Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64.768
Filtrar
1.
PLoS Comput Biol ; 16(8): e1008081, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32750070

RESUMO

We rarely experience difficulty picking up objects, yet of all potential contact points on the surface, only a small proportion yield effective grasps. Here, we present extensive behavioral data alongside a normative model that correctly predicts human precision grasping of unfamiliar 3D objects. We tracked participants' forefinger and thumb as they picked up objects of 10 wood and brass cubes configured to tease apart effects of shape, weight, orientation, and mass distribution. Grasps were highly systematic and consistent across repetitions and participants. We employed these data to construct a model which combines five cost functions related to force closure, torque, natural grasp axis, grasp aperture, and visibility. Even without free parameters, the model predicts individual grasps almost as well as different individuals predict one another's, but fitting weights reveals the relative importance of the different constraints. The model also accurately predicts human grasps on novel 3D-printed objects with more naturalistic geometries and is robust to perturbations in its key parameters. Together, the findings provide a unified account of how we successfully grasp objects of different 3D shape, orientation, mass, and mass distribution.


Assuntos
Força da Mão/fisiologia , Modelos Biológicos , Desempenho Psicomotor/fisiologia , Adulto , Biologia Computacional , Feminino , Mãos/fisiologia , Humanos , Masculino , Torque , Adulto Jovem
2.
Medicine (Baltimore) ; 99(27): e20720, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629646

RESUMO

Dual-task interference (DTI) is a decreased performance when conducting 2 tasks simultaneously, such as cognitive and motor tasks. This study aimed to identify the DTI-related factors with individually computerized interference and analyze the relative implications of decreasing DTI in healthy farmers.It followed 3 computerized experiments:The reaction time of correct releases (CRT) of BT1 in all tasks was measured, and the CRT ratios of DT were divided by the CRT values from CT and MT to obtain the DTI value. CRT during CT and MT was decreased compared to that during DT. The interference by CT (CRT of DT/CRT of MT × 100, CTI) was increased compared to the interference by MT (CRT of DT/CRT of CT×100, MTI). Additionally, comprehensive baseline characteristics, body composition, psycho-cognitive, and physical factors were assessed.Of a total of 54 participants, 16 are males (67.2 ±â€Š8.9 years) and 38 females (62.5 ±â€Š6.6 years). CTI showed significant correlations with age (r = 0.436, P < .001), farming period (r = 0.290, P = .033), score of the Mini-Mental State Examination in the Korean version of CERAD Assessment Packet (r = -0.329, P = .015), CRT of the Go/No-Go test (r = 0.67, P < .001), score of the short physical performance battery (r = -0.304, P = .026), and time of the timed up and go test (r = 0.364, P = .007). Regression analysis showed that the CRT of the Go/No-Go test (ß = 0.558, P < .001) was the most explanatory factors for CTI.Based on the individualized DTI values quantified, interference during cognitive task was mostly related to CRT of Go/No-Go test, reflecting the attentional level. These results could suggest strategies for the active attentional training to reduce DTI and passive simplification and modification of lifestyles.


Assuntos
Atenção , Fazendeiros/psicologia , Desempenho Psicomotor , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , República da Coreia
3.
Nat Commun ; 11(1): 3341, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620746

RESUMO

The oculomotor system keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile, frequency discrimination task enabled us to test whether the oculomotor system shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. We find that microsaccades are inhibited prior to tactile targets and more so for constant than variable intervals, revealing a tight crossmodal link between tactile temporal expectation and oculomotor action. These findings portray oculomotor freezing as a marker of crossmodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation are associated with reduced task performance, suggesting that oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a crossmodal coupling between tactile perception and oculomotor action.


Assuntos
Movimentos Oculares/fisiologia , Desempenho Psicomotor/fisiologia , Percepção do Tempo/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Músculos Oculomotores/inervação , Músculos Oculomotores/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Adulto Jovem
4.
Percept Mot Skills ; 127(5): 960-979, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32611226

RESUMO

As the Covid 19 crisis has revealed, the internet is a first-line tool for learning critical health-related information. However, internet searches are a complex and dynamic process that can be fraught with subtleties and potential error. The mechanics of searching for and using electronic health (eHealth) information is ostensibly cognitively demanding; yet we know little about the role of neurocognitive abilities in this regard. Fifty-six young adults completed two naturalistic eHealth search tasks: fact-finding (eHealth Fact) and symptom-diagnosis (eHealth Search). Participants also completed neurocognitive tests of attention, psychomotor speed, learning/memory, and executive functions. Shorter eHealth symptom-diagnosis search time was related to better executive functions, while better eHealth symptom-diagnosis search accuracy was related to better episodic and prospective memory. In contrast, neither eHealth Fact search time nor its accuracy were related to any of the neurocognitive measures. Our findings suggest a differential relationship between neurocognitive abilities and eHealth search behaviors among young adults such that higher-order abilities may be implicated in eHealth searches requiring greater synthesis of information. Future work should examine the cognitive architecture of eHealth search in persons with neurocognitive disorders, as well as that of other aspects of eHealth search behaviors (e.g., search term generation, website reliability, and decision-making).


Assuntos
Aptidão , Atenção , Cognição , Informação de Saúde ao Consumidor , Função Executiva , Comportamento de Busca de Informação , Internet , Memória , Adolescente , Adulto , Betacoronavirus , Infecções por Coronavirus , Tomada de Decisões , Feminino , Comportamentos Relacionados com a Saúde , Letramento em Saúde , Humanos , Aprendizagem , Masculino , Pandemias , Pneumonia Viral , Desempenho Psicomotor , Telemedicina , Adulto Jovem
5.
PLoS One ; 15(7): e0235552, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645114

RESUMO

The aim of the study is to compare the spatial working memory and visual perception between children with autism spectrum disorder (ASD) and typically developing control (TDC). Furthermore, this study validated whether this impairment was a feature of autism in general population with different autism-like traits (ALTs). This study contains two parts: case-control study and community population study. The ASD group and the control group were enlisted voluntarily (ASD group, n = 52; control group, n = 32). In the population study, we recruited 2994 children. Based on the scores of Autism Spectrum Quotient (AQ), children were divided into two groups (higher ALTs n = 122, lower ALTs n = 122). The participants completed the cognition tasks focusing on spatial working memory, visual-motor integration, and Intelligence. Analysis of covariance (ANCOVA) was conducted, with potential confounders IQ, age, and gender were controlled. Pearson correlations were computed by controlling the IQ and age as covariate to better understand the relations between visual perception, spatial working memory, and autism-like traits. In the case-control study, the results of cognition tasks focusing on the spatial working memory and visual perception indicated underperformance in children with ASD. In the community population study, we found that individuals with higher ALTs performed worse than children with lower ALTs in spatial working memory. Pearson correlation analysis suggested that a correlation between SWM total errors and visual perception was identified both in the children with ASD and in community population (ASD group, r = -0.592, p<0.001; general population, r = -0.201, p = 0.003). It suggested that spatial working memory deficit was a characteristic of autism, and may be distributed across the general population. Furthermore, we speculated a correlation between spatial working memory and visual perception in children with ASD and in general population.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Memória de Curto Prazo , Memória Espacial , Percepção Visual , Adolescente , Transtorno do Espectro Autista/psicologia , Criança , Feminino , Humanos , Inteligência , Masculino , Desempenho Psicomotor
6.
Nat Commun ; 11(1): 3318, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620879

RESUMO

Decision-making is guided by memories of option values. However, retrieving items from memory renders them malleable. Here, we show that merely retrieving values from memory and making a choice between options is sufficient both to induce changes to stimulus-reward associations in the hippocampus and to bias future decision-making. After allowing participants to make repeated choices between reward-conditioned stimuli, in the absence of any outcome, we observe that participants prefer stimuli they have previously chosen, and neglect previously unchosen stimuli, over otherwise identical-valued options. Using functional brain imaging, we show that decisions induce changes to hippocampal representations of stimulus-outcome associations. These changes are correlated with future decision biases. Our results indicate that choice-induced preference changes are partially driven by choice-induced modification of memory representations and suggest that merely making a choice - even without experiencing any outcomes - induces associative plasticity.


Assuntos
Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Adulto , Algoritmos , Viés , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Condicionamento Clássico/fisiologia , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Desempenho Psicomotor/fisiologia , Recompensa , Adulto Jovem
8.
Exp Psychol ; 67(2): 77-87, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32729404

RESUMO

The intriguing interplay between acute stress physiology and cognitive processes has long been noted. However, while stress-induced release of glucocorticoids has repeatedly been shown to impact brain mechanisms underlying cognition and memory, less experimental research addressed the effects of stress-induced central sympathetic nervous system (SNS) activation on cognitive performance. Moreover, despite the long-standing notion that the way performance is modulated by arousal may crucially depend on task complexity, mechanistic research demonstrating a direct, causal influence of altered SNS activity is scarce. Twelve healthy men participated in a placebo-controlled, pharmacologic dose-response study involving three within-subject assessments (1-week intervals). Subjective and objective indices of SNS activity as well as reaction time (RT) in three different tasks varying in cognitive demand (simple RT, choice RT, and verbal RT in complex mental arithmetic) were assessed during modulation of central SNS tone by intravenous infusions of dexmedetomidine (alpha2-agonist), yohimbine (alpha2-antagonist), and placebo. Cognitive performance was negatively affected by alpha2-agonism in all task conditions. By contrast, administration of yohimbine improved simple RT, while diminishing complex RT, supporting the assumption of a nonlinear way of action depending on task characteristics. Our results highlight the consequences of central (noradrenergic) SNS activation for cognitive-motor performance in RT tasks of varying complexity.


Assuntos
Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
Nat Commun ; 11(1): 3564, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678102

RESUMO

How does the brain control an effector as complex and versatile as the hand? One possibility is that neural control is simplified by limiting the space of hand movements. Indeed, hand kinematics can be largely described within 8 to 10 dimensions. This oft replicated finding has been construed as evidence that hand postures are confined to this subspace. A prediction from this hypothesis is that dimensions outside of this subspace reflect noise. To address this question, we track the hand of human participants as they perform two tasks-grasping and signing in American Sign Language. We apply multiple dimension reduction techniques and replicate the finding that most postural variance falls within a reduced subspace. However, we show that dimensions outside of this subspace are highly structured and task dependent, suggesting they too are under volitional control. We propose that hand control occupies a higher dimensional space than previously considered.


Assuntos
Mãos/fisiologia , Atividade Motora/fisiologia , Adulto , Fenômenos Biomecânicos , Humanos , Postura/fisiologia , Análise de Componente Principal , Desempenho Psicomotor/fisiologia , Volição/fisiologia , Adulto Jovem
10.
Soins Psychiatr ; 41(326): 30-34, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32718524

RESUMO

Addictive disorders restrict addicts' physical activity. On a neurobiological level, the reward system is disrupted. Pleasure is transformed into a constraint and patients lose control of themselves. Differing from a physical activity technique, psychomotor therapy, by drawing on the body's experience, in relation to the environment, can form part of the care plan. It is based on sensation, tonus, posture and tonico-emotional engagement.


Assuntos
Comportamento Aditivo/terapia , Terapias Mente-Corpo/métodos , Comportamento Aditivo/psicologia , Humanos , Desempenho Psicomotor
11.
Motor Control ; 24(3): 365-382, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663389

RESUMO

The authors examined how the stability of the current total isometric force (FT) produced by four fingers is influenced by previous and expected voluntary changes in FT. The authors employed the synergy index obtained from the across-trial uncontrolled manifold analysis to quantify the stability of FT. The authors compared two tasks with similar histories of FT changes; one in which participants expected changes in FT in the future, and one in which they expected no changes in FT. The stability of FT was lower in the former task, indicating the existence of a novel type of anticipatory synergy adjustment. Disparate histories of FT changes yield inconsistent changes in stability, driven by individual differences in the covariation in the finger forces that leave FT invariant. Future research should focus on exploring these individual differences to better understand how previous and expected behavior changes influence the stability of the current motor behavior.


Assuntos
Dedos/fisiologia , Força da Mão/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
12.
PLoS One ; 15(6): e0235083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579618

RESUMO

Cognitive flexibility is the ability to switch between different concepts or to adapt goal-directed behavior in a changing environment. Although, cognitive research on this ability has long been focused on the individual mind, it is becoming increasingly clear that cognitive flexibility plays a central role in our social life. This is particularly evident in turn-taking in verbal conversation, where cognitive flexibility of the individual becomes part of social flexibility in the dyadic interaction. In this work, we introduce a model that reveals different parameters that explain how people flexibly handle unexpected events in verbal conversation. In order to study hypotheses derived from the model, we use a novel experimental approach in which thirty pairs of participants engaged in a word-by-word interaction by taking turns in generating sentences word by word. Similar to well established individual cognitive tasks, participants needed to adapt their behavior in order to respond to their co-actor's last utterance. With our experimental approach we could manipulate the interaction between participants: Either both participants had to construct a sentence with a common target word (congruent condition) or with distinct target words (incongruent condition). We further studied the relation between the interactive Word-by-Word task measures and classical individual-centered, cognitive tasks, namely the Number-Letter task, the Stop-Signal task, and the GoNogo task. In the Word-by-Word task, we found that participants had faster response times in congruent compared to incongruent trials, which replicates the primary findings of standard cognitive tasks measuring cognitive flexibility. Further, we found a significant correlation between the performance in the Word-by-Word task and the Stop-Signal task indicating that participants with a high cognitive flexibility in the Word-by-Word task also showed high inhibition control.


Assuntos
Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Inteligibilidade da Fala/fisiologia , Adulto , Comunicação , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Percepção da Fala/fisiologia , Adulto Jovem
13.
PLoS One ; 15(6): e0234321, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502189

RESUMO

The sense of agency (SoA) refers to the perception that an action is the consequence of one's own intention. Studies exploring the SoA with neuroimaging techniques summarized the available data and confirmed a role of fronto-parietal areas and subcortical structures. However, these studies focused on specific regions of interest. We thus conducted a whole-brain meta-analysis to verify which regions emerge as significant for the SoA, specifically during motor execution. We performed a systematic search on PubMed, PsycINFO and Cochrane databases with the following inclusion criteria: studies investigating SoA with a visuo-motor task by means of neuroimaging in healthy subjects. We performed a quantitative, whole-brain, meta-analysis of neural correlates of the SoA based on the activation likelihood estimation. Of the 785 articles identified by our search, 22 studies met our inclusion criteria (169 foci, 295 subjects for decreased agency, and 58 foci, 165 subjects for normal agency). Neural correlates of decreased agency were the bilateral temporo-parietal junction (MNI: 50,-54,14; -44,-52,42; -48,-56,8). Normal agency showed no significant clusters of activation. This meta-analysis confirmed the key role of areas responsible for decreased SoA during motor control, whereas normal agency did not show a specific neural signature. This study sets the ground for future regions-of-interest analyses of neural correlates of SoA, as well as potential neuromodulation studies, which might be relevant in medical conditions presenting with abnormal SoA.


Assuntos
Encéfalo/diagnóstico por imagem , Atividade Motora/fisiologia , Autoimagem , Adolescente , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Intenção , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Desempenho Psicomotor/fisiologia , Autocontrole/psicologia , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/patologia
14.
PLoS One ; 15(6): e0234976, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579579

RESUMO

Previous studies have reported movement abnormalities in persons with schizophrenia. This study aimed to examine the differences between persons with chronic schizophrenia and healthy control participants in reaching movement and the effects of sensory signals on reaching performance in persons with chronic schizophrenia. A counter-balanced repeated-measures design was employed. Twenty persons with schizophrenia and 20 age- and gender-matched control participants were recruited in this study. Reaching performance was measured in three types of sensory signal conditions (visual, auditory, and no signal), i.e., two externally triggered and one self-initiated movement were assessed in reaction time/inter-response interval, movement time, peak velocity, percentage of time in which peak velocity occurred, and movement units. The results revealed significant main effects of group in reaction time/inter-response interval (p = 0.003), movement time (p < 0.001), peak velocity (p < 0.001), and movement units (p < 0.001). The persons with chronic schizophrenia demonstrated slower response to signals and in self-initiated movement, increased movement time, and less forceful and less smooth movement compared to healthy control participants when performing the reaching task. The interaction effect between group and signal in reaction time/inter-response interval was also significant (p < 0.001). The inter-response interval for self-initiated reaching was the shortest in healthy controls. Conversely, the inter-response interval for self-initiated reaching was the longest in persons with schizophrenia. The main effect of the signal on movement time was significant (p < 0.001). The movement time of reaching was longer in response to the auditory signal than in response to visual or self-initiated. The differences in percentages of time in which peak velocity occurred between persons with schizophrenia and healthy controls (p > 0.01) and across the three conditions (p > 0.01) were non-significant. Neither duration of illness nor antipsychotic dosage was significantly associated with reaching performance (all p > 0.01). In conclusion, these findings indicate that reaching movement in persons with chronic schizophrenia is slower, less forceful, and less coordinated compared to healthy control participants. In addition, persons with chronic schizophrenia also had shorter inter-response interval for self-initiated movement and shorter movement time in auditory signal condition, independent of duration of illness and antipsychotic dosage.


Assuntos
Desempenho Psicomotor/fisiologia , Esquizofrenia/fisiopatologia , Sensação/fisiologia , Adulto , Antipsicóticos/uso terapêutico , Estudos de Casos e Controles , Doença Crônica , Feminino , Humanos , Masculino , Esquizofrenia/tratamento farmacológico , Análise e Desempenho de Tarefas
15.
N Engl J Med ; 382(26): 2514-2523, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32579812

RESUMO

BACKGROUND: The effects on patient safety of eliminating extended-duration work shifts for resident physicians remain controversial. METHODS: We conducted a multicenter, cluster-randomized, crossover trial comparing two schedules for pediatric resident physicians during their intensive care unit (ICU) rotations: extended-duration work schedules that included shifts of 24 hours or more (control schedules) and schedules that eliminated extended shifts and cycled resident physicians through day and night shifts of 16 hours or less (intervention schedules). The primary outcome was serious medical errors made by resident physicians, assessed by intensive surveillance, including direct observation and chart review. RESULTS: The characteristics of ICU patients during the two work schedules were similar, but resident physician workload, described as the mean (±SD) number of ICU patients per resident physician, was higher during the intervention schedules than during the control schedules (8.8±2.8 vs. 6.7±2.2). Resident physicians made more serious errors during the intervention schedules than during the control schedules (97.1 vs. 79.0 per 1000 patient-days; relative risk, 1.53; 95% confidence interval [CI], 1.37 to 1.72; P<0.001). The number of serious errors unitwide were likewise higher during the intervention schedules (181.3 vs. 131.5 per 1000 patient-days; relative risk, 1.56; 95% CI, 1.43 to 1.71). There was wide variability among sites, however; errors were lower during intervention schedules than during control schedules at one site, rates were similar during the two schedules at two sites, and rates were higher during intervention schedules than during control schedules at three sites. In a secondary analysis that was adjusted for the number of patients per resident physician as a potential confounder, intervention schedules were no longer associated with an increase in errors. CONCLUSIONS: Contrary to our hypothesis, resident physicians who were randomly assigned to schedules that eliminated extended shifts made more serious errors than resident physicians assigned to schedules with extended shifts, although the effect varied by site. The number of ICU patients cared for by each resident physician was higher during schedules that eliminated extended shifts. (Funded by the National Heart, Lung, and Blood Institute; ROSTERS ClinicalTrials.gov number, NCT02134847.).


Assuntos
Unidades de Terapia Intensiva Pediátrica/organização & administração , Internato e Residência/organização & administração , Erros Médicos/estatística & dados numéricos , Segurança do Paciente , Admissão e Escalonamento de Pessoal , Tolerância ao Trabalho Programado , Carga de Trabalho , Estudos Cross-Over , Humanos , Erros Médicos/prevenção & controle , Desempenho Psicomotor/fisiologia , Sono , Fatores de Tempo
16.
Nat Commun ; 11(1): 3002, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532982

RESUMO

Humans observe a wide range of actions in their surroundings. How is the visual cortex organized to process this diverse input? Using functional neuroimaging, we measured brain responses while participants viewed short videos of everyday actions, then probed the structure in these responses using voxel-wise encoding modeling. Responses are well fit by feature spaces that capture the body parts involved in an action and the action's targets (i.e. whether the action was directed at an object, another person, the actor, and space). Clustering analyses reveal five large-scale networks that summarize the voxel tuning: one related to social aspects of an action, and four related to the scale of the interaction envelope, ranging from fine-scale manipulations directed at objects, to large-scale whole-body movements directed at distant locations. We propose that these networks reveal the major representational joints in how actions are processed by visual regions of the brain.


Assuntos
Encéfalo/fisiologia , Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Visual/fisiologia , Adulto , Fenômenos Biomecânicos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Neuroimagem Funcional/métodos , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Estimulação Luminosa/métodos , Comportamento Social , Córtex Visual/diagnóstico por imagem , Adulto Jovem
17.
PLoS One ; 15(6): e0234397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584827

RESUMO

When we perform an action, the outcome that follows it can change the value we place on that behaviour, making it more or less likely to be repeated in the future. However, the values that we learn are not objective: we interpret the outcomes that we receive for ourselves relative to those that share our environment, i.e. we engage in social comparison. The temporal dynamics of physiological responses to stimulus valuation in social learning tasks are poorly understood, particularly in human participants. Therefore, we recorded stimulus-locked event-related potentials with 64-channel EEG to examine stimulus valuation, following the design of a study previously used in macaques. Pairs of participants performed a social learning task in which they received outcomes sequentially for a presented stimulus (partner first) by pressing a button in response to a cue. There were two conditions: one in which stimulus values varied for the participant but output a constant rate of reward for the partner (self-variable blocks), and another condition in which this payout was reversed (other-variable blocks). We then measured participants' self-reported competitiveness. Approximately 200 ms post-stimulus, an ERP related to stimulus evaluation and attentional processing appeared to encode own stimulus value in self-variable blocks. In other-variable blocks the same pattern of activity was reversed, even though the value of the stimulus for the participant did not depend on the stimulus presented. Outcome-locked analyses further showed that attention dedicated to the partner's outcome was greater in more competitive participants. We conclude that subjective stimulus value can be reflected in early stimulus-locked ERP responses and that competitive participants may be more invested in their own performance relative to the other player, hence their increased interest in the outcome of their partner.


Assuntos
Aprendizado Social/fisiologia , Adulto , Atenção/fisiologia , Comportamento Competitivo/fisiologia , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Recompensa
18.
Nat Commun ; 11(1): 2757, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488065

RESUMO

In standard models of perceptual decision-making, noisy sensory evidence is considered to be the primary source of choice errors and the accumulation of evidence needed to overcome this noise gives rise to speed-accuracy tradeoffs. Here, we investigated how the history of recent choices and their outcomes interact with these processes using a combination of theory and experiment. We found that the speed and accuracy of performance of rats on olfactory decision tasks could be best explained by a Bayesian model that combines reinforcement-based learning with accumulation of uncertain sensory evidence. This model predicted the specific pattern of trial history effects that were found in the data. The results suggest that learning is a critical factor contributing to speed-accuracy tradeoffs in decision-making, and that task history effects are not simply biases but rather the signatures of an optimal learning strategy.


Assuntos
Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Animais , Teorema de Bayes , Comportamento Animal/fisiologia , Biologia Computacional , Modelos Teóricos , Desempenho Psicomotor/fisiologia , Ratos , Tempo de Reação , Reforço Psicológico , Incerteza
19.
PLoS One ; 15(6): e0224186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497045

RESUMO

Recent discussions in the literature, along with the revision of the Diagnostic and Statistical Manual (DSM) (American Psychiatric Association 2013), suggest aetiological commonalities between the highly comorbid Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD). Addressing this discussion requires studying these disorders together by comparing constructs typical to each of them. In the present study, we investigate global processing, known to be difficult for participants with ASD, and Intra-Subject Variability (ISV), known to be consistently increased in participants with ADHD, in groups, aged 10-13 years, with ADHD (n = 25), ASD without comorbid ADHD (ASD-) (n = 13) and ASD with ADHD (ASD+) (n = 18) in comparison with a typically developing group (n = 22). A Copying task, typically requiring global processing and in this case particularly designed using equally complex stimuli to also measure ISV across trials, was selected. Oculomotor measures in this task proved to be particularly sensitive to group differences. While increased ISV was not observed in the present task in participants with ADHD, both ASD groups looked longer on the figure to be drawn, indicating that global processing takes longer in ASD. However, the ASD+ group fixated on the figure only between drawing movements, whereas the ASD- group did this throughout the drawing process. The present study provides evidence towards ASD and ADHD being separate, not-overlapping, disorders. Since the pure ASD- group was affected more by central coherence problems than the ASD+ group, it may suggest that neuropsychological constructs interact differently in different clinical groups and sub-groups.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Espectro Autista/fisiopatologia , Movimento , Desempenho Psicomotor , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Espectro Autista/diagnóstico , Criança , Feminino , Humanos , Masculino
20.
PLoS One ; 15(5): e0232409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32357158

RESUMO

Though digital images and real objects are represented differently at a neural level and can evoke different behaviours, little work has directly compared the magnitude of social effects on real and digitally represented stimuli. Object-directed reaches are modified in the near space of others, while image-directed reaches are not, but the exact role of the presence versus location of the other person is unknown (Dosso and Kingstone, 2018). The present work probed the unique contribution of social presence (a passive observer) in shaping object- and image-directed reaching behaviour. In a shape-matching game, movements were performed more slowly and less efficiently when participants were observed by the experimenter, regardless of whether participants handled real objects or digital images. Our finding that social presence affects real- and image-directed reaches similarly supports the continued use of computer-generated objects to approximate human behaviour towards real objects when social effects on object-directed actions are studied.


Assuntos
Desempenho Psicomotor , Comportamento Social , Adolescente , Adulto , Simulação por Computador , Feminino , Humanos , Relações Interpessoais , Masculino , Modelos Psicológicos , Estimulação Luminosa , Análise e Desempenho de Tarefas , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA