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1.
Gen Psychiatr ; 37(3): e101486, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38859926

RESUMO

Background: Attention-deficit/hyperactivity disorder (ADHD) is one of the most frequently diagnosed psychiatric conditions in children and adolescents. Although the symptoms appear to be well described, no coherent conceptual mechanistic framework integrates their occurrence and variance and the associated problems that people with ADHD face. Aims: The current study proposes that altered event segmentation processes provide a novel mechanistic framework for understanding deficits in ADHD. Methods: Adolescents with ADHD and neurotypically developing (NT) peers watched a short movie and were then asked to indicate the boundaries between meaningful segments of the movie. Concomitantly recorded electroencephalography (EEG) data were analysed for differences in frequency band activity and effective connectivity between brain areas. Results: Compared with their NT peers, the ADHD group showed less dependence of their segmentation behaviour on social information, indicating that they did not consider social information to the same extent as their unaffected peers. This divergence was accompanied by differences in EEG theta band activity and a different effective connectivity network architecture at the source level. Specifically, NT adolescents primarily showed error signalling in and between the left and right fusiform gyri related to social information processing, which was not the case in the ADHD group. For the ADHD group, the inferior frontal cortex associated with attentional sampling served as a hub instead, indicating problems in the deployment of attentional control. Conclusions: This study shows that adolescents with ADHD perceive events differently from their NT peers, in association with a different brain network architecture that reflects less adaptation to the situation and problems in attentional sampling of environmental information. The results call for a novel conceptual view of ADHD, based on event segmentation theory.

2.
Hum Brain Mapp ; 45(8): e26719, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38826009

RESUMO

Gilles de la Tourette syndrome (GTS) is a disorder characterised by motor and vocal tics, which may represent habitual actions as a result of enhanced learning of associations between stimuli and responses (S-R). In this study, we investigated how adults with GTS and healthy controls (HC) learn two types of regularities in a sequence: statistics (non-adjacent probabilities) and rules (predefined order). Participants completed a visuomotor sequence learning task while EEG was recorded. To understand the neurophysiological underpinnings of these regularities in GTS, multivariate pattern analyses on the temporally decomposed EEG signal as well as sLORETA source localisation method were conducted. We found that people with GTS showed superior statistical learning but comparable rule-based learning compared to HC participants. Adults with GTS had different neural representations for both statistics and rules than HC adults; specifically, adults with GTS maintained the regularity representations longer and had more overlap between them than HCs. Moreover, over different time scales, distinct fronto-parietal structures contribute to statistical learning in the GTS and HC groups. We propose that hyper-learning in GTS is a consequence of the altered sensitivity to encode complex statistics, which might lead to habitual actions.


Assuntos
Eletroencefalografia , Síndrome de Tourette , Humanos , Síndrome de Tourette/fisiopatologia , Masculino , Adulto , Feminino , Adulto Jovem , Aprendizagem/fisiologia , Desempenho Psicomotor/fisiologia , Pessoa de Meia-Idade , Aprendizagem por Probabilidade
3.
Commun Biol ; 7(1): 759, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909084

RESUMO

That younger individuals perceive the world as moving slower than adults is a familiar phenomenon. Yet, it remains an open question why that is. Using event segmentation theory, electroencephalogram (EEG) beamforming and nonlinear causal relationship estimation using artificial neural network methods, we studied neural activity while adolescent and adult participants segmented a movie. We show when participants were instructed to segment a movie into meaningful units, adolescents partitioned incoming information into fewer encapsulated segments or episodes of longer duration than adults. Importantly, directed communication between medial frontal and lower-level perceptual areas and between occipito-temporal regions in specific neural oscillation spectrums explained behavioral differences between groups. Overall, the study reveals that a different organization of directed communication between brain regions and inefficient transmission of information between brain regions are key to understand why younger people perceive the world as moving slow.


Assuntos
Eletroencefalografia , Humanos , Adolescente , Masculino , Feminino , Adulto , Adulto Jovem , Encéfalo/fisiologia , Percepção de Movimento/fisiologia , Redes Neurais de Computação
4.
Brain Commun ; 6(2): fcae092, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562308

RESUMO

Gilles de la Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics. It is associated with enhanced processing of stimulus-response associations, including a higher propensity to learn probabilistic stimulus-response contingencies (i.e. statistical learning), the nature of which is still elusive. In this study, we investigated the hypothesis that resting-state theta network organization is a key for the understanding of superior statistical learning in these patients. We investigated the graph-theoretical network architecture of theta oscillations in adult patients with Gilles de la Tourette syndrome and healthy controls during a statistical learning task and in resting states both before and after learning. We found that patients with Gilles de la Tourette syndrome showed a higher statistical learning score than healthy controls, as well as a more optimal (small-world-like) theta network before the task. Thus, patients with Gilles de la Tourette syndrome had a superior facility to integrate and evaluate novel information as a trait-like characteristic. Additionally, the theta network architecture in Gilles de la Tourette syndrome adapted more to the statistical information during the task than in HC. We suggest that hyper-learning in patients with Gilles de la Tourette syndrome is likely a consequence of increased sensitivity to perceive and integrate sensorimotor information leveraged through theta oscillation-based resting-state dynamics. The study delineates the neural basis of a higher propensity in patients with Gilles de la Tourette syndrome to pick up statistical contingencies in their environment. Moreover, the study emphasizes pathophysiologically endowed abilities in patients with Gilles de la Tourette syndrome, which are often not taken into account in the perception of this common disorder but could play an important role in destigmatization.

5.
Cortex ; 171: 26-39, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37977111

RESUMO

Individuals organize the evolving stream of events in their environment by partitioning it into discrete units. Event segmentation theory (EST) provides a cognitive explanation for the process of this partitioning. Critically, the underlying time-resolved neural mechanisms are not understood, and thus a central conceptual aspect of how humans implement this central ability is missing. To gain better insight into the fundamental temporal dynamics of event segmentation, EEG oscillatory activity was measured while participants watched a narrative video and partitioned the movie into meaningful segments. Using EEG beamforming methods, we show that theta, alpha, and beta band activity in frontal, parietal, and occipital areas, as well as their interactions, reflect critical elements of the event segmentation process established by EST. In sum, we see a mechanistic temporal chain of processes that provides the neurophysiological basis for how the brain partitions and structures continuously evolving scenes and points to an integrated system that organizes the various subprocesses of event segmentation. This study thus integrates neurophysiology and cognitive theory to better understand how the human brain operates in rather variable and unpredictable situations. Therefore, it represents an important step toward studying neurophysiological dynamics in ecologically valid and naturalistic settings and, in doing so, addresses a critical gap in knowledge regarding the temporal dynamics of how the brain structures natural scenes.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletroencefalografia/métodos
6.
Int J Psychol ; 59(1): 172-183, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37866816

RESUMO

In the context of the COVID-19 pandemic, across six correlational studies in four different countries (total N = 4937), we examined the link between citizens' anger with and admiration for the government's actions and decisions (i.e., system-based anger and admiration) and engagement in preventive behaviour. The internal meta-analyses showed that individuals who admired the government's actions were more likely to adopt personal hygiene and social distancing behaviour. Yet, the link between emotions and preventive behaviour differed concerning the target of emotions, especially for anger. Specifically, anger about restrictions imposed by the government was negatively related to preventive behaviours, but this relationship was not significant when the target of anger was the government's overall handling of the pandemic. Our findings emphasise the importance of citizens' emotions and the targets of those emotions during the crisis.


Assuntos
COVID-19 , Humanos , Pandemias , Autorrelato , Ira , Governo
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