Natacha Deroost

Vrije Universiteit Brussel | VUB · Brain Body and Cognition

Recent studies emphasize a key role of controlled operations, such as set-shifting and inhibition, in the occurrence of freezing of gait (FOG) in Parkinson's disease (PD). However, FOG can also be characterized as a de-automatization disorder, showing impairments in both the execution and acquisition of automaticity. The observed deficits in automa...

Freezing of gait (FOG) is a very disabling symptom affecting up to half of the patients with Parkinson's disease (PD). Evidence is accumulating that FOG is caused by a complex interplay between motor, cognitive and affective factors, rather than being a pure motor phenomenon. In the current paper, we review the evidence on the specific role of cogn...

We investigated the influence of implicit learning on cognitive control. In a sequential Stroop task, participants implicitly learned a sequence placed on the color of the Stroop words. In Experiment 1, Stroop conflict was lower in sequenced than in random trials (learning-improved control). However, as these results were derived from an interactio...

Previous research demonstrated a positive effect of d-amphetamine on long-term verbal memory. An improvement in memory for contextual information is proposed as a possible mechanism underlying the d-amphetamine facilitation effect. A double blind, placebo controlled experiment was used to examine the processes involved in episodic memory affected b...

We investigated under which conditions sequence learning in a serial reaction time task can be based on perceptual learning. A replication of the study of Mayr (1996) confirmed perceptual and motor learning when sequences were learned concurrently. However, between-participants manipulations of the motor and perceptual sequences only supported moto...

The present meta-analysis investigated the impact of non-invasive stimulation, using transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) targeting the posterior cerebellum, on social and emotional mentalizing about others. Prior research has convincingly shown that the posterior cerebellum supports social and...

Transcranial Direct Current Stimulation (tDCS) has emerged as a promising tool for enhancing social cognition. The posterior cerebellum, which is part of the mentalizing network, has been implicated in social processes. In our combined tDCS-fMRI study, we investigated the effects of offline anodal cerebellar tDCS on activation in the cerebellum dur...

Social norms are pivotal in guiding social interactions. The current study investigated the potential contribution of the posterior cerebellum, a critical region involved in perceiving and comprehending the sequential dynamics of social actions, in detecting actions that either conform to or deviate from social norms. Participants engaged in a goal...

Spatial trajectory planning and execution in a social context play a vital role in our daily lives. To study this process, participants completed a goal-directed task involving either observing a sequence of preferred goals and self-planning a trajectory (Self Sequencing) or observing and reproducing the entire trajectory taken by others (Other Seq...

Implicit motor sequence learning (IMSL) is a cognitive function that is known to be associated with impaired motor function in Parkinson's disease (PD). We previously reported positive effects of transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) on IMSL in 11 individuals with PD with mild cognitive impairments (MCI),...

While interest grows in investigating sensory processing sensitivity (SPS), few studies have employed objective behavioural measures to directly explore the underlying attentional processing. The present study utilised two modified versions of the Emotional Attention Networks Test Integration (E-ANTI) to investigate whether and how emotion interact...

Conventional transcranial direct‐current stimulation (tDCS) delivered to the primary motor cortex (M1) has been shown to enhance implicit motor sequence learning (IMSL). Conventional tDCS targets M1 but also the motor association cortices (MAC), making the precise contribution of these areas to IMSL presently unclear. We aimed to address this issue...

Previous studies have identified that the posterior cerebellum, which plays a role in processing temporal sequences in social events, is consistently and robustly activated when we predict future action sequences based on personality traits (Haihambo Haihambo et al. Social Cognitive and Affective Neuroscience 17 (2), 241–251, 2022) and intentions (...

Although the human cerebellum has a surface that is about 80% of that of the cerebral cortex and has about four times as many neurons, its functional organization is still very much uncharted. Despite recent attempts to provide resting-state and task-based parcellations of the cerebellum, these two approaches lead to large discrepancies. This artic...

Studying autism might be a complex endeavor due to its clinical heterogeneity. Little is currently known about potential sex differences in autistic adults, especially regarding mentalizing and narrative coherence. In this study, male and female participants told a personal story about one of their most positive and most negative life events and pe...

Conventional transcranial direct-current stimulation (tDCS) delivered to the primary motor cortex (M1) has been shown to enhance implicit motor sequence learning (IMSL). Conventional tDCS targets M1 but also the motor association cortices (MAC), making the precise contribution of M1 to IMSL presently unclear. We aimed to address the roles of these...

Accumulating evidence shows that the posterior cerebellum is involved in mentalizing inferences of social events by detecting sequence information in these events, and building and updating internal models of these sequences. By applying anodal and sham cerebellar transcranial direct current stimulation (tDCS) on the posteromedial cerebellum of hea...

Humans read the minds of others to predict their actions and efficiently navigate social environments, a capacity called mentalizing. Accumulating evidence suggests that the cerebellum, especially Crus 1 and 2, and lobule IX are involved in identifying the sequence of others' actions. In the current study, we investigated the neural correlates that...

Research on the involvement of the cerebellum in social behavior and its relationship with social mentalizing has just begun. Social mentalizing is the ability to attribute mental states such as desires, intentions, and beliefs to others. This ability involves the use of social action sequences which are believed to be stored in the cerebellum. In...

BYLEMANS, T., et al. Mentalizing and narrative coherence in autistic adults: Cerebellar sequencing and prediction. NEUROSCI BIOBEHAV REV, 2022. - This review focuses on autistic adults and serves 4 purposes: (1) providing an overview of their difficulties regarding mentalizing (understanding others’ mental states) and narrative coherence (structure...

Prior studies suggest that the cerebellum contributes to the prediction of action sequences as well as the detection of social violations. In this dynamic causal modeling study, we explored the effective connectivity of the cerebellum with the cerebrum in processing social action sequences. A first model aimed to explore functional cerebello-cerebr...

Recent advances in social neuroscience have highlighted the critical role of the cerebellum and especially the posterior cerebellar Crus in social mentalizing (i.e., theory of mind). Research in the past 5 years has provided growing evidence supporting the view that the posterior cerebellum builds internal action models of our social interactions t...

Adults diagnosed with autism experience difficulties with understanding the mental states of others, or themselves (mentalizing) and with adequately sequencing personal stories (narrative coherence). Given that the posterior cerebellum is implicated in both skills, as well as in the etiology of autism, we developed a narrative sequencing and mental...

The posterior cerebellum contributes to dynamic social cognition by building representations and predictions about sequences in which social interactions typically take place. However, the extent to which violations of prior social expectations during human interaction activate the cerebellum remains largely unknown. The present study examined inco...

To study social sequence learning, earlier fMRI studies investigated the neural correlates of a novel Belief Serial Reaction Time task in which participants learned sequences of beliefs held by protagonists. The results demonstrated the involvement of the mentalizing network in the posterior cerebellum and cerebral areas (e.g., temporo-parietal jun...

Recent research has suggested that the posterior cerebellum encodes predictions and sequences of social actions, and also supports detecting inconsistent trait-implying actions of individuals as discussed by Pu et al. (2020, 2021). However, little is known about the role of the posterior cerebellum in detecting sequencing and inconsistencies by a g...

Recent research has indicated that the posterior cerebellum plays a crucial role in social cognition by encoding sequences of social actions. This study investigates its role in learning sequences of stereotype-implying actions by group members. We presented a set of five sentences that each described a group member who performed either stereotype-...

Background: Existing treatments for substance use disorders are often subject to drop-out or relapse. Transcranial direct current stimulation (tDCS) possibly has a positive effect on this problem. Aim: To give an updated qualitative review of existing studies investigating the clinical effects of transcranial direct current stimulation for peopl...

This study tests the hypothesis that the posterior cerebellum is involved in social cognition by identifying and automatizing sequences of social actions. We applied a belief serial reaction time task (Belief SRT task), which requires mentalizing about two protagonists’ beliefs about how many flowers they receive. The protagonists’ beliefs could ei...

The posterior cerebellum is responsible for the understanding and learning of sequences of actions by others, which are a prerequisite for social understanding. This study investigates this cerebellar function while navigating towards a goal in a social context. Participants undertook a novel social navigation task requiring them to memorize and su...

Objective: Various studies investigated implicit sequence learning in Parkinson’s disease (PD) by means of the traditional motor Serial Reaction Time (SRT) task and found a general pattern of impaired sequence learning. However, as perceptual and motor sequences of the SRT-task were correlated in previous studies, implicit sequential knowledge acqu...

Can we predict the future by reading others´ minds? This study explores whether attributing others' personality traits facilitate predictions about their future actions and the temporal order of these future actions. Prior evidence demonstrated that the posterior cerebellar Crus is involved in identifying the temporal sequence of social actions and...

Can we predict the future by reading others´ minds? This study explores whether attributing others' personality traits facilitate predictions about their future actions and the temporal order of these future actions. Prior evidence demonstrated that the posterior cerebellar Crus is involved in identifying the temporal sequence of social actions and...

Recent studies have documented the involvement of the posterior cerebellar Crus (I & II) in social mentalizing, when sequences play a critical role. We investigated for the first time implicit learning of belief sequences. We created a novel task in which true and false beliefs of other persons were alternated in an adapted serial reaction time (SR...

Implicit motor sequence learning (IMSL) is a cognitive function that is known to be directly associated with impaired motor function in Parkinson's disease (PD). Research on healthy young participants shows the potential for transcranial direct current stimulation (tDCS), a noninvasive brain stimulation technique, over the primary motor cortex (M1)...

To investigate whether people can implicitly learn regularities in a social context, we developed a new implicit sequence learning task combining elements from classic false belief and serial reaction time tasks. Participants learned that protagonists were offered flowers at four locations. The protagonists' beliefs concerning the flowers were true...

Implicit motor sequence learning (IMSL) is affected in Parkinson's disease (PD). Research in healthy young participants shows the potential for transcranial direct‐current stimulation (tDCS) over the primary motor cortex (M1) to enhance IMSL. In PD, only null effects have been reported to date. We determined concurrent, short‐term, and long‐term ef...

An ALE meta-analysis focused on the serial reaction time task published in NeuroImage (Janacsek et al., 2019) demonstrated consistent activation of the basal ganglia across neuroimaging studies featuring sequence > random block contrasts and no consistent cerebellar activation. To enable valid conclusions regarding the role of the cerebellum in thi...

We investigated an attention bias (AB) for emotional faces in emotional eating (EM). A group obtaining a low score (n = 18) on the Emotional eating scale of the Dutch Eating Behavior Questionnaire and a high scoring group (n = 23) completed the Exogenous Cueing Task (ECT). The ECT experiment measured their reaction times to the location of a target...

We examined the role of sequence awareness in a pure perceptual sequence learning design. Participants had to react to the target's colour that changed according to a perceptual sequence. By varying the mapping of the target's colour onto the response keys, motor responses changed randomly. The effect of sequence awareness on perceptual sequence le...

Objectives: Parkinson's disease (PD) has been associated with impaired motor sequence learning (also known as procedural learning). In the current study, we determined the potential of anodal transcranial direct current stimulation delivered over the primary motor cortex to promote the acquisition of sequential movement in a large sample of patient...

We investigated the implicit preference in terms of food portion in obesity using the affective priming paradigm. Primes representing different portions of fast food (small, medium, large) were used to assess participants' readiness to respond to a positive or negative target word. A self-reported affective rating scale of food portion and a portio...

In the attentional control theory of anxiety, Eysenck, Derakshan, Santos, and Calvo (2007) propose that worrying depletes cognitive resources, thereby reducing the efficiency of cognitive task performance in anxious participants. However, most of the research supporting this hypothesis does not directly address the contribution of worrying to the a...

Despite the clinical relevance of worrying, its underlying cognitive mechanisms remain poorly understood. Eysenck postulates that high-worriers’ long term memory is characterized by tightly organized clusters with negatively valenced worry-related information, causing this information to be more readily accessible. Based on this premise, we expect...

This study aims to investigate whether attentional biases typically associated with depression and anxiety already exist on a sub-clinical level. A transdiagnostic characteristic, both affective disorders have in common at a sub-clinical level, is persistent negative thinking (PNT), called rumination in depression and worrying in anxiety disorders....

The effect of attentional load on implicit sequence learning in children and young adults

In the current study, we assessed whether visuospatial sequence knowledge is retained over 24 hours and whether this retention is dependent on the occurrence of eye movements. Participants performed two sessions of a serial reaction time (SRT) task in which they had to manually react to the identity of a target letter pair presented in one of four...

Background and and objectives: Learning and memory impairment is one of the most persistent cognitive symptoms in multiple sclerosis (MS). In order to fine-tune rehabilitation interventions, a thorough understanding of the specific involvement of implicit and explicit learning processes underlying this impairment is required. To this aim, we determ...

We investigated the effect of a secondary task on implicit sequence learning in children and young adults. A serial reaction time (SRT) task was administered to 8-to-10 year old children and 18-to-22 year old adults. Participants reacted to the location of a target presented in one of four locations on the screen with a spatially corresponding resp...

We investigated the influence of attentional demands on sequence-specific learning by means of the serial reaction time task (Nissen and Bullemer, 1987) in young (age 18–25) and aged (age 55–75) adults. Participants had to respond as fast as possible to a stimulus presented in one of four horizontal locations by pressing a key corresponding to the...

Persistent negative thought is a hallmark feature of both major depressive disorder and generalized anxiety disorder. Despite its clinical significance, little is known about the underlying mechanisms of persistent negative thought. Recent studies suggest that reduced cognitive control might be an explanatory factor. We investigated the association...

Objective: Freezing of gait (FOG) in Parkinson's disease (PD) may involve specific impairments in acquiring automaticity under working memory load. This study examined whether implicit sequence learning, with or without a secondary task, is impaired in patients with FOG. Method: Fourteen freezers (FRs), 14 nonfreezers (nFRs), and 14 matched heal...

We examined perceptual sequence learning by means of an adapted serial reaction time task in which eye movements were unnecessary for performing the sequence learning task. Participants had to respond to the identity of a target letter pair ("OX" or "XO") appearing in one of four locations. On the other locations, similar distractor letter pairs ("...

This study assessed whether real-life stimulus material can elicit conscious and unconscious priming. A typical masked priming paradigm was used, with brand logo primes. We used a rigorous method to assess participants' awareness of the subliminal information. Our results show that shortly presented and masked brand logos (e.g., logo of McDonald's)...

We investigated response activation and suppression processes in Parkinson's disease patients with freezing of gait (FOG). Fourteen freezers, 14 nonfreezers, and 14 matched healthy controls performed the attention network task (ANT) and the Stroop task. The former task has more stimulus-response overlap and is expected to elicit stronger irrelevant...

We investigated the automaticity of implicit sequence learning by varying perceptual load in a pure perceptual sequence learning paradigm. Participants responded to the randomly changing identity of a target, while the irrelevant target location was structured. In Experiment 1, the target was presented under low or high perceptual load during train...

Freezing of gait (FOG) in Parkinson disease (PD) may involve executive dysfunction. This study examined whether executive functioning and attention are more affected in patients with FOG compared with those without and determined whether these processes are influenced by anti-Parkinson medication. A total of 11 PD patients with FOG, 11 without FOG,...

On successive trials, repetitions of irrelevant information often tend to reduce congruency effects as compared to alternations of irrelevant information. The preferred explanation for this congruency modulation is the sustained-suppression hypothesis, suggesting that suppression of the irrelevant information on a given trial perseveres into the su...

Repeating irrelevant information on successive trials tends to temporarily reduce congruency effects. Despite general explanations extending to all stimulus types, this congruency modulation is mainly observed when using spatial irrelevant information. For nonspatial irrelevant information, the modulation is inconsistent. The present study tested t...

Smaller Simon effects when stimulus locations are repeated on successive trials rather than alternated have been explained by the attention shift hypothesis, suggesting that shifts of attention result in interfering response codes. We investigated whether the attention shift hypothesis can also explain smaller flanker effects for repeated flankers...

The improvement of long-term retention of verbal memory after an acute administration of D-amphetamine in recall and recognition tasks has been ascribed to an influence of the drug on memory consolidation. Because recent research has demonstrated that intermediate testing is of overriding importance for retention, we investigated whether D-amphetam...

In two experiments with the serial reaction time task the effect of response selection processes on sequence learning was examined by manipulating stimulus-response compatibility between training groups. In Experiment 1 participants were first trained with either compatible or incompatible stimulus-response mapping. Then, to dissociate effects on s...

We examined the influence of task complexity on implicit sequence learning in secondary-school-aged children with developmental dyslexia (DD). This was done to determine whether automatization problems in reading extend to the automatization of all skill and depend on the complexity of the to-be-learned skill. A total of 28 dyslexic children betwee...

In two experiments, we investigated the hypothesis of Rowland and Shanks (2006a) that sequence learning of relevant information is resistant to variations in perceptual load. Under conditions of increased selection difficulty, participants incidentally learned a sequence of targets presented together with three distractors. Target and distractors w...

We investigated the influence of the level of cognitive functioning on sequence-specific learning in Parkinson's disease (PD). This was done by examining the relationship between the scales for outcomes in Parkinson's disease-cognition [SCOPA-COG, Marinus, J., Visser, M., Verwey, N. A., Verhey, F. R. J., Middelkoop, H. A. M.,Stiggelbout, A., et al....

We investigated negative priming (NP) in sequence learning, as demonstrated by Cock, Berry, and Buchner (2002). The NP effect in sequence learning refers to the observation that Serial Reaction Time performance becomes impaired when participants respond to a sequence they were previously ignoring. In Experiment 1, we established a NP effect with a...

We investigated the contributions of the sequences of effectors and response locations to probabilistic sequence learning in the serial reaction time task by means of bimanual transfer. Participants, trained with the dominant hand, were either required to maintain responding with the dominant hand after transfer or to switch to the nondominant hand...