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1.
J Man Manip Ther ; : 1-11, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363078

RESUMO

CONTEXT: Forward shoulder posture (FSP) is a risk factor for shoulder pathology. Manual therapists often use myofascial release (MFR) to elongate restricted pectoral fascia to reduce FSP and improve shoulder function; however, the effects of this treatment approach remain anecdotal. OBJECTIVE: Determine the acute effects of 4-min of MFR, compared to a soft-touch control (CON), to the pectoral fascia on: 1) FSP, 2) shoulder horizontal abduction ROM (HA-ROM), and 3) muscle excitation of the trapezius (upper, middle, lower [UT, MT, LT]) and pectoralis major (PEC). METHODS: Fifty-nine right-handed participants (27 ± 9 years, 30 female) with FSP, but otherwise asymptomatic shoulders participated in a randomized crossover clinical trial by attending two experimental sessions: one MFR and one CON treatment, each administered by a Registered Massage Therapist. FSP, HA-ROM, and muscle excitation during a reaching task, were measured before and after each treatment. RESULTS: There was a significant interaction between treatment and time for FSP (p = .018, ηp = .093) with FSP decreasing from PRE MFR (128 ± 19 mm) to POST MFR (123 ± 19 mm; p < .001, ηp = .420) and PRE CON (126 ± 19 mm) to POST CON (124 ± 18 mm; p < .001, ηp = .191) interventions. There were no significant differences in HA-ROM or muscle excitation. CONCLUSION: Four minutes of MFR or CON to the pectoral fascia acutely reduces FSP.

2.
J Mot Behav ; 56(1): 1-13, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37394465

RESUMO

A 'violation' of Fitts' Law, or Fitts' Equation, occurs when each potential target location is outlined before and during a reaching movement. Past studies have measured the violation in highly controlled laboratory environments, limiting the generalizability of findings. The purpose of the study was to replicate the violation of Fitts' Equation in the homes of participants using a novel portable apparatus during the COVID-19 pandemic. Movements were measured independently with an accelerometer and touch screen, which allowed for kinematic, temporal, and spatial outcomes to be measured in remote environments. The violation of Fitts' Equation was found with the touch and acceleration measurements and was thus seen in ecologically valid environments. The apparatus used may be used as a model for future field research.


Assuntos
Pandemias , Desempenho Psicomotor , Humanos , Movimento , Fenômenos Biomecânicos
3.
Exp Brain Res ; 242(2): 429-442, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147086

RESUMO

Müller-Lyer (ML) figures bias size estimation consistently, yet different methods can lead to different degrees of illusory bias. Autistic individuals may also be less likely to perceive illusory biases with varying levels of autistic trait expression proposed to modulate reported illusory biases. The Autism-Spectrum Quotient (AQ) and Systemizing Quotient (SQ) are self-report measures that quantify autistic trait expression and systemizing ability in neurotypical individuals. The current study sought to determine if perceptions of illusory size bias negatively correlate with autistic trait expression and the extent to which varying methods of illusion presentation change the magnitude of illusory bias. Thirty neurotypical adults completed both questionnaires as well as four size estimation tasks. Two tasks involved perceptual discrimination of ML figures by concurrent and successive presentation, where participants selected the longer figure by keypress. For Tasks 3 and 4, participants adjusted the size of a non-illusory line (Task 3) or complementary illusory figure (Task 4) to match the perceived length. Overall, task performance was not correlated with autistic trait expression. One exception was a negative correlation with AQ when adjusting a complementary illusory ML figure in Task 4. Illusory biases were also stronger when two illusory figures were presented concurrently. Given these results, illusion susceptibility to the ML is suggested to be reduced with increases in AQ, but only when the method of illusion measurement is adjustment of concurrent illusory figures. Taken together the results provide evidence that traits associated with autism in a neurotypical population may systematically modulate perception.


Assuntos
Transtorno Autístico , Ilusões Ópticas , Adulto , Humanos , Percepção de Tamanho , Fenótipo , Autorrelato
4.
Somatosens Mot Res ; : 1-16, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906183

RESUMO

AIMS: Application of muscle-tendon vibration within the frequency range of 70-120Hz has been studied as a tool to stimulate somatosensory afferents with both the goal of studying human sensorimotor control and of improving post-stroke motor performance. Specific to applications for rehabilitation, current evidence is mixed as to whether dual muscle-tendon vibration is detrimental to the performance of goal-directed upper-limb movements. The current study aimed to determine the effects of muscle-tendon vibration over the wrist flexors and extensors (dual vibration) on performance of a computer goal-directed aiming task. METHODS: Twenty healthy participants were assigned to the vibration or control group. An aiming task that involved acquiring targets by moving an unseen cursor on a screen was performed. Vision of the cursor and hand were unavailable throughout the four blocks of movement execution. Only the vibration group received dual vibration throughout four blocks. Task performance was assessed using measures of endpoint accuracy and timing. Perceived hand location was assessed using a set of questions and a computerised conscious perception task. RESULTS: The vibration group had significantly shorter reaction times, without any change in endpoint accuracy, indicating more efficient and effective movement planning. The vibration group did report illusory movement sensation, which was reduced by block 4. CONCLUSIONS: Dual vibration did not adversely affect aiming accuracy and showed some improvement in reaction time. The present findings support the potential for using dual vibration to stimulate the somatosensory system as participants improved their performance of a novel goal-directed movement. Notably, improvements were maintained when the vibration was removed.

5.
Brain Sci ; 13(9)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37759903

RESUMO

Two experiments were conducted to assess the impact of induced paresthesia on movement parameters of goal-directed aiming movements to determine how visual and auditory feedback may enhance performance when somatosensory feedback is disrupted. In both experiments, neurotypical adults performed the goal-directed aiming task in four conditions: (i) paresthesia-full vision; (ii) paresthesia-no vision; (iii) no paresthesia-full vision; (iv) no paresthesia-no vision. Targets appeared on a computer screen, vision was obscured using visual occlusion spectacles, and paresthesia was induced with a constant current stimulator. The first and last 20% of trials (early and late performance) were compared to assess adaptability to altered somatosensory input. Experiment 2 added an auditory tone that confirmed successful target acquisitions. When compared to early performance in the no-paresthesia and no-vision conditions, induced paresthesia and no vision led to significantly larger endpoint error toward the body midline in both early and late performance. This finding reveals the importance of proprioceptive input for movement accuracy in the absence of visual feedback. The kinematic results indicated that vision could not fully compensate for the disrupted proprioceptive input when participants experienced induced paresthesia. However, when auditory feedback confirmed successful aiming movements in Experiment 2, participants were able to improve their endpoint variability when experiencing induced paresthesia through changes in movement preparation.

6.
Brain Sci ; 13(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37759942

RESUMO

The current study investigated how temporarily induced paresthesia in the moving limb affects the performance of a goal-directed target aiming task. Three-dimensional displacement data of 14 neurotypical participants were recorded while they pointed to a target on a computer monitor in four conditions: (i) paresthesia-full-vision; (ii) paresthesia-without-target vision; (iii) no-paresthesia-full-vision; (iv) no paresthesia-without-target vision. The four conditions were blocked and counterbalanced such that participants performed the paresthesia and no-paresthesia conditions on two separate days. To assess how aiming performance changed in the presence of paresthesia, we compared early versus late performance (first and last 20% of trials). We found that endpoint accuracy and movement speed were reduced in the presence of paresthesia, but only without target vision. With repetition, participants adjusted their movement performance strategy, such that with induced paresthesia, they used a movement strategy that included more pre-planned movements that depended less on online control.

7.
Exp Brain Res ; 241(10): 2451-2461, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37653104

RESUMO

According to Fitts' Law, the time to reach a target (movement time, MT) increases with distance. A violation of Fitts' Law occurs when target positions are outlined before and during movement, as MTs are not different when reaching to the farthest and penultimate targets. One hypothesis posits that performers cognitively process the edges of a target array before the center, allowing for corrective movements to be completed more quickly when moving to edge targets compared to middle targets. The objective of this study was to test this hypothesis by displaying a target range rather than outlines of individual targets in an effort to identify the effects of array edges. Using a touch-screen laptop, participants (N = 24) were asked to reach to one of three targets which would appear within a presented range. Separately, targets were also presented without a range to determine if the display protocol could evoke Fitts' Law. Movements were assessed with the touch screen and optical position measurement. A main effect was found for relative position within a range (touch: F2,44 = 15.4, p < 0.001, η2p = 0.412; position: F2,40 = 15.6, p < 0.001, η2p = 0.439). As hypothesised, MT to the farthest target in a range was not significantly different than MT to the middle target (touch: p = 0.638, position: p = 0.449). No violation was found when a target range was not presented (touch: p = 0.003, position: p = 0.001). Thus, a target range reproduces the Fitts' Law violation previously documented with individually outlined targets, which supports and extends the discussed hypothesis.


Assuntos
Resinas Acrílicas , Ácido Dioctil Sulfossuccínico , Humanos , Movimento , Fenolftaleína , Puromicina
8.
Disabil Rehabil ; : 1-8, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37272778

RESUMO

PURPOSE: Dance can encourage physical activity and promote physical, cognitive, and social development for adults who have neurodevelopmental disabilities (NDD). Dance is defined as a form of expression that may be structured, exploratory, and/or cultural. Current literature supports the benefits of participation in dance for persons with NDD, however less is known about what characteristics support participation in dance. MATERIALS AND METHODS: A scoping review was conducted to synthesize the characteristics of dance interventions, teaching strategies, and outcome measures used to assess the efficacy of dance interventions. Searches were conducted across six databases and the results were screened according to: i) adults ≥18yrs of age with a diagnosed NDD, and ii) the program incorporated activities that fall within our definition of dance. RESULTS: A range of dance forms and NDDs were represented across the fourteen studies reviewed. Few provided explicit details of the dance interventions, nor how instruction was adapted. All studies that measured fitness, mobility, balance, posture, and functional activity showed significant improvement. Studies that measured psychosocial and well-being focused on autistic characteristics and showed mixed results. CONCLUSIONS: Details of interventions, instructions, measures of movement performance, and the relationship between outcomes and the interventions require further development and research.IMPLICATIONS FOR REHABILITATIONDance is a multimodal activity that can improve aerobic capacity, postural control, passive ROM, and strength in adults with neurodevelopmental disability at all levels of function.Participation in dance may be recommended as an option for recreational physical activity as current evidence supports dance as an effective physical activity, and/or supplement to therapeutic goals, with physiological as well as psychosocial benefits.When considering dance as a recreational activity it is important to consider the program and instructors approach, as well as the experience and training of the instructor, in order to best match the goals of the dancer with the goals of the specific program.

9.
Brain Sci ; 13(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36831913

RESUMO

Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder, where differences are often present relating to the performance of motor skills. Our previous work elucidated unique event-related potential patterns of neural activity in those with ADHD when performing visuomotor and force-matching motor paradigms. The purpose of the current study was to identify whether there were unique neural sources related to somatosensory function and motor performance in those with ADHD. Source localization (sLORETA) software identified areas where neural activity differed between those with ADHD and neurotypical controls when performing a visuomotor tracing task and force-matching task. Median nerve somatosensory evoked potentials (SEPs) were elicited, while whole-head electroencephalography (EEG) was performed. sLORETA localized greater neural activity post-FMT in those with ADHD, when compared with their baseline activity (p < 0.05). Specifically, greater activity was exhibited in BA 31, precuneus, parietal lobe (MNI coordinates: X = -5, Y = -75, and Z = 20) at 156 ms post stimulation. No significant differences were found for any other comparisons. Increased activity within BA 31 in those with ADHD at post-FMT measures may reflect increased activation within the default mode network (DMN) or attentional changes, suggesting a unique neural response to the sensory processing of force and proprioceptive afferent input in those with ADHD when performing motor skills. This may have important functional implications for motor tasks dependent on similar proprioceptive afferent input.

10.
Brain Sci ; 12(6)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35741694

RESUMO

Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that exhibits unique neurological and behavioural characteristics. Our previous work using event-related potentials demonstrated that adults with ADHD process audiovisual multisensory stimuli somewhat differently than neurotypical controls. This study utilised an audiovisual multisensory two-alternative forced-choice discrimination task. Continuous whole-head electroencephalography (EEG) was recorded. Source localization (sLORETA) software was utilised to determine differences in the contribution made by sources of neural generators pertinent to audiovisual multisensory processing in those with ADHD versus neurotypical controls. Source localization techniques elucidated that the controls had greater neural activity 164 ms post-stimulus onset when compared to the ADHD group, but only when responding to audiovisual stimuli. The source of the increased activity was found to be Brodmann Area 2, postcentral gyrus, right-hemispheric parietal lobe referenced to Montreal Neurological Institute (MNI) coordinates of X = 35, Y = −40, and Z = 70 (p < 0.05). No group differences were present during either of the unisensory conditions. Differences in the integration areas, particularly in the right-hemispheric parietal brain regions, were found in those with ADHD. These alterations may correspond to impaired attentional capabilities when presented with multiple simultaneous sensory inputs, as is the case during a multisensory condition.

11.
Front Hum Neurosci ; 16: 1078925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684834

RESUMO

Introduction: Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that exhibits unique neurological and behavioral characteristics. Those with ADHD often have noted impairments in motor performance and coordination, including during tasks that require force modulation. The present study provides insight into the role of altered neural processing and SMI in response to a motor learning paradigm requiring force modulation and proprioception, that previous literature has suggested to be altered in those with ADHD, which can also inform our understanding of the neurophysiology underlying sensorimotor integration (SMI) in the general population. Methods: Adults with ADHD (n = 15) and neurotypical controls (n = 15) performed a novel force-matching task, where participants used their right-thumb to match a trace template that varied from 2-12% of their Abductor Pollicis Brevis maximum voluntary contraction. This motor task was completed in pre, acquisition, and post blocks. Participants also completed a retention test 24 h later. Median nerve somatosensory-evoked potentials (SEPs) were collected pre and post motor acquisition. SEPs were stimulated at two frequencies, 2.47 Hz and 4.98 Hz, and 1,000 sweeps were recorded using 64-electrode electroencephalography (EEG) at 2,048 Hz. SEP amplitude changes were normalized to each participant's baseline values for that peak. Results: Both groups improved at post measures (ADHD: 0.85 ± 0.09; Controls: 0.85 ± 0.10), with improvements maintained at retention (ADHD: 0.82 ± 0.11; Controls: 0.82 ± 0.11). The ADHD group had a decreased N18 post-acquisition (0.87 ± 0.48), while the control N18 increased (1.91 ± 1.43). The N30 increased in both groups, with a small increase in the ADHD group (1.03 ± 0.21) and a more pronounced increase in controls (1.15 ± 0.27). Discussion: Unique neural differences between groups were found after the acquisition of a novel force-matching motor paradigm, particularly relating to the N18 peak. The N18 differences suggest that those with ADHD have reduced olivary-cerebellar-M1 inhibition when learning a novel motor task dependent on force-modulation, potentially due to difficulties integrating the afferent feedback necessary to perform the task. The results of this work provide evidence that young adults with ADHD have altered proprioceptive processing when learning a novel motor task when compared to neurotypical controls.

12.
Adapt Phys Activ Q ; 39(1): 1-16, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740992

RESUMO

Improvements in functional reaching directly support improvements in independence. The addition of auditory inputs (e.g., music, rhythmic counting) may improve goal-directed reaching for individuals with cerebral palsy (CP). To effectively integrate auditory stimuli into adapted teaching and rehabilitation protocols, it is necessary to understand how auditory stimuli may enhance limb control. This study considered the influence of auditory stimuli during the planning or execution phases of goal-directed reaches. Adults (with CP = 10, without CP = 10) reached from a home switch to two targets. Three conditions were presented-no sound, sound before, and sound during-and three-dimensional movement trajectories were recorded. Reaction times were shorter for both groups in the sound before condition, while the group with CP also reached peak velocity relatively earlier in the sound before condition. The group with CP executed more consistent movements in both sound conditions. Sound presented before movement initiation improved both the planning and execution of reaching movements for adults with CP.


Assuntos
Paralisia Cerebral , Adulto , Objetivos , Humanos , Motivação , Movimento , Desempenho Psicomotor , Tempo de Reação
13.
J Mot Behav ; 54(1): 67-79, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33715604

RESUMO

Music and metronomes differentially impact movement performance. The current experiment presented metronome and drum beats in simple and complex rhythms before goal-directed reaching movements, while also quantifying enjoyment. Auditory conditions were completed with and without visual feedback and were blocked and counterbalanced. There were no differences between simple and complex rhythms, indicating that rhythmic information alone is sufficient to benefit performance. The drum elicited shorter movement times and higher peak velocities, without an increase in spatial variability. Reaction times were moderately correlated with ratings of enjoyment. These data provide evidence that the source of an auditory stimulus impacts movement performance of a goal-directed reaching task. Results are contextualized within models of goal-directed reaching to elucidate mechanisms contributing to performance improvements.


Assuntos
Objetivos , Desempenho Psicomotor , Estimulação Acústica , Percepção Auditiva , Humanos , Motivação , Movimento , Tempo de Reação
14.
Hum Mov Sci ; 79: 102846, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34303054

RESUMO

Rhythmic auditory stimuli presented before a goal-directed movement have been found to improve temporal and spatial movement outcomes. However, little is known about the mechanisms mediating these benefits. The present experiment used three types of auditory stimuli to probe how improved scaling of movement parameters, temporal preparation and an external focus of attention may contribute to changes in movement performance. Three types of auditory stimuli were presented for 1200 ms before movement initiation; three metronome beats (RAS), a tone that stayed the same (tone-same), a tone that increased in pitch (tone-change) and a no sound control, were presented with and without visual feedback for a total of eight experimental conditions. The sound was presented before a visual go-signal, and participants were instructed to reach quickly and accurately to one of two targets randomly identified in left and right hemispace. Twenty-two young adults completed 24 trials per blocked condition in a counterbalanced order. Movements were captured with an Optotrak 3D Investigator, and a 4(sound) by 2(vision) repeated measures ANOVA was used to analyze dependant variables. All auditory conditions had shorter reaction times than no sound. Tone-same and tone-change conditions had shorter movement times and higher peak velocities, with no change in trajectory variability or endpoint error. Therefore, rhythmic and non-rhythmic auditory stimuli impacted movement performance differently. Based on the pattern of results we propose multiple mechanisms impact movement planning processes when rhythmic auditory stimuli are present.


Assuntos
Atenção , Movimento , Estimulação Acústica , Retroalimentação Sensorial , Humanos , Desempenho Psicomotor , Tempo de Reação , Visão Ocular , Adulto Jovem
15.
Brain Sci ; 10(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316939

RESUMO

Nerve paresthesia is a sensory impairment experienced in clinical conditions such as diabetes. Paresthesia may "mask" or "compete" with meaningful tactile information in the patient's sensory environment. The two objectives of the present study were: (1) to determine if radiating paresthesia produces a peripheral mask, a central mask, or a combination; (2) to determine if a response competition experimental design reveals changes in somatosensory integration similar to a masking design. Experiment 1 assessed the degree of masking caused by induced radiating ulnar nerve paresthesia (a concurrent non-target stimulus) on a vibrotactile Morse code letter acquisition task using both behavioral and neurophysiological measures. Experiment 2 used a response competition design by moving the radiating paresthesia to the median nerve. This move shifted the concurrent non-target stimulus to a location spatially removed from the target stimuli. The task, behavioral and neurophysiological measures remained consistent. The induced paresthesia impacted letter acquisition differentially depending on the relative location of meaningful and non-meaningful stimulation. Paresthesia acted as a peripheral mask when presented to overlapping anatomical stimulation areas, and a central mask when presented at separate anatomical areas. These findings are discussed as they relate to masking, subcortical, and centripetal gating.

16.
Gait Posture ; 82: 100-105, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32911092

RESUMO

BACKGROUND: People after stroke often have postural impairments that can increase their risk of falling. Anticipatory postural adjustments (APAs) are changes in the activity of postural muscles prior to a voluntary movement in order to maintain vertical equilibrium. Previous research suggests that improving APAs leads to better postural control and reduces the risk of falls. Despite the importance of APAs and their impairment among people post-stroke, studies that aim to investigate methods for improving APAs are limited. Consistent evidence supports that an external focus of attention compared to an internal focus of attention, yields superior performance of motor skills that include postural control. RESEARCH QUESTION: What are the effects of adopting different foci of attention on measures of APAs and movement parameters when performing a lower extremity Fitts' task among people post-stroke? METHODS: Twelve individuals post-stroke performed a lower extremity stepping movement (Fitts' task) while adopting an external focus or an internal focus of attention in a within-subject design. A motion capture system was used to record participants' movement data. Custom software derived movement time (MT), peak velocity (PV), time to peak velocity (ttPV) and variability at endpoint (SDT). Electromyography was used to measure muscle activity and determine APAs onset and magnitude. For all dependent variables separate repeated measures ANOVAs were conducted to compare performance between foci of attention. RESULTS: The results showed that an external focus of attention yielded significantly better performance on all outcome measures. The improvement in performance was seen in shorter MT, higher PV, shorter ttPV, smaller SDT, earlier APAs onset and more efficient APAs magnitude. SIGNIFICANCE: The changes in outcome measures suggest that adopting an external focus of attention during postural tasks could be an effective strategy for improving balance control among people post-stroke.


Assuntos
Equilíbrio Postural/fisiologia , Acidente Vascular Cerebral/complicações , Atenção/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Acta Psychol (Amst) ; 207: 103086, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32422419

RESUMO

Rhythmic auditory stimuli (RAS) have been proposed to improve motor performance in populations with and without sensorimotor impairments. However, the reasons for the reported benefits are poorly understood. One idea is that RAS may supplement intrinsic feedback when other sensory input is diminished. The current experiment tested this idea by removing vision during a goal-directed reaching task. We hypothesized that any improvements in movement performance due to the RAS would be greater when vision was removed. Twenty-two typically developing adults performed reaching movements to one of two targets with RAS presented before movement initiation, after movement initiation, both before and after movement initiation, and no sound, all with and without vision. Dependent variables were analyzed using a 2 vision by 2 sound-before by 2 sound-during repeated measures ANOVA. Conditions where the metronome was heard before movement initiation yielded shorter and less variable reaction times compared when there was no sound before the movement. The RAS heard before and during the movement independently impacted spatial aspects of the movement. Sound before movement initiation resulted in smaller endpoint error, primarily in the anterior-posterior axis. Sound during the movement resulted in smaller endpoint error, primarily in the mediolateral axis. In no-vision blocks, inclusion of RAS resulted in improved endpoint performance, indicating that RAS supplemented the motor system. The present results strengthen our understanding of sensory integration underlying reaching performance by demonstrating that sound heard before and during a reaching movement can improve motor performance by supplementing the motor system when vision is unavailable.


Assuntos
Audição/fisiologia , Movimento/fisiologia , Desempenho Psicomotor , Adulto , Humanos , Tempo de Reação , Visão Ocular
18.
Somatosens Mot Res ; 37(2): 106-116, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32312126

RESUMO

Along with visual feedback, somatosensory feedback provides the nervous system with information regarding movement performance. Somatosensory system damage disrupts the normal feedback process, which can lead to a pins and needles sensation, or paresthaesia, and impaired movement control. The present study assessed the impact of temporarily induced median nerve paresthaesia, in individuals with otherwise intact sensorimotor function, on goal-directed reaching and grasping movements. Healthy, right-handed participants performed reach and grasp movements to five wooden Efron shapes, of which three were selected for analysis. Participants performed the task without online visual feedback and in two somatosensory conditions: 1) normal; and 2) disrupted somatosensory feedback. Disrupted somatosensory feedback was induced temporarily using a Digitimer (DS7AH) constant current stimulator. Participants' movements to shapes 15 or 30 cm to the right of the hand's start position were recorded using a 3 D motion analysis system at 300 Hz (Optotrak 3 D Investigator). Analyses revealed no significant differences for reaction time. Main effects for paresthaesia were observed for temporal and spatial aspects of the both the reach and grasp components of the movements. Although participants scaled their grip aperture to shape size under paresthaesia, the movements were smaller and more variable. Overall participants behaved as though they perceived they were performing larger and faster movements than they actually were. We suggest the presence of temporally induced paresthaesia affected online control by disrupting somatosensory feedback of the reach and grasp movements, ultimately leading to smaller forces and fewer corrective movements.


Assuntos
Retroalimentação Sensorial/fisiologia , Atividade Motora/fisiologia , Parestesia/fisiopatologia , Desempenho Psicomotor/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Estimulação Elétrica , Feminino , Objetivos , Humanos , Masculino , Nervo Mediano/fisiologia , Parestesia/complicações , Adulto Jovem
19.
Multisens Res ; 33(6): 599-623, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31899870

RESUMO

Multisensory integration is a fundamental form of sensory processing that is involved in many everyday tasks. Those with Attention-Deficit/Hyperactivity Disorder (ADHD) have characteristic alterations to various brain regions that may influence multisensory processing. The overall aim of this work was to assess how adults with ADHD process audiovisual multisensory stimuli during a complex response time task. The paradigm used was a two-alternative forced-choice discrimination task paired with continuous 64-electrode electroencephalography, allowing for the measurement of response time and accuracy to auditory, visual, and audiovisual multisensory conditions. Analysis revealed that those with ADHD ( n = 10) respond faster than neurotypical controls ( n = 12) when presented with auditory, visual, and audiovisual multisensory conditions, while also having race model violation in early response latency quantiles. Adults with ADHD also had more prominent multisensory processing over parietal-occipital brain regions at early post-stimulus latencies, indicating that altered brain structure may have important outcomes for audiovisual multisensory processing. The present study is the first to assess how those with ADHD respond to multisensory conditions during a complex response time task, and demonstrates that adults with ADHD have unique multisensory processing when assessing both behavioral response time measures and neurological measures.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Percepção Auditiva/fisiologia , Lobo Occipital/fisiopatologia , Lobo Parietal/fisiopatologia , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
20.
Front Psychol ; 10: 1564, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333557

RESUMO

Failure inherent to high-performance sport can precipitate emotional distress that can impair athletes' performance and physical and mental health. Identifying factors that allow athletes to manage failure to sustain their health is critical. Self-compassion, treating oneself kindly in response to failure, may help athletes manage failure; it buffers against negative affective psychological responses, yet athletes often fear self-compassion. It is unknown whether the benefits of self-compassion extend to athletes' physiological responses to failure and whether fear of self-compassion has an influence on psychological and physiological responses to failure, beyond self-compassion. The purpose of this study was to examine the influence of self-compassion on athletes' psychological and physiological responses when recalling a sport failure and determine if fear of self-compassion exerted unique effects, beyond self-compassion. Participants (n = 91; M age = 21) were university or national-level athletes. In this laboratory-based, observational study, athletes were connected to a multi-modal biofeedback system to measure physiological responding at baseline, during a stress induction (imagining a past performance failure), and during a recovery period. Physiological responding was assessed according to athletes' high-frequency heart rate variability (HRV), indexing parasympathetic nervous system activity, during the stress induction and recovery phase. Next, to assess psychological reactivity, athletes completed a series of scales (behavioral reactions, thoughts, and emotions). Regression analyses revealed that self-compassion predicted athletes' HRV reactivity to the stress induction (ß = 0.30, p < 0.05). There was no relationship between self-compassion and HRV recovery. Further, self-compassion predicted adaptive behavioral reactions (ß = 0.46, p < 0.01), and negatively predicted maladaptive thoughts (ß = -0.34, p < 0.01) and negative affect (ß = -0.39, p < 0.01). Fear of self-compassion explained additional variance in some maladaptive thoughts and behavioral reactions. Results suggest that self-compassion promotes adaptive physiological and psychological responses in athletes relative to a recalled sport failure and may have implications for performance enhancement, recovery and health outcomes. Further, addressing athletes' fears of self-compassion may also be important in promoting optimal psychological recovery.

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