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1.
Nat Commun ; 11(1): 4366, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868764

RESUMO

Armed forces often rely on strict hierarchical organization, where people are required to follow orders. In two cross-sectional studies, we investigate whether or not working in a military context influences the sense of agency and outcome processing, and how different durations (junior cadets vs senior cadets) and types (cadets vs privates) of military experience may modulate these effects. Participants could administer painful electrical shocks to a 'victim' in exchange for money, either by their own free choice, or following orders of the experimenter. Results indicate that working in a strictly hierarchical structure may have a generalized negative impact on one's own sense of agency and outcome processing by reducing it, even when participants could freely decide their action. However, trained officers showed an enhanced sense of agency and outcome processing. This study offers insights on the potential for training the sense of agency and outcome processing.


Assuntos
Militares/psicologia , Estudos Transversais , Humanos , Masculino , Psicologia Militar , Desempenho Psicomotor/fisiologia , Adulto Jovem
2.
PLoS One ; 15(8): e0238221, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866181

RESUMO

After perceiving cognitive conflicts or errors, children as well as adults adjust their performance in terms of reaction time slowing on subsequent actions, resulting in the so called post-conflict slowing and post-error slowing, respectively. The development of these phenomena has been studied separately and with different methods yielding inconsistent findings. We aimed to assess the temporal dynamics of these two slowing phenomena within a single behavioral task. To do so, 9-13-year-old children and young adults performed a Simon task in which every fifth trial was incongruent and thus induced cognitive conflict and, frequently, also errors. We compared the reaction times on four trials following a conflict or an error. Both age groups slowed down after conflicts and did so even more strongly after errors. Disproportionally high reaction times on the first post-error trial were followed by a steady flattening of the slowing. Generally, children slowed down more than adults. In addition to highlighting the phenomenal and developmental robustness of post-conflict and post-error slowing these findings strongly suggest increasingly efficient performance adjustment through fine-tuning of cognitive control in the course of development.


Assuntos
Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Adaptação Psicológica/fisiologia , Adolescente , Adulto , Criança , Conflito Psicológico , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
3.
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
4.
PLoS One ; 15(8): e0236809, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785237

RESUMO

While we are performing a demanding cognitive task, not only do we have a sense of cognitive effort, we are also subjectively aware that we are initiating, executing and controlling our thoughts and actions (i.e., sense of agency). Previous studies have shown that cognitive effort can be both detrimental and facilitative for the experienced sense of agency. We hypothesized that the reason for these contradictory findings might lie in the use of differential time windows in which cognitive effort operates. The current study therefore examined the effect of cognitive effort exerted on the current trial, on the previous trial or across a block of trials on sense of agency, using implicit (Experiment 1) and explicit (Experiment 2) measures of sense of agency. We showed that the exertion of more cognitive control on current trials led to a higher explicit sense of agency. This surprising result was contrasted to previous studies to establish potential reasons for this surprising finding and to formulate recommendations for future studies.


Assuntos
Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
5.
PLoS One ; 15(8): e0237807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817713

RESUMO

BACKGROUND: The Beery-Buktenica Test of Visual-Motor Integration (Beery VMI) is a commonly used standardized test of visual-motor integration. Performance on the test is related to academic achievement, but the effect of reduced visual acuity on test results is unknown. This study determined the visual acuity demand and the spacing of the test forms for the Beery VMI and its supplemental tests and investigated the effect of induced optical blur on test results in both adults and children. METHODS: The overall size and critical detail size of each form and the distance between the center of each form and its adjacent crowding source were measured. The visual acuity demand and angular separation of forms were calculated. Two groups of participants (adults aged ≥18 years [n = 19] and children aged 7-12 years [n = 20]) completed four sessions in which they performed the Beery VMI and the supplemental tests under different blur conditions (habitual near correction, monocular spherical blur, binocular spherical blur and binocular astigmatic blur) in a randomized order. RESULTS: Stroke width, overall form size and box size remained constant throughout the Beery VMI, whereas these reduced with increasing difficulty for the supplemental tests. Reduced near visual acuity from simulated blur resulted in reduced mean scores for the Beery VMI and its supplemental tests, compared with habitual near vision in both adults and children. Binocular spherical blur had the most detrimental effect (p<0.001), followed by binocular astigmatic blur (p<0.001) then monocular spherical blur (p = 0.022). CONCLUSIONS: In individuals with uncorrected spherical or astigmatic ametropia, reduced scores on the Beery VMI and its supplemental tests may be due to impaired near visual acuity and not reflect reduced visual-motor abilities. This highlights the importance of excluding reduced near visual acuity as a cause of reduced performance before diagnosing impairment and initiating treatment strategies for visual-motor integration.


Assuntos
Desenvolvimento Infantil/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adulto , Criança , Feminino , Humanos , Masculino , Erros de Refração/diagnóstico , Erros de Refração/fisiopatologia , Acuidade Visual/fisiologia , Adulto Jovem
6.
Psychol Aging ; 35(5): 720-728, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32744853

RESUMO

Inhibitory control is thought to be critical for appropriate response selection in an ever-changing environment and to decline with age. However, experimental paradigms (e.g., go/no-go) confound stimulus frequency with demands to respond or inhibit responding. The present study eliminated that confound by using a modified go/no-go task controlling for stimulus frequency differences (using frequent-go, infrequent-go, and infrequent no-go types of stimuli) in healthy older and young adults. Event-related potential (ERP) components related to detection of response conflict (N2) and response evaluation (P3) were also examined. Behaviorally, older and young adults were sensitive to stimulus frequencies indicated by significant slowing for the infrequent-go compared with the frequent-go stimuli observed in both groups. Furthermore, older adults were characterized by reduced commission errors and overall slowing, suggesting that they could take advantage of their slower performance. Increase of N2 amplitude was evident for correctly inhibited no-go stimuli in both groups. In contrast, no-go stimulus-related increase in P3 amplitude could be observed only in the young. Stimulus frequency-related ERP amplitude differences were not significant either in the young or in the older adults. These results suggest preserved behavioral control over inappropriate responses in older adults and indicate that efficient response inhibition is related to compensatory mechanisms. The age-related decrease in the P3 amplitude suggests that the evaluation of response inhibition (a) could be independent of the detection of response conflict and (b) supports the notion of strategic differences in performance with age. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Potenciais Evocados/fisiologia , Envelhecimento Saudável/genética , Desempenho Psicomotor/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
PLoS One ; 15(7): e0236416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735572

RESUMO

Proprioception acquires a crucial role in estimating the configuration of our body segments in space when visual information is not available. Proprioceptive accuracy is assessed by asking participants to match the perceived position of an unseen body landmark through reaching movements. This task was also adopted to study the perceived hand structure by computing the relative distances between averaged proprioceptive judgments (hand Localization Task). However, the pattern of proprioceptive errors leading to the misperceived hand structure is unexplored. Here, we aimed to characterize this pattern across different hand landmarks, having different anatomo-physiological properties and cortical representations. Furthermore, we sought to describe the error consistency and its stability over time. To this purpose, we analyzed the proprioceptive errors of 43 healthy participants during the hand Localization Task. We found larger but more consistent errors for the fingertips compared to the knuckles, possibly due to poorer proprioceptive signal, compensated by other sources of spatial information. Furthermore, we found a shift (overlap effect) and a temporal drift of the hand perceived position towards the shoulder of origin, which was consistent within and between subjects. The overlap effect had a greater influence on lateral compared to medial landmarks, leading to the hand width overestimation. Our results are compatible with domain-general and body-specific spatial biases affecting the proprioceptive localization of the hand landmarks, thus the apparent hand structure misperception.


Assuntos
Mãos/fisiologia , Movimento/fisiologia , Propriocepção/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Dedos/fisiologia , Corpo Humano , Humanos , Julgamento , Aprendizagem/fisiologia , Masculino , Polegar/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
8.
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
9.
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
10.
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
11.
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
12.
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
13.
PLoS One ; 15(7): e0235964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697771

RESUMO

Simon tasks reveal implicit processing conflicts that arise when the abstract coding of stimulus position is incongruent with coding for location of the output response. Participants were tested with two versions of a Simon task in a counterbalanced order to examine a potential female bias for attending to object characteristics versus object location. Both tasks used a triangle pointing to the left or right. A simple version presented the triangle in an inner or outer position relative to central fixation. A more complex version included a frame surrounding the inner-outer triangle presentation area in order to introduce additional visual elements for left/right visual processing. When the No Frame version was the first presented, there were no sex differences in the Simon effect in either version, which is consistent with results from other studies that did not provide feedback regarding accuracy. When the initial test was the Frame version, we observed a reverse Simon effect for incongruent triangles presented in the left inner position, with females faster than males to identify the incongruent condition versus the congruent (-59 vs -5 msec). In the No Frame condition that followed, females showed a carryover effect from the previous Frame condition, exhibiting positive Simon effects that were two fold larger than males for identifying incongruent stimuli presented in the left and right outer positions. Similar to previous Simon studies, females showed longer overall reaction times than males (~15%). The difference was not related to the Simon effect and is also found in other types of tasks involving early visual processing of objects with location. Based on sex differences in the Simon effect that emerged following initial experience of the triangle adjoining the frame, the present results support a female bias toward broader integration of objects within the context of location.


Assuntos
Comportamento de Escolha/fisiologia , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores Sexuais , Adulto Jovem
14.
Psychol Aging ; 35(6): 850-865, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32718157

RESUMO

We investigated aging effects in a task-switch paradigm with degraded stimuli administered to college students, 61-74 year olds, and 75-89 year olds. We studied switch costs (the performance difference between task-repeat and task-switch trials) in terms of accuracy and mean reaction times (RTs). Previous aging research focused on switch costs in terms of mean RTs (with accuracy at ceiling). Our results emphasize the importance of distinguishing between switch costs indexed by accuracy and by RTs because these measures lead to different interpretations. We used the Diffusion Decision Model (DDM; Ratcliff, 1978) to study the cognitive components contributing to switch costs. The DDM decomposed the cognitive process of task switching into multiple components. Two parameters of the model, the quality of evidence on which decisions were based (drift rate) and the duration of processes outside the decision process (nondecision time component), indexed different sources of switch costs. We found that older participants had larger switch costs indexed by nondecision time component than younger participants. This result suggests age-related deficits in preparatory cognitive processes. We also found group differences in switch costs indexed by drift rate for switch trials with high stimulus interference (stimuli with features relevant for both tasks). This result suggests that older participants have less effective cognitive processes involved in resolving interference. Our findings show that age-related effects in separate components of switch costs can be studied with the DDM. Our results demonstrate the utility of using discrimination tasks with degraded stimuli in conjunction with model-based analyses. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Envelhecimento/fisiologia , Tomada de Decisões , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudantes
15.
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
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.
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
18.
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
20.
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
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