject(s)
Knowledge , Learning , Humans , Reaction Time , Suggestion
10.
Ann N Y Acad Sci ; 1477(1): 91-99, 2020 10.
Article in English | MEDLINE | ID: mdl-32761632

ABSTRACT

The ability to memorize arbitrary sequences contributes to cognitive faculties like language and mathematics. Research suggests that in literate adults, serial order in verbal working memory (WM) is grounded in spatial attention and is mentally organized according to our reading habits, that is, from left-to-right in Western cultures. Currently, it is unknown whether spatialization is a consequence of literacy, or whether the ability already exists early in life but is shaped by literacy in "calibrating" the initial individual differences in the orientation of spatial coding. Here, we investigated the spatial coding of serial order in WM in 5-year-old children who did not yet enter formal literacy education. At the group level, no systematic spatial coding was observed. To investigate whether this absence was due to subjects with reliable but opposing effects, we determined the prevalence of spatial coding at the individual level. This analysis revealed that 36% of the children systematically associated serial order to space, with approximately half of them coding from left-to-right and the rest from right-to-left. These results indicate that a subgroup of preliterate children associate serial order with space and suggest that reading and writing experience calibrates the orientation of spatial coding with reading habits.


Subject(s)
Attention/physiology , Literacy , Memory, Short-Term/physiology , Space Perception/physiology , Child, Preschool , Female , Humans , Language , Male , Reading
11.
Ann N Y Acad Sci ; 1477(1): 20-33, 2020 10.
Article in English | MEDLINE | ID: mdl-32314419

ABSTRACT

Previous studies have shown that serial order in verbal working memory is spontaneously coded along the horizontal axis (i.e., the spatial positional association response codes (SPoARC) effect), with the initial items being associated with left and the last items being associated with right. These studies have led to the idea that when the cognitive system is confronted with a sequence of items processed verbally and semantically, it internally generates a spatial coordinate frame onto which memoranda can be bound to maintain their serial information. In this study, the interplay between internal and external spatial codes in the mind was investigated by testing the flexibility of the SPoARC effect. A verbal Sternberg probe detection task was used in which the displayed direction of the items during encoding (centrally, from left-to-right and from right-to-left) and the presentation rate (1- and 5-s/item) were manipulated. SPoARC effects were found in all conditions but were reversed in the right-to-left presentation condition. Follow-up analyses revealed no evidence of any spatial cost for the reversal; moreover, it was not influenced by the presentation rates. These findings suggest that space can be flexibly recruited for the spontaneous coding of serial order. The theoretical implications of these observations are discussed.


Subject(s)
Cognition/physiology , Memory, Short-Term/physiology , Space Perception/physiology , Adult , Female , Humans , Male , Semantics , Verbal Learning/physiology , Young Adult
12.
Psychol Res ; 84(8): 2079-2089, 2020 Nov.
Article in English | MEDLINE | ID: mdl-31197465

ABSTRACT

Recent proposals emphasize the role of learning in empirical markers of conflict adaptation. Some of these proposals are rooted in the assumption that contingency learning works not only on stimulus-response events but also on covert processes such as selective attention. In the present study, we explored how these learning processes may apply to trial-to-trial modulations of selective attention, mirroring the sequential nature of congruency sequence effects. Two groups of participants performed a four-choice Stroop task in which the color to which they responded on each trial acted as a probabilistic predictor either of the external response to be emitted on the next trial, or the congruency level (and therefore control demands) on the next trial. The results showed clear effects of sequence learning for external responses, but no evidence of learning about sequential stimulus-conflict associations. The implications of these results are discussed in relation to other learning-based phenomena of conflict adaptation and suggest that learning of stimulus-control associations is strongly constrained by event boundaries.


Subject(s)
Attention , Conflict, Psychological , Learning , Adaptation, Physiological , Adolescent , Adult , Female , Humans , Male , Stroop Test , Young Adult
13.
PLoS One ; 14(3): e0214762, 2019.
Article in English | MEDLINE | ID: mdl-30921438

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pone.0116469.].

14.
J Neuropsychol ; 13(1): 121-135, 2019 03.
Article in English | MEDLINE | ID: mdl-28714199

ABSTRACT

Parkinson's disease (PD) is a neurological disorder associated primarily with motor symptoms such as tremor, slowness of movement, and difficulties with gait and balance. Most patients take dopaminergic medication to improve their motor functions. Previous studies reported indications that such medication can impair higher cognitive functions (cf. dopamine overdose hypothesis). In the present study, we examined the effect of medication status on conflict adaptation. PD patients performed a Stroop task in which we manipulated the proportion of congruent and incongruent items, thereby allowing us to explore conflict adaptation. The use of mouse movements allowed us to examine the action dynamics of conflict adaptation in PD, and their sensitivity to dopaminergic medication. Each patient performed the same task twice: once without making changes to their regular medication regime, and once after overnight withdrawal from their medication. Results showed that medication improved mouse movements and alleviated motor symptoms. Moreover, patients' mouse movements were modulated as a function of the proportion congruency manipulation, revealing conflict adaptation in PD, which was unaffected by medication status. The present study extends earlier work on conflict adaptation in PD where reduced transient (trial-by-trial) conflict adaptation was observed ON compared to OFF medication (Duthoo et al., 2013, Neuropsychology, 27, 556). Our findings suggest that more sustained cognitive control processes may not be sensitive to dopamine overdose effects.


Subject(s)
Adaptation, Psychological/drug effects , Antiparkinson Agents/adverse effects , Antiparkinson Agents/therapeutic use , Conflict, Psychological , Dopamine Agonists/adverse effects , Dopamine Agonists/therapeutic use , Parkinson Disease/drug therapy , Parkinson Disease/psychology , Aged , Dopamine Agents , Female , Humans , Intelligence Tests , Male , Middle Aged , Motor Skills/drug effects , Neuropsychological Tests , Psychomotor Performance/drug effects , Stroop Test
16.
PLoS Comput Biol ; 14(8): e1006370, 2018 08.
Article in English | MEDLINE | ID: mdl-30142152

ABSTRACT

Optimal decision-making is based on integrating information from several dimensions of decisional space (e.g., reward expectation, cost estimation, effort exertion). Despite considerable empirical and theoretical efforts, the computational and neural bases of such multidimensional integration have remained largely elusive. Here we propose that the current theoretical stalemate may be broken by considering the computational properties of a cortical-subcortical circuit involving the dorsal anterior cingulate cortex (dACC) and the brainstem neuromodulatory nuclei: ventral tegmental area (VTA) and locus coeruleus (LC). From this perspective, the dACC optimizes decisions about stimuli and actions, and using the same computational machinery, it also modulates cortical functions (meta-learning), via neuromodulatory control (VTA and LC). We implemented this theory in a novel neuro-computational model-the Reinforcement Meta Learner (RML). We outline how the RML captures critical empirical findings from an unprecedented range of theoretical domains, and parsimoniously integrates various previous proposals on dACC functioning.


Subject(s)
Decision Making/physiology , Gyrus Cinguli/physiology , Animals , Brain Mapping/methods , Brain Stem/physiology , Cognition/physiology , Computer Simulation , Humans , Learning/physiology , Locus Coeruleus/physiology , Models, Theoretical , Reinforcement, Psychology , Reward , Ventral Tegmental Area/physiology
17.
PLoS One ; 13(5): e0197278, 2018.
Article in English | MEDLINE | ID: mdl-29771931

ABSTRACT

Previous studies indicated that cognitive conflict continues to bias actions even after a movement has been initiated. The present paper examined whether cognitive control also biases actions after movement initiation. To this end, we had participants perform a Stroop task in which we manipulated the item-specific proportion of (in)congruent trials (80% congruent vs. 20% congruent). Importantly, participants responded via mouse movements, allowing us to evaluate various movement parameters: initiation times, movement times, and movement accuracy. Results showed that mouse movements were faster and more accurate during congruent trials compared to incongruent trials. Moreover, we observed that this congruency effect was larger for 80% congruent compared to 20% congruent items, which reflects item-specific cognitive control. Notably, when responses were initiated very fast - rendering virtually no time for stimulus processing before movement onset - this item-specific control was observed only in movement times. However, for relatively slow initiated responses, item specific control was observed both in initiation and in movement times. These findings demonstrate that item-specific cognitive control biases actions before and after movement initiation.


Subject(s)
Conflict, Psychological , Motor Activity , Adolescent , Adult , Biomechanical Phenomena , Executive Function , Female , Hand , Humans , Inhibition, Psychological , Male , Reaction Time , Self-Control , Stroop Test , Young Adult
18.
Cognition ; 175: 96-100, 2018 06.
Article in English | MEDLINE | ID: mdl-29486378

ABSTRACT

The ability to maintain arbitrary sequences of items in the mind contributes to major cognitive faculties, such as language, reasoning, and episodic memory. Previous research suggests that serial order working memory is grounded in the brain's spatial attention system. In the present study, we show that the spatially defined mental organization of novel item sequences is related to literacy and varies as a function of reading/writing direction. Specifically, three groups (left-to-right Western readers, right-to-left Arabic readers, and Arabic-speaking illiterates) were asked to memorize random (and non-spatial) sequences of color patches and determine whether a subsequent probe was part of the memorized sequence (e.g., press left key) or not (e.g., press right key). The results showed that Western readers mentally organized the sequences from left to right, Arabic readers spontaneously used the opposite direction, and Arabic-speaking illiterates showed no systematic spatial organization. This finding suggests that cultural conventions shape one of the most "fluid" aspects of human cognition, namely, the spontaneous mental organization of novel non-spatial information.


Subject(s)
Concept Formation/physiology , Culture , Literacy , Memory, Short-Term/physiology , Reading , Space Perception/physiology , Adult , Attention/physiology , Female , Humans , Language , Male
19.
Psychiatry Res ; 257: 260-264, 2017 11.
Article in English | MEDLINE | ID: mdl-28783572

ABSTRACT

Cognitive control impairments may contribute strongly to the overall cognitive deficits observed in patients diagnosed with schizophrenia. In the current study we explore a specific cognitive control function referred to as conflict adaptation. Previous studies on conflict adaptation in schizophrenia showed equivocal results, and, moreover, were plagued by confounded research designs. Here we assessed for the first time conflict adaptation in schizophrenia with a design that avoided the major confounds of feature integration and stimulus-response contingency learning. Sixteen patients diagnosed with schizophrenia and sixteen healthy, matched controls performed a vocal Stroop task to determine the congruency sequence effect - a marker of conflict adaptation. A reliable congruency sequence effect was observed for both healthy controls and patients diagnosed with schizophrenia. These findings indicate that schizophrenia is not necessarily accompanied by impaired conflict adaptation. As schizophrenia has been related to abnormal functioning in core conflict adaptation areas such as anterior cingulate and dorsolateral prefrontal cortex, further research is required to better understand the precise impact of such abnormal brain functioning at the behavioral level.


Subject(s)
Adaptation, Psychological , Cognition Disorders/psychology , Conflict, Psychological , Schizophrenic Psychology , Adult , Case-Control Studies , Cognition , Female , Gyrus Cinguli/physiopathology , Humans , Male , Prefrontal Cortex/physiopathology , Stroop Test
20.
Psychol Res ; 81(3): 690-695, 2017 05.
Article in English | MEDLINE | ID: mdl-27000048

ABSTRACT

In a recent study, Kreitz et al. (Psychological Research 79:1034-1041, 2015) reported on a relationship between verbal working memory capacity and visuo-spatial attentional breadth. The authors hinted at attentional control to be the major link underlying this relationship. We put forward an alternative explanation by framing it within the context of a recent theory on serial order in memory: verbal item sequences entering in working memory are coded by adding a spatial context that can be derived from reading/writing habits. The observation by Kreitz et al. (Psychological Research 79:1034-1041, 2015) enriches this framework by suggesting that a larger visuo-spatial attentional breadth allows for internal coding of the verbal items in a more (spatially) distinct manner-thereby increasing working memory performance. As such, Kreitz et al. (Psychological Research 79:1034-1041, 2015) is the first study revealing a functional link between visuo-spatial attentional breadth and verbal working memory size, which strengthens spatial accounts of serial order coding in working memory.


Subject(s)
Attention , Memory, Short-Term , Humans , Reading
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