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1.
Sci Rep ; 13(1): 5379, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37009782

RESUMO

It seems natural that motor responses unfold smoothly and that we are able to easily concatenate different components of movements to achieve goal-directed actions. Theoretical frameworks suggest that different motor features have to be bound to each other to achieve a coherent action. Yet, the nature of the "glue" (i.e., bindings) between elements constituting a motor sequence and enabling a smooth unfolding of motor acts is not well understood. We examined in how far motor feature bindings are affected by reward magnitude or the effects of an unsigned surprise signal. We show that the consistency of action file binding strength is modulated by unsigned surprise, but not by reward magnitude. On a conceptual and theoretical level, the results provide links between frameworks, which have until now not been brought into connection. In particular, theoretical accounts stating that only the unexpectedness (surprisingness) is essential for action control are connected to meta-control accounts of human action control.


Assuntos
Movimento , Recompensa , Humanos
2.
J Cogn Enhanc ; 6(4): 463-477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36373033

RESUMO

Neurofeedback (NF) is an important treatment for attention deficit/hyperactivity disorder (ADHD). In ADHD, cognitive control deficits pose considerable problems to patients. However, NF protocols are not yet optimized to enhance cognitive control alongside with clinical symptoms, partly because they are not driven by basic cognitive neuroscience. In this study, we evaluated different EEG theta and/or beta frequency band NF protocols designed to enhance cognitive control. Participants were n = 157 children and adolescents, n = 129 of them were patients with ADHD (n = 28 typically developing (TD) controls). Patients with ADHD were divided into five groups in the order of referral, with four of them taking part in different NF protocols systematically varying theta and beta power. The fifth ADHD group and the TD group did not undergo NF. All NF protocols resulted in reductions of ADHD symptoms. Importantly, only when beta frequencies were enhanced during NF (without any theta regulation or in combination with theta upregulation), consistent enhancing effects in both response inhibition and conflict control were achieved. The theta/beta NF protocol most widely used in clinical settings revealed comparatively limited effects. Enhancements in beta band activity are key when aiming to improve cognitive control functions in ADHD. This calls for a change in the use of theta/beta NF protocols and shows that protocols differing from the current clinical standard are effective in enhancing important facets of cognitive control in ADHD. Further studies need to examine regulation data within the neurofeedback sessions to provide more information about the mechanisms underlying the observed effects. Supplementary Information: The online version contains supplementary material available at 10.1007/s41465-022-00255-6.

3.
J Neurophysiol ; 128(3): 543-555, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35894437

RESUMO

Even simple actions like opening a door require integration/binding and flexible reactivation of different motor elements. Yet, the neural mechanisms underlying the processing of such "embedded response plans" are largely elusive, despite theoretical frameworks, such as the theory of event coding, describing the involved cognitive processes. In a sample of n = 40 healthy participants, we combine time-frequency decomposition and various beamforming methods to examine the neurophysiological dynamics of such action plans, with special emphasis on the interplay of theta and beta frequency activity during the processing of these plans. We show that the integration and rule-guided reactivation of embedded response plans is modulated by a complex interplay of theta and beta activity. Pretrial beta-band activity (BBA) is related to different functional neuroanatomical structures that are activated in a consecutive fashion. Enhanced preparatory activity is positively associated with higher binding-related BBA in the precuneus/parietal areas, indicating that activity in the precuneus/parietal cortex facilitates the execution of an embedded action sequence. Increased preparation subsequently leads to reduced working memory retrieval demands. A cascading pattern of interactions between pretrial and within-trial activity indicates the importance of preparatory brain activity. The study shows that there are multiple roles of beta and theta oscillations associated with different functional neuroanatomical structures during the integration and reactivation of motor elements during actions.NEW & NOTEWORTHY Even simple actions like opening a door require integration/binding and flexible reactivation of different motor elements. Yet, the neural mechanisms underlying the processing of such "embedded response plans" are largely elusive. The study shows that there are multiple roles of beta and theta oscillations associated with different functional neuroanatomical structures during the integration and reactivation of motor elements during actions.


Assuntos
Ritmo beta , Lobo Frontal , Lobo Parietal , Desempenho Psicomotor , Ritmo Teta , Ritmo beta/fisiologia , Eletroencefalografia , Lobo Frontal/fisiologia , Humanos , Memória de Curto Prazo/fisiologia , Lobo Parietal/fisiologia , Desempenho Psicomotor/fisiologia , Ritmo Teta/fisiologia
4.
J Neurophysiol ; 125(4): 1382-1395, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33689490

RESUMO

Performing a goal-directed movement consists of a chain of complex preparatory mechanisms. Such planning especially requires integration (or binding) of various action features, a process that has been conceptualized in the "theory of event coding." Theoretical considerations and empirical research suggest that these processes are subject to developmental effects from adolescence to adulthood. The aim of the present study was to investigate age-related modulations in action feature binding processes and to shed light on underlying neurophysiological development from preadolescence to early adulthood. We examined a group of healthy participants (n = 61) between 10 and 30 yr of age, who performed a task that requires a series of bimanual response selections in an embedded paradigm. For an in-depth analysis of the underlying neural correlates, we applied EEG signal decomposition together with source localization analyses. Behavioral results across the whole group did not show binding effects in reaction times but in intraindividual response variability. From age 10 to 30 yr, there was a decrease in reaction times and reaction time variability but no age-related effect in action file binding. The latter were corroborated by Bayesian data analyses. On the brain level, the developmental effects on response selection were associated with activation modulations in the superior parietal cortex (BA7). The results show that mechanisms of action execution and speed, but not those of action feature binding, are subject to age-related changes between the age of 10 and 30 yr.NEW & NOTEWORTHY Different aspects of an action need to be integrated to allow smooth unfolding of behavior. We examine developmental effects in these processes and show that mechanisms of action execution and speed, but not those of action feature binding, are subject to age-related changes between the age of 10 and 30 yr.


Assuntos
Desenvolvimento Humano/fisiologia , Atividade Motora/fisiologia , Lobo Parietal/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adolescente , Adulto , Fatores Etários , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
5.
Am J Dermatopathol ; 34(7): 699-705, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22481495

RESUMO

Self-healing juvenile cutaneous mucinosis (SHJCM) is a rare disorder of unknown origin, which occurs in children in good health. It is characterized by the multiplication of transient cutaneous papules and nodules, mainly located on the head and periarticular areas that spontaneously resolve. Histological features of SHJCM have been well described; therefore, the diagnosis is usually made easily when papules are biopsied. We report a series of 3 new cases of SHJCM presenting mainly with nodular lesions. Histological examination of these nodules showed either lesions consistent with nodular or proliferative fasciitis or nonspecific panniculitis. Mucinous deposits were present but often inconspicuous, so could be disregarded. We wanted to emphasize this misleading presentation because a biopsy for histological examination is always mandatory in cases of proliferating nodules to rule out malignant tumors. Therefore, the diagnosis always requires discussion between pathologists and clinicians to rapidly reassure the parents and avoid inappropriate therapy.


Assuntos
Proliferação de Células , Erros de Diagnóstico/prevenção & controle , Mucinoses/patologia , Mucinas/análise , Neoplasias Cutâneas/patologia , Pele/patologia , Biomarcadores/análise , Biópsia , Pré-Escolar , Fasciite/etiologia , Fasciite/patologia , Humanos , Imuno-Histoquímica , Lactente , Masculino , Mucinoses/complicações , Mucinoses/metabolismo , Paniculite/etiologia , Paniculite/patologia , Valor Preditivo dos Testes , Remissão Espontânea , Pele/química , Fatores de Tempo
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