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1.
Nat Commun ; 12(1): 4145, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230474

RESUMO

Organisms have the capacity to make decisions based solely on internal drives. However, it is unclear how neural circuits form decisions in the absence of sensory stimuli. Here we provide a comprehensive map of the activity patterns underlying the generation of saccades made in the absence of visual stimuli. We perform calcium imaging in the larval zebrafish to discover a range of responses surrounding spontaneous saccades, from cells that display tonic discharge only during fixations to neurons whose activity rises in advance of saccades by multiple seconds. When we lesion cells in these populations we find that ablation of neurons with pre-saccadic rise delays saccade initiation. We analyze spontaneous saccade initiation using a ramp-to-threshold model and are able to predict the times of upcoming saccades using pre-saccadic activity. These findings suggest that ramping of neuronal activity to a bound is a critical component of self-initiated saccadic movements.


Assuntos
Controle da População , Rombencéfalo/patologia , Rombencéfalo/fisiologia , Movimentos Sacádicos/fisiologia , Animais , Potenciais Evocados Visuais , Movimentos Oculares , Tecnologia de Rastreamento Ocular/psicologia , Larva , Neurônios/patologia , Neurônios/fisiologia , Tempo de Reação/fisiologia , Peixe-Zebra
2.
Nat Commun ; 12(1): 4448, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290247

RESUMO

Cortical representations of brief, static stimuli become more invariant to identity-preserving transformations along the ventral stream. Likewise, increased invariance along the visual hierarchy should imply greater temporal persistence of temporally structured dynamic stimuli, possibly complemented by temporal broadening of neuronal receptive fields. However, such stimuli could engage adaptive and predictive processes, whose impact on neural coding dynamics is unknown. By probing the rat analog of the ventral stream with movies, we uncovered a hierarchy of temporal scales, with deeper areas encoding visual information more persistently. Furthermore, the impact of intrinsic dynamics on the stability of stimulus representations grew gradually along the hierarchy. A database of recordings from mouse showed similar trends, additionally revealing dependencies on the behavioral state. Overall, these findings show that visual representations become progressively more stable along rodent visual processing hierarchies, with an important contribution provided by intrinsic processing.


Assuntos
Tempo de Reação/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Animais , Locomoção/fisiologia , Camundongos , Modelos Neurológicos , Neurônios/fisiologia , Estimulação Luminosa , Ratos , Vias Visuais/fisiologia , Vigília/fisiologia
3.
Medicine (Baltimore) ; 100(25): e26464, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34160450

RESUMO

ABSTRACT: Previous studies have identified inhibitory deficits in dyslexic children, but we have little understanding of their neural mechanisms, especially for Chinese children with developmental dyslexia.We used a double-blind controlled trial to study the electroencephalogram responses of dyslexic and non-dyslexic children when performing the Stroop color-word test.Behavioral data showed differences in response time and accuracy between the 2 groups. In the event-related potentials (ERP) results, dyslexic children displayed larger P2 and P3b on congruent trials, while non-dyslexic children displayed larger P2 and P3b on incongruent trials, the 2 groups showed opposite brain activation patterns on the Stroop test.Dyslexic children have poor inhibitory function, and this poor inhibition may be related to their abnormal brain activation patterns.


Assuntos
Encéfalo/fisiopatologia , Dislexia/fisiopatologia , Potenciais Evocados/fisiologia , Inibição Neural/fisiologia , Teste de Stroop , Estudos de Casos e Controles , Criança , Método Duplo-Cego , Dislexia/diagnóstico , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia
4.
J Clin Neurosci ; 89: 139-143, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119257

RESUMO

Functional movement disorder (FMD) presents as disabling motor symptoms that cannot be explained by organic processes. Despite the lack of lesion or known central nervous system dysfunction, distortion in sensorimotor processing in movement generation and execution is often observed. A person's capacity to judge laterality of a body part requires processing of sensorimotor information. This prospective observational study compared reaction time (RT) and accuracy (ACC) of hand laterality recognition between 30 people diagnosed with FMD and 30 age-matched healthy control participants. The association of RT and ACC with severity of FMD as measured by the Simplified Functional Movement Disorders Rating Scale (SFMDRS) was also explored. RT was on average 0.6 s slower (95% CI 0.4 - 0.8 s, p < 0.001) in patients with FMD (mean 2.2 s, standard deviation (SD) 0.5) than controls (mean 1.7 s, SD 0.3). ACC was on average 8.9% lower (95% CI -15.7 - -2.2, p = 0.01) in patients with FMD (mean 79.6%, SD 16.6) than controls (mean 88.5%, SD 8.1). When adjusted for SFMDRS using robust regression, RT was 0.3 s slower (95% CI 0.01 - 0.5, p = 0.04) in cases than in controls, but ACC was no longer different between groups. There was a moderate negative correlation between RT and ACC in FMD patients (ρ -0.58, p < 0.001 but not in controls (ρ -0.26, p = 0.17). People with FMD had significantly slower RT and lower ACC compared to the control group. These results provide new insights into underlying sensorimotor processing deficits in those with FMD.


Assuntos
Lateralidade Funcional/fisiologia , Mãos/fisiologia , Imaginação/fisiologia , Transtornos dos Movimentos/fisiopatologia , Movimento/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/diagnóstico , Transtornos dos Movimentos/psicologia , Estudos Prospectivos , Tempo de Reação/fisiologia
5.
Neuron ; 109(14): 2353-2361.e11, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34171289

RESUMO

To navigate social environments, people must simultaneously hold representations about their own and others' abilities. During self-other mergence, people estimate others' abilities not only on the basis of the others' past performance, but the estimates are also influenced by their own performance. For example, if we perform well, we overestimate the abilities of those with whom we are co-operating and underestimate competitors. Self-other mergence is associated with specific activity patterns in the dorsomedial prefrontal cortex (dmPFC). Using a combination of non-invasive brain stimulation, functional magnetic resonance imaging, and computational modeling, we show that dmPFC neurostimulation silences these neural signatures of self-other mergence in relation to estimation of others' abilities. In consequence, self-other mergence behavior increases, and our assessments of our own performance are projected increasingly onto other people. This suggests an inherent tendency to form interdependent social representations and a causal role of the dmPFC in separating self and other representations.


Assuntos
Modelos Neurológicos , Córtex Pré-Frontal/fisiologia , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Tempo de Reação/fisiologia , Comportamento Social , Estimulação Magnética Transcraniana , Adulto Jovem
6.
Knee ; 30: 214-240, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33945981

RESUMO

BACKGROUND: There is limited evidence available on return to driving for patients undergoing knee arthroplasty (KA). Primarily, surgeons have used brake reaction time as a surrogate measure of safe return to driving. The purpose of this study was to review existing literature and provide guidance on the recovery of braking performance following knee arthroplasty. METHODS: A literature search was performed for prospective studies on driving after KA. Two reviewers screened citations for inclusion, assessed methodological quality, and extracted data. Values for total brake reaction-time (TBRT), movement-time (MT), reaction-time (RT), and braking-force (BF) were included for meta-analysis. RESULTS: Twelve studies with 368 subjects were identified. TBRT, RT, MT, and BF relative to preoperative baseline were assessed. Meta-analysis of TBRT showed a significant improvement from preoperative baseline at 3 months & 1 year (p = 0.003 & p = 0.0001). MT showed a significant increase at 2 and 4 weeks (p = 0.00001 & p = 0.03) before returning to no being significantly different at 6 weeks and beyond. In contrast RTs were noted to improve significantly 2 weeks (p = 0.006), 4 weeks (p = 0.03), and 1 year (p = 0.0002). CONCLUSION: Meta-analysis showed no significant difference in TBRT up until 3 months. RT increased significantly post-operatively suggesting it is not a reliable indicator. MT in contrast was significantly decreased post KA and may represent a more reliable measure of braking performance post KA. Surgeons should consider these recommendations and other patient factors that determine fitness to drive prior to advising their patients on a safe to return to driving.


Assuntos
Artroplastia do Joelho , Condução de Veículo , Tempo de Reação/fisiologia , Artroplastia do Joelho/reabilitação , Humanos , Aptidão Física , Período Pós-Operatório , Estudos Prospectivos , Fatores de Tempo
7.
Traffic Inj Prev ; 22(5): 366-371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33960857

RESUMO

OBJECTIVE: Sleep deprivation is known to affect driving behavior and may lead to serious car accidents similar to the effects from e.g., alcohol. In a previous study, we have demonstrated that the use of machine learning techniques allows adequate characterization of abnormal driving behavior after alprazolam and/or alcohol intake. In the present study, we extend this approach to sleep deprivation and test the model for characterization of new interventions. We aimed to classify abnormal driving behavior after sleep deprivation, and, by using a machine learning model, we tested if this model could also pick up abnormal driving behavior resulting from other interventions. METHODS: Data were collected during a previous study, in which 24 subjects were tested after being sleep-deprived and after a well-rested night. Features were calculated from several driving parameters, such as the lateral position, speed of the car, and steering speed. In the present study, we used a gradient boosting model to classify sleep deprivation. The model was validated using a 5-fold cross validation technique. Next, probability scores were used to identify the overlap of driving behavior after sleep deprivation and driving behavior affected by other interventions. In the current study alprazolam, alcohol, and placebo are used to test/validate the approach. RESULTS: The sleep deprivation model detected abnormal driving behavior in the simulator with an accuracy of 77 ± 9%. Abnormal driving behavior after alprazolam, and to a lesser extent also after alcohol intake, showed remarkably similar characteristics to sleep deprivation. The average probability score for alprazolam and alcohol measurements was 0.79, for alcohol 0.63, and for placebo only 0.27 and 0.30, matching the expected relative drowsiness. CONCLUSION: We developed a model detecting abnormal driving induced by sleep deprivation. The model shows the similarities in driving characteristics between sleep deprivation and other interventions, i.e., alcohol and alprazolam. Consequently, our model for sleep deprivation may serve as a next reference point for a driving test battery of newly developed drugs.


Assuntos
Acidentes de Trânsito/prevenção & controle , Atenção/fisiologia , Tempo de Reação/fisiologia , Privação do Sono/fisiopatologia , Adulto , Alprazolam/uso terapêutico , Condução de Veículo , Simulação por Computador/estatística & dados numéricos , GABAérgicos/uso terapêutico , Humanos , Aprendizado de Máquina , Masculino , Vigília/fisiologia
8.
Nat Commun ; 12(1): 3177, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039970

RESUMO

Memories are thought to undergo an episodic-to-semantic transformation in the course of their consolidation. We here test if repeated recall induces a similar semanticisation, and if the resulting qualitative changes in memories can be measured using simple feature-specific reaction time probes. Participants studied associations between verbs and object images, and then repeatedly recalled the objects when cued with the verb, immediately and after a two-day delay. Reaction times during immediate recall demonstrate that conceptual features are accessed faster than perceptual features. Consistent with a semanticisation process, this perceptual-conceptual gap significantly increases across the delay. A significantly smaller perceptual-conceptual gap is found in the delayed recall data of a control group who repeatedly studied the verb-object pairings on the first day, instead of actively recalling them. Our findings suggest that wake recall and offline consolidation interact to transform memories over time, strengthening meaningful semantic information over perceptual detail.


Assuntos
Consolidação da Memória/fisiologia , Rememoração Mental/fisiologia , Tempo de Reação/fisiologia , Adolescente , Feminino , Voluntários Saudáveis , Humanos , Masculino , Memória Episódica , Memória de Curto Prazo , Semântica , Fatores de Tempo , Adulto Jovem
9.
PLoS One ; 16(4): e0234219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852575

RESUMO

Category-specific impairments witnessed in patients with semantic deficits have broadly dissociated into natural and artificial kinds. However, how the category of food (more specifically, fruits and vegetables) fits into this distinction has been difficult to interpret, given a pattern of deficit that has inconsistently mapped onto either kind, despite its intuitive membership to the natural domain. The present study explores the effects of a manipulation of a visual sensory (i.e., color) or functional (i.e., orientation) feature on the consequential semantic processing of fruits and vegetables (and tools, by comparison), first at the behavioral and then at the neural level. The categorization of natural (i.e., fruits/vegetables) and artificial (i.e., utensils) entities was investigated via cross-modal priming. Reaction time analysis indicated a reduction in priming for color-modified natural entities and orientation-modified artificial entities. Standard event-related potentials (ERP) analysis was performed, in addition to linear classification. For natural entities, a N400 effect at central channel sites was observed for the color-modified condition compared relative to normal and orientation conditions, with this difference confirmed by classification analysis. Conversely, there was no significant difference between conditions for the artificial category in either analysis. These findings provide strong evidence that color is an integral property to the categorization of fruits/vegetables, thus substantiating the claim that feature-based processing guides as a function of semantic category.


Assuntos
Cognição/fisiologia , Semântica , Percepção Visual/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Cor , Eletroencefalografia , Potenciais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Alimentos , Frutas , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
10.
Elife ; 102021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33830017

RESUMO

There are many monitoring environments, such as railway control, in which lapses of attention can have tragic consequences. Problematically, sustained monitoring for rare targets is difficult, with more misses and longer reaction times over time. What changes in the brain underpin these 'vigilance decrements'? We designed a multiple-object monitoring (MOM) paradigm to examine how the neural representation of information varied with target frequency and time performing the task. Behavioural performance decreased over time for the rare target (monitoring) condition, but not for a frequent target (active) condition. This was mirrored in neural decoding using magnetoencephalography: coding of critical information declined more during monitoring versus active conditions along the experiment. We developed new analyses that can predict behavioural errors from the neural data more than a second before they occurred. This facilitates pre-empting behavioural errors due to lapses in attention and provides new insight into the neural correlates of vigilance decrements.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Tempo de Reação/fisiologia , Vigília/fisiologia , Adulto , Feminino , Humanos , Masculino , New South Wales , Adulto Jovem
11.
Games Health J ; 10(2): 115-120, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33818136

RESUMO

Objective: Slowing information processing speed (IPS) is a biomarker of neuronal damage in patients with multiple sclerosis (pwMS). A focus on IPS might be the ideal solution in the perspective of promptly detecting cognitive changes over time. We developed a tablet-based home-made videogame to test the sensitivity of this device in measuring subclinical IPS in pwMS. Materials and Methods: Forty-three pwMS without cognitive impairment and 20 healthy controls (HCs) were administered the videogame task with a tablet. Response times (RTs) and accuracy were recorded. Results: PwMS (mean RTs = 505.5 ± 73.9 ms) were significantly slower than HCs (mean RTs = 462.3 ± 40.3 ms, P = 0.014) on the videogame task. A moderate but significant correlation (r = -0.35, P = 0.03) between mean RTs and the Symbol Digit Modalities Test was observed. Conclusion: Our videogame showed good sensitivity in measuring IPS in apparently cognitive normal pwMS. Computerized testing might be useful in screening initial cognitive dysfunction that should be monitored as a marker of underlying disease progression. IRB approval Number is 2332CESC.


Assuntos
Processamento Eletrônico de Dados/normas , Esclerose Múltipla/complicações , Jogos de Vídeo/normas , Adulto , Processamento Eletrônico de Dados/classificação , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Jogos de Vídeo/tendências
12.
Gait Posture ; 86: 346-353, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33857800

RESUMO

BACKGROUND: Motor learning has been investigated using various paradigms, including serial reaction time tasks (SRTT) that examine upper extremity reaching and pointing while seated. Few studies have used a stepping SRTT, which could offer additional insights into motor learning involving postural demands. For a task to measure motor learning, naïve participants must demonstrate a) improved performance with task practice, and b) a dose-response relationship to learning the task. RESEARCH QUESTION: Is a stepping SRTT feasible and efficacious for measuring motor learning? METHODS: In this prospective study, 20 participants stood on an instrumented mat and were presented with stimuli on a computer screen. They stepped to the corresponding positions on the mat as quickly as possible. Presented stimuli included random sequences and a blinded imbedded repeating sequence. Three days after completing the randomly assigned practice dose [high dose group (n = 10) performed 4320 steps; low dose group (n = 10) performed 144 steps], a retention test of 72 steps was performed. Feasibility was measured as the proportion of participants who completed the assigned practice dose without adverse events. Efficacy was measured as within-group performance improvement on the random sequences and on the repeating sequence (paired t-tests), as well as a dose-response relationship to learning both types of sequences (independent t-tests). RESULTS: All participants (mean age 26.8 years) completed all practice sessions without adverse events, indicating feasibility. High dose practice resulted in performance improvement while low dose did not; a dose-response relationship was found, with high dose practice resulting in greater learning of the task than low dose practice, indicating efficacy. SIGNIFICANCE: This stepping SRTT is a feasible and efficacious way to measure motor learning, which could provide critical insights into anticipatory stepping, postural control, and fall risk. Future research is needed to determine feasibility, efficacy, and optimal practice dosages for older and impaired populations.


Assuntos
Aprendizagem/fisiologia , Tempo de Reação/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
13.
Psychopharmacology (Berl) ; 238(8): 2167-2177, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33834255

RESUMO

RATIONALE: Noradrenaline (NE) is closely related to attentive performance and impulsive control. However, the potential sex differences regarding attention and impulsivity under the noradrenergic modulation have been largely neglected. Therefore, our study aimed to investigate whether male and female rats exhibit differential responses to NE-related drugs during the five-choice serial reaction time task (5CSRT). METHODS: Male and female rats were trained in 5CSRT and administered with different NE drugs after obtaining stable baseline performance: atipamezole, a highly selective α2 receptor antagonist; prazosin, an α1 receptor antagonist; and atomoxetine, a selective NE reuptake inhibitor. Later, prazosin was selected to co-administration with atomoxetine. RESULTS: Male and female rats exhibited equal learning speed, and no significant baseline differences were found as measured by the 5CSRT. Atomoxetine decreased premature responses in both sexes, but the extent of this reduction was different, with the reduction greater in males. Besides, atomoxetine (1.8 mg/kg) increased the error of omissions in females. The high dose of prazosin (0.5 mg/kg) decreased the accuracy only in male rats, but this was ameliorated by the co-administration with atomoxetine. CONCLUSIONS: Atomoxetine showed significant improvement in impulsivity, but atomoxetine had less beneficial effects on impulsive control in females than in males, and it even impaired attentional performance in female rats. The α1 receptors were mainly responsible for NE drug-related sex differences in attention rather than impulsivity. The results obtained in this study indicate that the sex differences exist in both attention and impulsivity by the modulation of noradrenaline and raise the concern to improve sex-specific treatments.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Atenção/efeitos dos fármacos , Atenção/fisiologia , Comportamento Impulsivo/efeitos dos fármacos , Comportamento Impulsivo/fisiologia , Caracteres Sexuais , Animais , Cloridrato de Atomoxetina/farmacologia , Feminino , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia
14.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807635

RESUMO

(1) Background: Atypical auditory perception has been reported in individuals with autism spectrum disorder (ASD). Altered auditory evoked brain responses are also associated with childhood ASD. They are likely to be associated with atypical brain maturation. (2) Methods: This study examined children aged 5-8 years old: 29 with ASD but no intellectual disability and 46 age-matched typically developed (TD) control participants. Using magnetoencephalography (MEG) data obtained while participants listened passively to sinusoidal pure tones, bilateral auditory cortical response (P1m) was examined. (3) Results: Significantly shorter P1m latency in the left hemisphere was found for children with ASD without intellectual disabilities than for children with TD. Significant correlation between P1m latency and language conceptual ability was found in children with ASD, but not in children with TD. (4) Conclusions: These findings demonstrated atypical brain maturation in the auditory processing area in children with ASD without intellectual disability. Findings also suggest that ASD has a common neural basis for pure-tone sound processing and language development. Development of brain networks involved in language concepts in early childhood ASD might differ from that in children with TD.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Deficiência Intelectual/fisiopatologia , Tempo de Reação/fisiologia , Córtex Auditivo/fisiopatologia , Criança , Pré-Escolar , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino
15.
Psychol Aging ; 36(2): 214-231, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33900104

RESUMO

Despite several meta-analyses suggesting that age differences in attentional control are "greatly exaggerated," there have been multiple reports of disproportionate age differences in the Stroop effect. The Stroop task is widely accepted as the gold standard for assessing attentional control and has been critical in comparisons across development and in studies of neuropsychological patient groups. However, accounting for group differences in processing speed is a notorious challenge in interpreting reaction time (RT) data. Within the aging literature, prior meta-analyses have relied on Brinley and State-Trace techniques to account for overall processing speed differences in evaluating the effects of within-participant manipulations. Such analyses are based on mean performance per group per study and have been criticized as potentially being insensitive to within-participant manipulations. In order to further examine possible age differences in Stroop performance, we amassed a dataset from 33 different computerized, color-naming Stroop task studies with available trial-level data from 2,896 participants. We conducted meta-regression analyses on a wide set of dependent measures that control for general slowing, tested for publication bias, and examined four potential methodological moderators. We also conducted linear mixed-effect modeling allowing the intercept to vary randomly for each participant, thereby accounting for individual differences in processing speed. All analyses, with the exception of the Brinley and State-Trace techniques, produced clear evidence supporting a disproportionate age difference in the Stroop effect above and beyond the effects of general slowing. Discussion highlights the importance of trial-level data in accounting for group differences in processing speed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Envelhecimento/psicologia , Cognição/fisiologia , Teste de Stroop , Adulto , Atenção/fisiologia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Análise de Regressão
16.
Scand J Med Sci Sports ; 31(8): 1699-1707, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33908068

RESUMO

Weaker hamstrings muscular forces and lower ratio of the hamstrings/quadriceps muscular forces in female athletes have been identified as modifiable risk factors for anterior cruciate ligament (ACL) injuries. However, sex differences in athletes' ability to react to visual cues (Choice Visual-Motor Reaction Time: VMRT) and to generate knee muscular forces (rate of force development: RFD) immediately following the visual cues were largely unknown. Therefore, the purpose of the study was to examine sex differences in Choice VMRT and RFD. A total of 50 high school basketball athletes (26F/24 M) participated in the study. Subjects sat in the knee dynamometer chair with their knee secured at 70° of knee flexion and performed knee extension or flexion maximum voluntary isometric contractions immediately after they saw the visual cue: "UP" or "DOWN" arrows, respectively. Choice VMRT was defined as the time between the visual cue and the initiation of muscular force development (>5Newtons). RFD was calculated by dividing the changes in forces over the changes in time at four time points (0-50/100/150/200 ms). Peak muscular forces and RFD were normalized to their body mass. Average of three trials in each direction (flexion and extension) in each leg was used for statistical analyses. Females had significantly slower Choice VMRT (p < 0.001-0.027) and lower knee extension RFD at 100 ms (p = 0.005). In addition, females had significantly higher knee flexion/extension ratio than males in late RFD (150 ms and 200 ms) (p < 0.004). The current study has provided additional sensorimotor characteristics of athletes and sexes in addition to their knee muscular characteristics.


Assuntos
Basquetebol/fisiologia , Músculos Isquiossurais/fisiologia , Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Músculo Quadríceps/fisiologia , Tempo de Reação/fisiologia , Adolescente , Feminino , Humanos , Contração Isométrica , Masculino , Fatores Sexuais
17.
J Neurosci ; 41(14): 3180-3191, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33653697

RESUMO

Past work has demonstrated that active suppression of salient distractors is a critical part of visual selection. Evidence for goal-driven suppression includes below-baseline visual encoding at the position of salient distractors (Gaspelin and Luck, 2018) and neural signals such as the distractor positivity (Pd) that track how many distractors are presented in a given hemifield (Feldmann-Wüstefeld and Vogel, 2019). One basic question regarding distractor suppression is whether it is inherently spatial or nonspatial in character. Indeed, past work has shown that distractors evoke both spatial (Theeuwes, 1992) and nonspatial forms of interference (Folk and Remington, 1998), motivating a direct examination of whether space is integral to goal-driven distractor suppression. Here, we use behavioral and EEG data from adult humans (male and female) to provide clear evidence for a spatial gradient of suppression surrounding salient singleton distractors. Replicating past work, both reaction time and neural indices of target selection improved monotonically as the distance between target and distractor increased. Importantly, these target selection effects were paralleled by a monotonic decline in the amplitude of the Pd, an electrophysiological index of distractor suppression. Moreover, multivariate analyses revealed spatially selective activity in the θ-band that tracked the position of the target and, critically, revealed suppressed activity at spatial channels centered on distractor positions. Thus, goal-driven selection of relevant over irrelevant information benefits from a spatial gradient of suppression surrounding salient distractors.SIGNIFICANCE STATEMENT Past work has shown that distractor suppression is an important part of goal-driven attentional selection, but has not yet revealed whether suppression is spatially directed. Using behavioral data, event-related potentials (ERPs) of the EEG signal [N2pc and distractor positivity (Pd) component], as well as a multivariate model of EEG data [channel tuning functions (CTF)], we show that suppression-related neural activity increases monotonically as the distance between targets and distractors decreases, and that spatially-selective activity in the θ-band reveals depressed activity in spatial channels that index distractor positions. Thus, we provide robust evidence for spatially-guided distractor suppression, a result that has important implications for models of goal-driven attentional control.


Assuntos
Atenção/fisiologia , Potenciais Evocados Visuais/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Percepção Visual/fisiologia , Adulto Jovem
18.
PLoS One ; 16(3): e0247254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33724991

RESUMO

Having an optimal quality of vision as well as adequate cognitive capacities is known to be essential for driving safety. However, the interaction between vision and cognitive mechanisms while driving remains unclear. We hypothesized that, in a context of high cognitive load, reduced visual acuity would have a negative impact on driving behavior, even when the acuity corresponds to the legal threshold for obtaining a driving license in Canada, and that the impact observed on driving performance would be greater with the increase in the threshold of degradation of visual acuity. In order to investigate this relationship, we examined driving behavior in a driving simulator under optimal and reduced vision conditions through two scenarios involving different levels of cognitive demand. These were: 1. a simple rural driving scenario with some pre-programmed events and 2. a highway driving scenario accompanied by a concurrent task involving the use of a navigation device. Two groups of visual quality degradation (lower/ higher) were evaluated according to their driving behavior. The results support the hypothesis: A dual task effect was indeed observed provoking less stable driving behavior, but in addition to this, by statistically controlling the impact of cognitive load, the effect of visual load emerged in this dual task context. These results support the idea that visual quality degradation impacts driving behavior when combined with a high mental workload driving environment while specifying that this impact is not present in the context of low cognitive load driving condition.


Assuntos
Condução de Veículo/psicologia , Direção Distraída/psicologia , Tempo de Reação/fisiologia , Adulto , Atenção/fisiologia , Canadá , Cognição/fisiologia , Simulação por Computador , Feminino , Humanos , Masculino , Desempenho Psicomotor , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Percepção Visual/fisiologia
19.
PLoS One ; 16(3): e0247565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661963

RESUMO

Identification of success factors in wrestling as well as establishing their hierarchy are crucial from a cognitive and practical standpoint. It may provide a lot of practical recommendations related to wrestling-specific training. The aim of this study was to identify and establish the hierarchy of success factors in wrestling regardless of a fighting style and weight class. This study included 168 elite male freestyle and Greco-Roman wrestlers. They were divided into two groups: athletes who won medals (successful wrestlers) in high-rank competitions (Polish Championships or higher) and those who did not win any medals (less successful wrestlers) in those competitions. The following elements were assessed: anthropological measurements, body composition, dynamic strength, strength endurance, agility, special endurance, wrestling-specific fitness, response time, technical wrestling skills and anaerobic capacity. For initial data analysis, one-way ANOVA (α = 0.005) was used. Random Forests classifier was employed to identify success factors and to determine the importance of each of these factors in terms of sports performance. Seven key success factors were identified: anaerobic power, strength endurance, response time, special endurance, wrestling-specific fitness and technical wrestling skills performed in a horizontal position. Random Forests turned out to be an effective method of modelling success in wrestling (compared to SVM and KNN, which were also used in the study). These findings suggest that wrestling-specific training can be effectively monitored by controlling several vital indicators of athletes' preparedness: anaerobic power, strength endurance, response time, special endurance, wrestling-specific fitness and technical wrestling skills (the performance of reverse waistlock from a standing position and trunk grip gut wrench assessed by experts).


Assuntos
Atletas/estatística & dados numéricos , Desempenho Atlético/fisiologia , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Músculo Esquelético/fisiologia , Luta Romana/fisiologia , Limiar Anaeróbio/fisiologia , Análise de Variância , Humanos , Masculino , Educação Física e Treinamento/métodos , Resistência Física/fisiologia , Aptidão Física/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
20.
J Sport Exerc Psychol ; 43(2): 155-170, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721839

RESUMO

The authors investigated relationships between emotions, coping, and resilience across two studies. In Study 1a, 319 athletes completed dispositional questionnaires relating to the aforementioned constructs. In Study 1b, 126 athletes from Study 1a repeated the same questionnaires 6 months later. In Study 2, 21 athletes were randomly allocated to an emotional (e.g., pleasant or unpleasant emotions) or control group and undertook a laboratory-based reaction-time task across three time points. Questionnaires and salivary cortisol samples were collected before and after each performance with imagery-based emotional manipulations engendered during the second testing session. Partial longitudinal evidence of the broaden-and-build effects of pleasant emotions was found. Pleasant emotions may undo lingering cognitive resource losses incurred from previous unpleasant emotional experiences. In Study 2, pleasant and unpleasant emotions had an immediate and sustained psychophysiological and performance impact. Taken together, this research supports the application of broaden-and-build theory in framing emotional interventions for athletes.


Assuntos
Atletas/psicologia , Desempenho Atlético/fisiologia , Emoções , Tempo de Reação/fisiologia , Resiliência Psicológica , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
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