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1.
Gerontology ; 70(4): 429-438, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38219728

RESUMO

INTRODUCTION: Current cognitive assessments suffer from floor/ceiling and practice effects, poor psychometric performance in mild cases, and repeated assessment effects. This study explores the use of digital speech analysis as an alternative tool for determining cognitive impairment. The study specifically focuses on identifying the digital speech biomarkers associated with cognitive impairment and its severity. METHODS: We recruited older adults with varying cognitive health. Their speech data, recorded via a wearable microphone during the reading aloud of a standard passage, were processed to derive digital biomarkers such as timing, pitch, and loudness. Cohen's d effect size highlighted group differences, and correlations were drawn to the Montreal Cognitive Assessment (MoCA). A stepwise approach using a Random Forest model was implemented to distinguish cognitive states using speech data and predict MoCA scores based on highly correlated features. RESULTS: The study comprised 59 participants, with 36 demonstrating cognitive impairment and 23 serving as cognitively intact controls. Among all assessed parameters, similarity, as determined by Dynamic Time Warping (DTW), exhibited the most substantial positive correlation (rho = 0.529, p < 0.001), while timing parameters, specifically the ratio of extra words, revealed the strongest negative correlation (rho = -0.441, p < 0.001) with MoCA scores. Optimal discriminative performance was achieved with a combination of four speech parameters: total pause time, speech-to-pause ratio, similarity via DTW, and intelligibility via DTW. Precision and balanced accuracy scores were found to be 88.1 ± 1.2% and 76.3 ± 1.3%, respectively. DISCUSSION: Our research proposes that reading-derived speech data facilitates the differentiation between cognitively impaired individuals and cognitively intact, age-matched older adults. Specifically, parameters based on timing and similarity within speech data provide an effective gauge of cognitive impairment severity. These results suggest speech analysis as a viable digital biomarker for early detection and monitoring of cognitive impairment, offering novel approaches in dementia care.


Assuntos
Disfunção Cognitiva , Fala , Humanos , Idoso , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Cognição , Testes de Estado Mental e Demência , Biomarcadores
2.
Ann Thorac Surg ; 117(3): 635-643, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37517533

RESUMO

BACKGROUND: Technical skill is essential for good outcomes in cardiac surgery. However, no objective methods exist to measure dexterity while performing surgery. The purpose of this study was to validate sensor-based hand motion analysis (HMA) of technical dexterity while performing a graft anastomosis within a validated simulator. METHODS: Surgeons at various training levels performed an anastomosis while wearing flexible sensors (BioStamp nPoint, MC10 Inc) with integrated accelerometers and gyroscopes on each hand to quantify HMA kinematics. Groups were stratified as experts (n = 8) or novices (n = 18). The quality of the completed anastomosis was scored using the 10 Point Microsurgical Anastomosis Rating Scale (MARS10). HMA parameters were compared between groups and correlated with quality. Logistic regression was used to develop a predictive model from HMA parameters to distinguish experts from novices. RESULTS: Experts were faster (11 ± 6 minutes vs 21 ± 9 minutes; P = .012) and used fewer movements in both dominant (340 ± 166 moves vs 699 ± 284 moves; P = .003) and nondominant (359 ± 188 moves vs 567 ± 201 moves; P = .02) hands compared with novices. Experts' anastomoses were of higher quality compared with novices (9.0 ± 1.2 MARS10 vs 4.9 ± 3.2 MARS10; P = .002). Higher anastomosis quality correlated with 9 of 10 HMA parameters, including fewer and shorter movements of both hands (dominant, r = -0.65, r = -0.46; nondominant, r = -0.58, r = -0.39, respectively). CONCLUSIONS: Sensor-based HMA can distinguish technical dexterity differences between experts and novices, and correlates with quality. Objective quantification of hand dexterity may be a valuable adjunct to training and education in cardiac surgery training programs.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cirurgiões , Humanos , Mãos , Anastomose Cirúrgica , Movimento (Física) , Competência Clínica
3.
Sensors (Basel) ; 23(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37430862

RESUMO

Aggression in children is highly prevalent and can have devastating consequences, yet there is currently no objective method to track its frequency in daily life. This study aims to investigate the use of wearable-sensor-derived physical activity data and machine learning to objectively identify physical-aggressive incidents in children. Participants (n = 39) aged 7 to 16 years, with and without ADHD, wore a waist-worn activity monitor (ActiGraph, GT3X+) for up to one week, three times over 12 months, while demographic, anthropometric, and clinical data were collected. Machine learning techniques, specifically random forest, were used to analyze patterns that identify physical-aggressive incident with 1-min time resolution. A total of 119 aggression episodes, lasting 7.3 ± 13.1 min for a total of 872 1-min epochs including 132 physical aggression epochs, were collected. The model achieved high precision (80.2%), accuracy (82.0%), recall (85.0%), F1 score (82.4%), and area under the curve (89.3%) to distinguish physical aggression epochs. The sensor-derived feature of vector magnitude (faster triaxial acceleration) was the second contributing feature in the model, and significantly distinguished aggression and non-aggression epochs. If validated in larger samples, this model could provide a practical and efficient solution for remotely detecting and managing aggressive incidents in children.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Humanos , Criança , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Aceleração , Agressão , Exercício Físico , Aprendizado de Máquina
4.
Artigo em Inglês | MEDLINE | ID: mdl-36078500

RESUMO

Maintaining function in older adults is key to the quality of life and longevity. This study examined the potential impact of falls on accelerating further deterioration over time in gait, balance, physical activity, depression, fear of falling, and motor capacity in older adults. 163 ambulatory older adults (age = 76.5 ± 7.7 years) participated and were followed for 6 months. They were classified into fallers or non-fallers based on a history of falling within the past year. At baseline and 6 months, all participants were objectively assessed for gait, balance, and physical activity using wearable sensors. Additional assessments included psychosocial concerns (depression and fear of falling) and motor capacity (Timed Up and Go test). The fallers showed lower gait performance, less physical activity, lower depression level, higher fear of falling, and less motor capacity than non-fallers at baseline and 6-month follow-up. Results also revealed acceleration in physical activity and motor capacity decline compared to non-fallers at a 6-month follow-up. Our findings suggest that falls would accelerate deterioration in both physical activity and motor performance and highlight the need for effective therapy to reduce the consequences of falls in older adults.


Assuntos
Acidentes por Quedas , Medo , Acidentes por Quedas/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Depressão , Exercício Físico , Medo/psicologia , Seguimentos , Marcha , Humanos , Equilíbrio Postural , Qualidade de Vida , Estudos de Tempo e Movimento
5.
Sci Rep ; 11(1): 15959, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354213

RESUMO

Mirror Neurons (MNs) respond similarly when primates make or observe grasping movements. Recent work indicates that reward expectation influences rostral M1 (rM1) during manual, observational, and Brain Machine Interface (BMI) reaching movements. Previous work showed MNs are modulated by subjective value. Here we expand on the above work utilizing two non-human primates (NHPs), one male Macaca Radiata (NHP S) and one female Macaca Mulatta (NHP P), that were trained to perform a cued reward level isometric grip-force task, where the NHPs had to apply visually cued grip-force to move and transport a virtual object. We found a population of (S1 area 1-2, rM1, PMd, PMv) units that significantly represented grip-force during manual and observational trials. We found the neural representation of visually cued force was similar during observational trials and manual trials for the same units; however, the representation was weaker during observational trials. Comparing changes in neural time lags between manual and observational tasks indicated that a subpopulation fit the standard MN definition of observational neural activity lagging the visual information. Neural activity in (S1 areas 1-2, rM1, PMd, PMv) significantly represented force and reward expectation. In summary, we present results indicating that sensorimotor cortices have MNs for visually cued force and value.


Assuntos
Neurônios-Espelho/fisiologia , Motivação/fisiologia , Córtex Sensório-Motor/fisiologia , Potenciais de Ação/fisiologia , Animais , Interfaces Cérebro-Computador , Sinais (Psicologia) , Feminino , Força da Mão/fisiologia , Macaca mulatta/fisiologia , Macaca radiata/fisiologia , Masculino , Neurônios-Espelho/metabolismo , Córtex Motor/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Recompensa
6.
Heliyon ; 4(12): e01053, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30582058

RESUMO

Quadruped robots can mimic animal walking gait and they have certain advantages like walking on terrain and extremely rough surfaces. Obstacles can impede the movement of wheeled vehicles, where a quadruped can adapt to avoid obstacles by adjusting its height. A quadruped robot is designed and developed for in this paper, which could be controlled by the Android operating system. The Inverse Kinematics Solutions are derived for the developed structure using Denavit-Hartenberg convention and using those solutions the movements are simulated using a custom-made 3D software. An Android application is developed, which is able to control the robot using Bluetooth. The robot currently has following six different movements: front, back, left, right walking, clockwise and anti-clockwise rotation. The robot uses the ultrasound sensor to detect any obstacle closer than 300 cm (maximum) and if an impediment appears, the robot will automatically move parallel to the obstacle until it is avoided. Currently, it can move at a speed of 15.5 cm/s (approximately). To complete a full rotation of 360°, it takes 6 seconds. It can be used to develop and implement any autonomous path-planning algorithm.

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