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1.
Hum Mov Sci ; 95: 103222, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696913

RESUMO

The motor-cognitive model proposes that movement imagery additionally requires conscious monitoring owing to an absence of veridical online sensory feedback. Therefore, it is predicted that there would be a comparatively limited ability for individuals to update or correct movement imagery as they could within execution. To investigate, participants executed and imagined target-directed aiming movements featuring either an unexpected target perturbation (Exp. 1) or removal of visual sensory feedback (Exp. 2). The results of both experiments indicated that the time-course of executed and imagined movements was equally influenced by each of these online visual manipulations. Thus, contrary to some of the tenets of the motor-cognitive model, movement imagery holds the capacity to interpolate online corrections despite the absence of veridical sensory feedback. The further theoretical implications of these findings are discussed.


Assuntos
Retroalimentação Sensorial , Imaginação , Desempenho Psicomotor , Humanos , Adulto Jovem , Masculino , Feminino , Adulto , Cognição , Movimento , Orientação , Tempo de Reação
2.
Virchows Arch ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38637342

RESUMO

Somatic and biallelic DICER1 mutations are reported in subsets of thyroid tumors, supporting the role of this gene in thyroid tumor development. As recent studies have brought attention to macrofollicular patterns, atrophic changes, and papillary structures as being associated with DICER1 mutations, we sought to explore these observations in a bi-institutional cohort. A total of 61 thyroid lesions (54 tumors and 7 cases of thyroid follicular nodular disease; TFND), including 26 DICER1 mutated and 35 DICER1 wildtype controls were subjected to histological re-investigation and clinical follow-up. DICER1-mutated lesions showed a statistically significant association with younger age at surgery (29.2 ± 12.5 versus 51.3 ± 18.8, p = 0.0001), a predominant macrofollicular growth pattern (20/26 mutated cases versus 18/35 wildtype; p = 0.01) and atrophic changes (20/26 mutated cases versus 2/35 wildtype; p = 0.0001). Similar results were obtained when excluding TFND cases. We also present clinical and histological triaging criteria for DICER1 sequencing of thyroid lesions, which led to the identification of DICER1 variants in 16 out of 26 cases (62%) when followed. Among these, 3 out of 12 cases with available data were found to carry a constitutional DICER1 mutation. This observation suggests that the majority of DICER1 mutations are somatic-however implies that sequencing of constitutional tissues could be clinically motivated. We conclude that DICER1 mutations are amassed in younger patients with macrofollicular-patterned tumors and, most strikingly, atrophic changes. Given the rate of constitutional involvement, our findings could be of clinical value, allowing the pathologist to triage cases for genetic testing based on histological findings.

3.
Cancer Cytopathol ; 132(6): 359-369, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520219

RESUMO

BACKGROUND: DICER1 mutations, though infrequent, are encountered on preoperative molecular testing of indeterminate adult and pediatric thyroid fine-needle aspiration (FNA) specimens. Yet, published cytomorphologic features of DICER1-altered thyroid lesions are limited. Cytomorphological features of DICER1-altered thyroid lesions were examined in a multipractice FNA cohort with clinical, radiological, and histologic data. METHODS: The cohort comprised 18 DICER1-altered thyroid FNAs, with 14 having slides available and eight having corresponding surgical resections. Smears, ThinPrep, and formalin-fixed cell block slides were reviewed and correlated with histology, when available. Clinical and radiologic data were obtained from the medical record. RESULTS: Most DICER1-altered FNAs were classified as atypia of undetermined significance (94.4%). DICER1 mutations occurred in codons 1709 (50%), 1810 (27.8%), and 1813 (22.2%). One patient had an additional DICER1 p.D1822N variant in both of their FNAs. Lesions were often hypoechoic (35.3%) and solid (47.1%) on ultrasound. Notable cytomorphologic features include mixed but prominent microfollicular or crowded component, variable colloid, and insignificant nuclear atypia. On resection (n = 10), histologic diagnoses ranged from benign follicular adenoma and low-risk follicular thyroid carcinoma to high-grade follicular-derived nonanaplastic thyroid carcinoma. Subcapsular infarct-type change was the most common histologic change. There was no evidence of recurrence or metastasis in eight patients on limited follow-up. CONCLUSION: DICER1-altered thyroid lesions occurred frequently in young females and FNAs show RAS-like cytomorphology including crowded, mixed macro-/microfollicular pattern, and bland nuclear features. On resection, DICER1-altered thyroid lesions include benign (50%), low-risk lesions (30%), or high-risk malignancies (20%).


Assuntos
RNA Helicases DEAD-box , Mutação , Ribonuclease III , Neoplasias da Glândula Tireoide , Humanos , Ribonuclease III/genética , RNA Helicases DEAD-box/genética , Feminino , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Masculino , Biópsia por Agulha Fina , Adulto , Pessoa de Meia-Idade , Idoso , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/patologia , Adolescente , Criança , Adulto Jovem , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/patologia , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Glândula Tireoide/diagnóstico por imagem , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia
4.
Psychol Res ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526580

RESUMO

The recent review by Eaves et al. (Psychological Research/Psychologische Forschung, 2022) outlines the research conducted to-date on combined action-observation and motor imagery (AOMI), and more specifically, its added benefit to learning. Of interest, these findings have been primarily attributed to the dual action simulation hypothesis, whereby AO and MI activate separable representations for action that may be later merged when they are congruent with one another. The present commentary more closely evaluates this explanation. What's more, we offer an alternative information-based argument where the benefit to learning may be served instead by the availability of key information. Along these lines, we speculate on possible future directions including the need for a transfer design.

5.
Exp Brain Res ; 242(4): 921-935, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38329516

RESUMO

In rapid manual aiming, traditional wisdom would have it that two components manifest from feedback-based processes, where error accumulated within the primary submovement can be corrected within the secondary submovement courtesy of online sensory feedback. In some aiming contexts, there are more type 1 submovements (overshooting) compared to types 2 and 3 submovements (undershooting), particularly for more rapid movements. These particular submovements have also been attributed to a mechanical artefact involving movement termination and stabilisation. Hence, the goal of our study was to more closely examine the function of type 1 submovements by revisiting some of our previous datasets. We categorised these submovements according to whether the secondary submovement moved the limb closer (functional), or not (non-functional), to the target. Overall, there were both functional and non-functional submovements with a significantly higher proportion for the former. The displacement at the primary and secondary submovements, and negative velocity peak were significantly greater in the functional compared to non-functional. The influence of submovement type on other movement characteristics, including movement time, was somewhat less clear. These findings indicate that the majority of type 1 submovements are related to intended feedforward- and/or feedback-based processes, although there are a portion that can be attributed an indirect manifestation of a mechanical artefact. As a result, we suggest that submovements should be further categorised by their error-reducing function.


Assuntos
Movimento , Desempenho Psicomotor , Humanos , Extremidades
6.
Physiol Behav ; 269: 114284, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37394051

RESUMO

INTRODUCTION: Prolonged exercise has been linked to a decline in cognitive function due to a variety of factors, such as a drop in oxygen in the prefrontal cortex and an increase in stress hormones and neurotransmitters. Medium chain triglycerides (MCTs) may possibly offset this decline as they provide energy for the brain via both direct and indirect pathways, alongside promoting chronic physiological adaptations within the brain. METHODS: Participants were divided into two groups; MCT (n = 9) and Placebo (n = 10). The MCT gels contained 6 g of MCT with a C8:C10 ratio of 30:70, whereas the placebo gels contained carbohydrates of similar calorific value to the MCT gels. Participants visited the laboratory on three occasions (familiarisation/fitness test, pre-supplementation, post-supplementation), during which they performed a battery of cognitive tasks assessing domains such as processing speed, working memory, selective attention, decision making and coordination, before and after a prolonged bout of exercise (60 mins at 90% gas exchange threshold (GET). A 2-week supplementation period between visits 2 and 3 involved the ingestion of 2 gels per day. RESULTS: Exercise resulted in detriments in most cognitive tasks pre-supplementation for both groups, and post-supplementation for the Placebo group (main effect ps< 0.05). Post-supplementation, the effect of exercise was mediated in the MCT group for all cognitive tasks (main effect ps< 0.05), except for the Digit and Spatial Span Backwards test phases (main effect ps> 0.05). Furthermore, MCT supplementation enhanced before-exercise cognitive performance and in some measures, such as working memory, this was maintained after-exercise (interaction effect ps> 0.05). CONCLUSIONS: Chronic MCT supplementation enhanced before-exercise cognitive performance and offset the cognitive decline caused by a prolonged bout of exercise. In some cases, improvements in before-exercise cognitive performance were maintained after-exercise.


Assuntos
Disfunção Cognitiva , Exercício Físico , Adulto , Humanos , Cognição , Exercício Físico/fisiologia , Géis , Triglicerídeos/metabolismo
7.
Hum Mov Sci ; 89: 103085, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37030071

RESUMO

Motor learning can benefit from practice under enhanced expectancies; that is, the belief one can generate an intended positive outcome. According to the OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory, this benefit manifests from a greater coupling between action and its external consequences, which potentially coincides with a more automatic mode of control. The aim of the study was to examine this possibility, and in so doing, understand more about the psycho-motor processes underpinning the influence of expectancies. On Day 1, novice participants practiced a dart-throwing task under enhanced (EE) (n = 11), reduced (RE) (n = 12) or no (control; CTL) (n = 12) expectancies. Enhanced and reduced expectancies were indirectly manipulated by positively reinforcing shots that landed within the large or small circle on the dartboard, respectively. On Day 2, participants transferred to a dual-task (i.e., tone-counting) or stress (i.e., social-comparative threat, false feedback) setting. While there was no evidence of improvement across practice, RE was significantly worse than CTL for the dual-task, but EE was significantly worse than RE and CTL under stress (ps < 0.05). Therefore, the ability of EE to retain performance within the dual-task, but decline under stress, suggests a more automatic mode of control was adopted. Both theoretical and practical implications are discussed.


Assuntos
Aprendizagem , Desempenho Psicomotor , Humanos , Destreza Motora , Motivação , Atenção
8.
PLoS One ; 18(4): e0284936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37093873

RESUMO

The tendency to involuntarily imitate the actions of others (automatic imitation) can be modulated by social affiliative cues. Here, we explored whether the disruption to our social lives caused by the COVID-19 pandemic may subsequently influence automatic imitation. Three groups were initially presented a sentence comprehension task that featured either neutral (control), safe or unsafe primes to COVID-19 infection. They then completed an automatic imitation task, where a numeric cue was presented alongside apparent motion of an index or middle finger, which was either compatible or incompatible with the required response. Reaction times were longer for the incompatible compared to compatible trials, and thus demonstrated automatic imitation. However, there was no influence of the primes indicating that automatic imitation was unaffected by the risk of COVID-19. The potential theoretical explanations and practical implications of pathogen avoidance and social bonding incentives are discussed with reference to pandemic events.


Assuntos
COVID-19 , Comportamento Imitativo , Humanos , Comportamento Imitativo/fisiologia , Pandemias , Tempo de Reação , Sinais (Psicologia)
10.
JAMA Netw Open ; 5(10): e2239131, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36306129

RESUMO

Importance: Despite a widespread belief that private insurers spend large amounts on health care for enrollees receiving dialysis, data limitations over the past decade have precluded a comprehensive analysis of the topic. Objective: To examine the amount and types of increases in health care spending for privately insured patients associated with initiating dialysis care. Design, Setting, and Participants: A cohort study covering calendar years 2012 to 2019 included patients with kidney failure who had employer-sponsored insurance for 12 months following dialysis initiation. Data analysis was performed from August 27, 2021, to August 18, 2022. The data cover the entirety of the US and were obtained from the Health Care Cost Institute. The data include all medical claims for enrollees in employer-sponsored health insurance plans offered by multiple major health care insurers within the US. Participants included patients younger than 65 years who were continuously enrolled in these plans in the 12 months before and after their first claim for dialysis care. Patients also had to have nonmissing documented key characteristics, such as sex, race and ethnicity, and health characteristics. Exposures: A claim for dialysis care. Main Outcomes and Measures: Out-of-pocket, inpatient, outpatient, physician services, prescription medication, and total health care spending. The hypothesis tested was formulated before data collection. Results: The sample included 309 800 enrollee-months, which was a balanced panel of 25 months for 12 392 enrollees. At baseline, 7534 patients (61%) were male, 5415 (44%) were aged 55 to 64 years, and patients had been enrolled with their insurer for a mean of 30 months (95% CI, 29.9-30.1 months). In the 12 months before initiating dialysis care, total monthly health care spending was $5025 per patient per month (95% CI, $4945-$5106). Dialysis care initiation was associated with an increase in total monthly spending of $14 685 (95% CI, $14 413-$14 957). This increase occurred across all spending categories (dialysis, nondialysis outpatient, inpatient, physician services, and prescription drugs). Monthly patient out-of-pocket spending increased by $170 (95% CI, $162-$178). These spending increases occurred abruptly, beginning about 2 months before dialysis initiation, and remained increased for the subsequent 12 months. Conclusions and Relevance: In this cohort study, evidence that private insurers experience significant, sustained increases in spending when patients initiated dialysis was noted. The findings suggest that proposed policies aimed at limiting the amount dialysis facilities charge private insurers and the enrollees has the potential to reduce health care spending in this high-cost population.


Assuntos
Gastos em Saúde , Diálise Renal , Humanos , Masculino , Feminino , Estudos de Coortes , Seguradoras , Custos de Cuidados de Saúde
11.
JAMA Netw Open ; 5(4): e229581, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35486398

RESUMO

Importance: As private equity (PE) acquisitions of short-term acute care hospitals (ACHs) continue, their impact on the care of medically vulnerable older adults remains largely unexplored. Objective: To investigate the association between PE acquisition of ACHs and access to care, patient outcomes, and spending among Medicare beneficiaries hospitalized with acute medical conditions. Design, Setting, and Participants: This cross-sectional study used a generalized difference-in-differences approach to compare 21 091 222 patients admitted to PE-acquired vs non-PE-acquired short-term ACHs between January 1, 2001, and December 31, 2018, at least 3 years before to 3 years after PE acquisition. The analysis was conducted between December 28, 2020, and February 1, 2022. Differences were estimated using both facility and hospital service area fixed effects. To assess the robustness of findings, regressions were reestimated after including fixed effects of patient county of origin to account for geographic differences in underlying health risks. Two subset analyses were also conducted: (1) an analysis including only hospitals in hospital referral regions with at least 1 PE acquisition and (2) an analysis stratified by participation in the Hospital Corporation of America 2006 acquisition. The study included Medicare beneficiaries 66 years and older who were hospitalized with 1 of 5 acute medical conditions: acute myocardial infarction (AMI), acute stroke, chronic obstructive pulmonary disease exacerbation, congestive heart failure exacerbation, and pneumonia. Exposures: Acquisition of hospitals by PE firms. Main Outcomes and Measures: Comorbidity burden (measured by Elixhauser comorbidity score), hospital length of stay, in-hospital mortality, 30-day mortality, 30-day readmission, and 30-day episode payments. Results: Among 21 091 222 total Medicare beneficiaries admitted to ACHs between 2001 and 2018, 20 431 486 patients received care at non-PE-acquired hospitals, and 659 736 received care at PE-acquired hospitals. Across all admissions, the mean (SD) age was 79.45 (7.95) years; 11 727 439 patients (55.6%) were male, and 4 550 012 patients (21.6%) had dual insurance; 2 996 560 (14.2%) patients were members of racial or ethnic minority groups, including 2 085 128 [9.9%] Black and 371 648 [1.8%] Hispanic; 18 094 662 patients (85.8%) were White. Overall, 3 083 760 patients (14.6%) were hospitalized with AMI, 2 835 777 (13.4%) with acute stroke, 3 674 477 (17.4%) with chronic obstructive pulmonary disease exacerbation, 5 868 034 (27.8%) with congestive heart failure exacerbation, and 5 629 174 (26.7%) with pneumonia. Comorbidity burden decreased slightly among patients admitted with acute stroke (difference, -0.04 SDs; 95% CI, -0.004 to -0.07 SDs) at acquired hospitals compared with nonacquired hospitals but was unchanged across the other 4 conditions. Among patients with AMI, a greater decrease in in-hospital mortality was observed in PE-acquired hospitals compared with non-PE-acquired hospitals (difference, -1.14 percentage points, 95% CI, -1.86 to -0.42 percentage points). In addition, a greater decrease in 30-day mortality (difference, -1.41 percentage points; 95% CI, -2.26 to -0.56 percentage points) was found at acquired vs nonacquired hospitals. However, 30-day spending and readmission rates remained unchanged across all conditions. The extent and directionality of estimates were preserved across all robustness assessments and subset analyses. Conclusions and Relevance: In this cross-sectional study using a difference-in-differences approach, PE acquisition had no substantial association with the patient-level outcomes examined, although it was associated with a moderate improvement in mortality among Medicare beneficiaries hospitalized with AMI.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Pneumonia , Doença Pulmonar Obstrutiva Crônica , Acidente Vascular Cerebral , Doença Aguda , Idoso , Estudos Transversais , Etnicidade , Feminino , Hospitais , Humanos , Masculino , Medicare , Grupos Minoritários , Infarto do Miocárdio/epidemiologia , Pneumonia/epidemiologia , Estados Unidos/epidemiologia
12.
Diagn Cytopathol ; 50(7): 327-334, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35347884

RESUMO

BACKGROUND: Thyroid adenoma-associated (THADA) fusions are being identified more frequently with increased preoperative molecular testing on indeterminate thyroid fine-needle aspirates (FNA). However, data on cytomorphologic features of THADA-fusion thyroid lesions are limited. We examined cytomorphologic features of a THADA-fusion thyroid FNA cohort with clinical, radiologic, and histologic data. METHODS: Our THADA fusion FNA cohort included 11 specimens from 11 patients with a mean age and F:M ratio of 56.5 years and 2.7:1, respectively. Ten cases had FNA slides available for review and five cases had histopathology. Air-dried Diff-Quik and alcohol-fixed Papanicolaou smears, and formalin-fixed cell blocks were reviewed and findings were correlated with the matched resection, when available. Clinical and radiologic data were obtained from the medical record. RESULTS: THADA fusion thyroid lesions were hypoechoic or isoechoic (80%), solid (80%) with well-demarcated margins (100%) on ultrasound. Notable cytomorphologic features include crowded or prominent microfollicular groups (100%), scant colloid (91%), and mild nuclear atypia with nuclear grooves (100%), insignificant nuclear pleomorphism (100%), and without intranuclear pseudoinclusions (100%). All cases were classified as either atypia of undetermined significance (91%) or suspicious for follicular neoplasm (9%). Five resected cases were all low-risk lesions (benign and malignant) with no evidence of recurrence in the limited available follow-up. CONCLUSION: THADA-fusion thyroid FNAs show a crowded or prominent microfollicular pattern with mild nuclear atypia and without intranuclear pseudoinclusions, which overlaps with the cytomorphology of other RAS-like thyroid lesions. In our cohort, resected THADA lesions were low risk on histologic analysis.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Biópsia por Agulha Fina , Feminino , Fusão Gênica , Humanos , Hiperplasia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia
14.
J Mot Behav ; 54(4): 503-514, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34906031

RESUMO

For manual aiming, the optimized submovement model predicts a tendency toward target-center of primary movement endpoints (probabilistic strategy), while the minimization model predicts target undershooting ("play-it-safe" strategy). The spatial variability of primary movement endpoints directed toward a cross-hair (400-500 ms) (Session 1) were scaled by a multiplicative factor (x1 - 4) to form circular targets of different sizes (Session 2). In recognition of both models, it was predicted that the more that inherent variability exceeded the target size, the greater the tendency to shift from target-center aiming to target undershooting. The central tendency of primary movement endpoints was not influenced by the targets, while it neared target-center. These findings concur with a probabilistic strategy, although we speculate on factors that might otherwise foster a "play-it-safe" strategy.


Assuntos
Movimento , Desempenho Psicomotor , Humanos
15.
Hum Mov Sci ; 81: 102917, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34954624

RESUMO

The accuracy and precision of target-directed aiming is contingent upon the availability of online visual feedback. The present study aimed to examine the visual regulation of aiming with blurred vision. The aiming task was executed using a stylus on a graphics digitizing board, which was translated onto a screen in the form of a cursor (representing the moving limb) and target. The vision conditions involved the complete disappearance or blur of the cursor alone, target alone, and cursor+target. These conditions involved leaving the screen uncovered or covering with a diffusing sheet to induce blur. The distance between the screen and sheet was increased to make the blur progressively more severe (0 cm, 3 cm). Results showed significantly less radial and variable error under blurred compared to no vision of the cursor and cursor+target. These findings were corroborated by the movement kinematics including a shorter proportion of time to peak velocity, more negative within-participant correlation between the distances travelled to and after peak velocity, and lower spatial variability from peak velocity to the end of the movement under blurred vision. The superior accuracy and precision under the blurred compared to no vision conditions is consistent with functioning visual regulation of aiming, which is primarily contingent upon the online visual feedback of the moving limb. This outcome may be attributed to the processing of low spatial-high temporal frequencies. Potential implications for low vision diagnostics are discussed.


Assuntos
Retroalimentação Sensorial , Movimento , Fenômenos Biomecânicos , Retroalimentação , Humanos , Desempenho Psicomotor , Visão Ocular , Percepção Visual
16.
Motor Control ; 25(3): 349-368, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33811190

RESUMO

The failure of perceptual illusions to elicit corresponding biases within movement supports the view of two visual pathways separately contributing to perception and action. However, several alternative findings may contest this overarching framework. The present study aimed to examine the influence of perceptual illusions within the planning and control of aiming. To achieve this, we manipulated and measured the planning/control phases by respectively perturbing the target illusion (relative size-contrast illusion; Ebbinghaus/Titchener circles) following movement onset and detecting the spatiotemporal characteristics of the movement trajectory. The perceptual bias that was indicated by the perceived target size estimates failed to correspondingly manifest within the effective target size. While movement time (specifically, time after peak velocity) was affected by the target configuration, this outcome was not consistent with the direction of the perceptual illusions. These findings advocate an influence of the surrounding contextual information (e.g., annuli) on movement control that is independent of the direction predicted by the illusion.


Assuntos
Artefatos , Viés , Ilusões , Humanos , Movimento , Desempenho Psicomotor , Percepção Visual
17.
Exp Brain Res ; 239(5): 1479-1488, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33683404

RESUMO

The task constraints imposed upon a co-actor can often influence our own actions. Likewise, the observation of somebody else's movements can involuntarily contaminate the execution of our own movements. These joint action outcomes have rarely been considered in unison. The aim of the present study was to simultaneously examine the underlying processes contributing to joint action. We had pairs of participants work together to execute sequential aiming movements between two targets-the first person's movement was contingent upon the anticipation of the second person's movement (leader), while the second person's movement was contingent upon the direct observation of the first person's movement (follower). Participants executed separate blocks of two-target aiming movements under different contexts; that is, solely on their own using one (2T1L) and two (2T2L) of their upper limbs, or with another person (2T2P). The first movement segment generally indicated a more abrupt approach (shorter time after peak velocity, greater displacement and magnitude of peak velocity), which surprisingly coincided with lower spatial variability, for the 2T2P context. Meanwhile, the second segment indicated a similar kinematic profile as the first segment for the 2T2P context. The first movement of the leader appeared to accommodate the follower for their movement, while the second movement of the follower was primed by the observation of the leader's movement. These findings collectively advocate two distinct levels of joint action including the anticipation (top-down) and mapping (bottom-up) of other people's actions.


Assuntos
Movimento , Desempenho Psicomotor , Fenômenos Biomecânicos , Humanos
18.
Hum Mov Sci ; 76: 102773, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33636571

RESUMO

Attentional Control Theory states that anxiety can cause attention to be allocated to irrelevant sources of information by hindering the ability to control attention and focus on the information that matters. In a separate line of inquiry, action-centred views of attention state that non-target distractors involuntarily activate response codes that may cause interference with target-directed movements (distractor interference effect). Due to the proposed negative effects of anxiety on attentional control, we examined whether anxiety could also modulate distractor interference. Participants executed target-directed aiming movements to one of three targets with the potential of a distractor being presented at near or far locations. Distractors were presented at different times with respect to the target presentation in order to explore the excitatory (0, -100 ms) and inhibitory (-850 ms) processing of the distractor. As a broad indication of the effect of anxiety, the analysis of no distractor trials indicated a lower proportion of time and displacement to reach peak velocity under high compared to low anxiety conditions. Meanwhile, the typical excitatory influence of the distractors located near, compared to far, at a short distractor-onset asynchrony was found in movement time and overall response time. However, this distractor excitation was even greater under high compared to low anxiety in the reaction time component of the response. These findings broadly implicate the attentional control perspective, but they further indicate an influence of anxiety on the excitation rather than inhibition of responses.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Atenção , Cognição/fisiologia , Inibição Psicológica , Tempo de Reação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Destreza Motora , Adulto Jovem
19.
Physiol Behav ; 229: 113252, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33220329

RESUMO

PURPOSE: The brain can utilise medium chain triglycerides (MCTs) as an alternative fuel to glucose, and research has shown that MCT ingestion improves cognitive function in diseased and/or elderly individuals. The aim of this study is to determine if these improvements can also be observed in young, healthy adults. Furthermore, we aim to establish the ideal dosage and timeframe necessary for an effect. METHODS: Participants were divided equally into three groups of 10 (Placebo (0 g), 12 g and 18 g MCT/day) and were supplemented for 4 weeks. The supplement had a C8:C10 ratio of 30:70. Participants visited the laboratory once a week for 5 weeks (baseline, test weeks 1-4) to undergo a battery of cognitive tests; Trail Making, Digit Span, Spatial Span, Covert Shift of Attention, and Rapid Visual Information Processing. RESULTS: After 2-3 weeks of supplementation, MCT ingestion enhanced performance in cognitive tasks, including: Trail Making A/B and Digit Span Forwards/Backwards (ps<0.001) when compared to a placebo group taking a carbohydrate gel. In Spatial Span Backwards, there was a significant main effect of group (p = 0.002). Where significance was seen, there were main effects of time after 2-3 weeks (ps<0.05). There was minimal difference between the two MCT intervention groups in most measures (ps>0.05). There were also null results in tasks measuring attention and reaction time (ps>0.05). CONCLUSIONS: MCT ingestion improved cognitive performance after 2-3 weeks, with minimal difference between taking 12 g and 18 g MCT/day groups, suggesting a possible dose-response threshold at 12 g MCT/day when supplementing over a short period.


Assuntos
Cognição , Suplementos Nutricionais , Idoso , Encéfalo , Humanos , Testes Neuropsicológicos , Triglicerídeos , Adulto Jovem
20.
Sci Med Footb ; 5(3): 181-187, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-35077295

RESUMO

Purpose: There isgrowing concern surrounding the harmful effects of soccer heading on cognitive function. The present study aims to examine the immediate effects of heading.Methods: 30 recreational male soccer players were divided into three groups that undertook 20 consecutive headers with a soft (8.8 psi), hard (16.2 psi), or no (control) ball. A battery of neuropsychological tests was completed before and after heading: King-Devick, trail-making (TM) (A, B), digit span (DS) and spatial span (SS) (forward, backward).Results: Significant increase in the time (M = 4.44 s) and errors (M = 1.45) for the King-Devick test within the hard and soft groups, although there was no significant difference for TM-A and TM-B. Significant decline for SS forward within the hard and soft groups (M= -16%), although the declines for SS backward (M = -16%), DS forward (M= -23%) and DS backward (M = -25%) were present only for the hard group (ps <.05).Discussion: While outside of regular match-play, this study showed that heading negatively influenced one indicator of a suspected concussion (King-Devick), as well as working memory (DS, SS) that is essential for daily life. These findings contribute to the growing debate surrounding heading safety.


Assuntos
Concussão Encefálica , Futebol , Concussão Encefálica/diagnóstico , Cognição , Humanos , Masculino , Memória de Curto Prazo , Testes Neuropsicológicos
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