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1.
Health Promot Pract ; : 15248399231221731, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38264858

RESUMO

People experiencing homelessness balance competing priorities resulting in reduced capacity to meet the care demands of chronic conditions, including Type 2 Diabetes Mellitus (T2DM). Arts-based performances present an avenue to expose others to these challenges. This article describes the process of incorporating qualitative research findings in a community-based participatory theater production to expose audiences to the day-to-day realities of living with T2DM while simultaneously experiencing homelessness. We conducted five focus groups and two individual interviews with people living with T2DM who had experienced homelessness with guidance from a community-engaged research team. We then collaborated with a local theater company to present common themes from these focus groups in a co-created play about the experience of managing T2DM while being homeless. We performed a staged reading of the play and assessed audience members' perceived stigma through a pre- and post-survey to determine if audience engagement within our theatrical production could reduce stigma toward individuals living with diabetes and/or people experiencing homelessness. This theatrical production is titled "Life Heist: Stealing Hope While Surviving Diabetes and Homelessness." Our work illustrates the feasibility and effectiveness of using participatory theater to disseminate qualitative research findings.

2.
Conscious Cogn ; 106: 103415, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36252519

RESUMO

The realism of body and actions in dreams is thought to be induced by simulations based on internal representations used during wakefulness. As somatosensory signals contribute to the updating of body and action representations, these are impaired when somatosensory signals are lacking. Here, we tested the hypothesis that individuals with somatosensory deafferentation have impaired body and actions in their dreams, as in wakefulness. We questioned three individuals with a severe, acquired sensory neuropathy on their dreams. While deafferented participants were impaired in daily life, they could dream of themselves as able-bodied, with some sensations (touch, proprioception) and actions (such as running or jumping) which had not been experienced in physical life since deafferentation. We speculate that simulation in dreams could be based on former, "healthy" body and action representations. Our findings are consistent with the idea that distinct body and action representations may be used during dreams and wakefulness.


Assuntos
Percepção do Tato , Vigília , Humanos , Sonhos , Tato , Propriocepção
3.
Exp Brain Res ; 239(7): 2043-2061, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33909112

RESUMO

Studies of chronically deafferented participants have illuminated how regaining some motor control after adult-onset loss of proprioceptive and touch input depends heavily on cognitive control. In this study we contrasted the performance of one such man, IW, with KS, a woman born without any somatosensory fibres. We postulated that her life-long absence of proprioception and touch might have allowed her to automate some simple visually-guided actions, something IW appears unable to achieve. We tested these two, and two age-matched control groups, on writing and drawing tasks performed with and without an audio-verbal echoing task that added a cognitive demand. In common with other studies of skilled action, the dual task was shown to affect visuo-motor performance in controls, with less well-controlled drawing and writing, evident as increases in path speed and reduction in curvature and trial duration. We found little evidence that IW was able to automate even the simplest drawing tasks and no evidence for automaticity in his writing. In contrast, KS showed a selective increase in speed of signature writing under the dual-task conditions, suggesting some ability to automate her most familiar writing. We also tested tracing of templates under mirror-reversed conditions, a task that imposes a powerful cognitive planning challenge. Both IW and KS showed evidence of a visuo-motor planning conflict, as did the controls, for shapes with sharp corners. Overall, IW was much faster than his controls to complete tracing shapes, consistent with an absence of visuo-proprioceptive conflict, whereas KS was slower than her controls, especially as the corners became sharper. She dramatically improved after a short period of practice while IW did not. We conclude that KS, who developed from birth without proprioception, may have some visually derived control of movement not under cognitive control, something not seen in IW. This allowed her to automate some writing and drawing actions, but impaired her initial attempts at mirror-tracing. In contrast, IW, who lost somatosensation as an adult, cannot automate these visually guided actions.


Assuntos
Propriocepção , Desempenho Psicomotor , Adulto , Feminino , Humanos , Masculino , Tato
4.
Exp Brain Res ; 239(4): 1203-1221, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33580292

RESUMO

The degree to which mental representations of the body can be established and maintained without somatosensory input remains unclear. We contrast two "deafferented" adults, one who acquired large fibre sensory loss as an adult (IW) and another who was born without somatosensation (KS). We compared their responses to those of matched controls in three perceptual tasks: first accuracy of their mental image of their hands (assessed by testing recognition of correct hand length/width ratio in distorted photographs and by locating landmarks on the unseen hand); then accuracy of arm length judgements (assessed by judgement of reaching distance), and finally, we tested for an attentional bias towards peri-personal space (assessed by reaction times to visual target presentation). We hypothesised that IW would demonstrate responses consistent with him accessing conscious knowledge, whereas KS might show evidence of responses dependent on non-conscious mechanisms. In the first two experiments, both participants were able to give consistent responses about hand shape and arm length, but IW displayed a better awareness of hand shape than KS (and controls). KS demonstrated poorer spatial accuracy in reporting hand landmarks than both IW and controls, and appears to have less awareness of her hands. Reach distance was overestimated by both IW and KS, as it was for controls; the precision of their judgements was slightly lower than that of the controls. In the attentional task, IW showed no reaction time differences across conditions in the visual detection task, unlike controls, suggesting that he has no peri-personal bias of attention. In contrast, KS did show target location-dependent modulation of reaction times, when her hands were visible. We suggest that both IW and KS can access a conscious body image, although its accuracy may reflect their different experience of hand action. Acquired sensory loss has deprived IW of any subconscious body awareness, but the congenital absence of somatosensation may have led to its partial replacement by a form of visual proprioception in KS.


Assuntos
Percepção do Tato , Tato , Adulto , Imagem Corporal , Feminino , Mãos , Humanos , Masculino , Propriocepção , Somatotipos , Percepção Espacial , Percepção Visual
5.
Proc Natl Acad Sci U S A ; 114(2): 352-357, 2017 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-28028234

RESUMO

Directional change in environmental drivers sometimes triggers regime shifts in ecosystems. Theory and experiments suggest that regime shifts can be detected in advance, and perhaps averted, by monitoring resilience indicators such as variance and autocorrelation of key ecosystem variables. However, it is uncertain whether management action prompted by a change in resilience indicators can prevent an impending regime shift. We caused a cyanobacterial bloom by gradually enriching an experimental lake while monitoring an unenriched reference lake and a continuously enriched reference lake. When resilience indicators exceeded preset boundaries, nutrient enrichment was stopped in the experimental lake. Concentrations of algal pigments, dissolved oxygen saturation, and pH rapidly declined following cessation of nutrient enrichment and became similar to the unenriched lake, whereas a large bloom occurred in the continuously enriched lake. This outcome suggests that resilience indicators may be useful in management to prevent unwanted regime shifts, at least in some situations. Nonetheless, a safer approach to ecosystem management would build and maintain the resilience of desirable ecosystem conditions, for example, by preventing excessive nutrient input to lakes and reservoirs.


Assuntos
Cianobactérias/fisiologia , Eutrofização/fisiologia , Ecossistema , Monitoramento Ambiental/métodos , Lagos/microbiologia , Modelos Biológicos
6.
Exp Brain Res ; 237(9): 2167-2184, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31209510

RESUMO

Previous work has highlighted the role of haptic feedback for manual dexterity, in particular for the control of precision grip forces between the index finger and thumb. It is unclear how fine motor skills involving more than just two digits might be affected, especially given that loss of sensation from the hand affects many neurological patients, and impacts on everyday actions. To assess the functional consequences of haptic deficits on multi-digit grasp of objects, we studied the ability of three rare individuals with permanent large-fibre sensory loss involving the entire upper limb. All three reported difficulties in everyday manual actions (ABILHAND questionnaire). Their performance in a reach-grasp-lift task was compared to that of healthy controls. Twenty objects of varying shape, mass, opacity and compliance were used. In the reach-to-grasp phase, we found slower movement, larger grip aperture and less dynamic modulation of grip aperture in deafferented participants compared to controls. Hand posture during the lift phase also differed; deafferented participants often adopted hand postures that may have facilitated visual guidance, and/or reduced control complexity. For example, they would extend fingers that were not in contact with the object, or fold these fingers into the palm of the hand. Variability in hand postures was increased in deafferented participants, particularly for smaller objects. Our findings provide new insights into how the complex control required for whole hand actions is compromised by loss of haptic feedback, whose contribution is, thus, highlighted.


Assuntos
Retroalimentação Sensorial/fisiologia , Mãos/fisiopatologia , Destreza Motora/fisiologia , Postura/fisiologia , Propriocepção/fisiologia , Transtornos de Sensação/fisiopatologia , Percepção do Tato/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Eur J Vasc Endovasc Surg ; 55(2): 281-287, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29310896

RESUMO

OBJECTIVES: Radiation protection training courses currently focus on broad knowledge topics which may not always be relevant in daily practice. The goal of this study was to determine the key competencies in radiation protection that every endovascular team member should possess and apply routinely, through multispecialty clinical content expert consensus. METHODS: Consensus was obtained through a two round modified Delphi methodology. The expert panel consisted of European vascular surgeons, interventional radiologists, and interventional cardiologists/angiologists experienced in endovascular procedures. An initial list of statements, covering knowledge skills, technical skills and attitudes was created, based on a literature search. Additional statements could be suggested by the experts in the first Delphi round. Each of the statements had to be rated on a 5- point Likert scale. A statement was considered to be a key competency when the internal consistency was greater than alpha = 0.80 and at least 80% of the experts agreed (rating 4/5) or strongly agreed (rating 5/5) with the statement. Questionnaires were emailed to panel members using the Surveymonkey service. RESULTS: Forty-one of 65 (63.1%) invited experts agreed to participate in the study. The response rates were 36 out of 41 (87.8%): overall 38 out of 41(92.6%) in the first round and 36 out of 38 (94.7%) in the second round. The 71 primary statements were supplemented with nine items suggested by the panel. The results showed excellent consensus among responders (Cronbach's alpha = 0.937 first round; 0.958 s round). Experts achieved a consensus that 30 of 33 knowledge skills (90.9%), 23 of 27 technical skills (82.1%), and 15 of 20 attitudes (75.0%) should be considered as key competencies. CONCLUSIONS: A multispecialty European endovascular expert panel reached consensus about the key competencies in radiation protection. These results may serve to create practical and relevant radiation protection training courses in the future, enhancing radiation safety for both patients and the entire endovascular team.


Assuntos
Competência Clínica , Consenso , Procedimentos Endovasculares/efeitos adversos , Proteção Radiológica , Adulto , Atitude do Pessoal de Saúde , Cardiologistas/psicologia , Técnica Delphi , Correio Eletrônico , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiologistas/psicologia , Cirurgiões/psicologia , Inquéritos e Questionários , Raios X/efeitos adversos
8.
Exp Brain Res ; 236(8): 2137-2155, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29779050

RESUMO

It is uncertain how vision and proprioception contribute to adaptation of voluntary arm movements. In normal participants, adaptation to imposed forces is possible with or without vision, suggesting that proprioception is sufficient; in participants with proprioceptive loss (PL), adaptation is possible with visual feedback, suggesting that proprioception is unnecessary. In experiment 1 adaptation to, and retention of, perturbing forces were evaluated in three chronically deafferented participants. They made rapid reaching movements to move a cursor toward a visual target, and a planar robot arm applied orthogonal velocity-dependent forces. Trial-by-trial error correction was observed in all participants. Such adaptation has been characterized with a dual-rate model: a fast process that learns quickly, but retains poorly and a slow process that learns slowly and retains well. Experiment 2 showed that the PL participants had large individual differences in learning and retention rates compared to normal controls. Experiment 3 tested participants' perception of applied forces. With visual feedback, the PL participants could report the perturbation's direction as well as controls; without visual feedback, thresholds were elevated. Experiment 4 showed, in healthy participants, that force direction could be estimated from head motion, at levels close to the no-vision threshold for the PL participants. Our results show that proprioceptive loss influences perception, motor control and adaptation but that proprioception from the moving limb is not essential for adaptation to, or detection of, force fields. The differences in learning and retention seen between the three deafferented participants suggest that they achieve these tasks in idiosyncratic ways after proprioceptive loss, possibly integrating visual and vestibular information with individual cognitive strategies.


Assuntos
Braço/fisiopatologia , Aprendizagem/fisiologia , Movimento/fisiologia , Doenças do Sistema Nervoso Periférico/complicações , Propriocepção/fisiologia , Transtornos de Sensação/etiologia , Adaptação Fisiológica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Visão Ocular , Percepção Visual/fisiologia
9.
J Appl Biomech ; 33(1): 56-63, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27735232

RESUMO

Running during sports and for physical activity often requires changes in velocity through acceleration and deceleration. While it is clear that lower extremity biomechanics vary during these accelerations and decelerations, the work requirements of the individual joints are not well understood. The purpose of this investigation was to measure the sagittal plane mechanical work of the individual lower extremity joints during acceleration, deceleration, and steady-state running. Ten runners were compared during acceleration, deceleration, and steady-state running using three-dimensional kinematics and kinetics measures. Total positive and negative joint work, and relative joint contributions to total work were compared between conditions. Total positive work progressively increased from deceleration to acceleration. This was due to greater ankle joint work during acceleration. While there was no significant change in total negative work during deceleration, there was a greater relative contribution of the knee to total negative work with a subsequent lower relative ankle negative work. Each lower extremity joint exhibits distinct functional roles in acceleration compared with deceleration during level running. Deceleration is dominated by greater contributions of the knee to negative work while acceleration is associated with a greater ankle contribution to positive work.


Assuntos
Aceleração , Articulação do Tornozelo/fisiologia , Transferência de Energia/fisiologia , Articulação do Quadril/fisiologia , Articulação do Joelho/fisiologia , Esforço Físico/fisiologia , Corrida/fisiologia , Simulação por Computador , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Modelos Biológicos , Adulto Jovem
10.
Ecol Lett ; 19(3): 230-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26689608

RESUMO

Terrestrial organic matter can be assimilated by aquatic consumers but implications for biomass and production are unresolved. An ecosystem model was fit to estimate effects of phosphorus (P) load, planktivory, and supply rate of terrestrial particulate organic carbon (TPOC) on phytoplankton and zooplankton in five whole-lake experiments. Phytoplankton biomass increased with P load and planktivory and decreased with TPOC supply rate. Zooplankton biomass increased with P load and responded weakly to planktivory and TPOC supply rate. Zooplankton allochthony (proportion of carbon from terrestrial sources) decreased with P load and planktivory and increased with TPOC supply rate. Lakes with low allochthony (< 0.3) had wide ranges of phytoplankton and zooplankton biomass and production, depending on P load and planktivory. Lakes with high allochthony (> 0.3) had low biomass and production of both phytoplankton and zooplankton. In summary, terrestrial OC inhibits primary production and is a relatively low-quality food source for zooplankton.


Assuntos
Biomassa , Carbono/análise , Cadeia Alimentar , Modelos Biológicos , Fósforo/metabolismo , Plâncton/crescimento & desenvolvimento , Lagos/química
11.
J Neurophysiol ; 115(4): 1946-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26843597

RESUMO

When lifting novel objects, individuals' fingertip forces are influenced by a variety of cues such as volume and apparent material. This means that heavy-looking objects tend to be lifted with more force than lighter-looking objects, even when they weigh the same amount as one another. Expectations about object weight based on visual appearance also influence how heavy an object feels when it is lifted. For instance, in the "size-weight illusion," small objects feel heavier than equally weighted large objects. Similarly, in the "material-weight illusion," objects that seem to be made from light-looking materials feel heavier than objects of the same weight that appear to be made from heavy-looking materials. In this study, we investigated these perceptual and sensorimotor effects in IW, an individual with peripheral deafferentation (i.e., a loss of tactile and proprioception feedback). We examined his perceptions of heaviness and fingertip force application over repeated lifts of objects that varied in size or material properties. Despite being able to report real weight differences, IW did not appear to experience the size- or material-weight illusions. Furthermore, he showed no evidence of sensorimotor prediction based on size and material cues. The results are discussed in the context of forward models and their possible influence on weight perception and fingertip force control.


Assuntos
Ilusões , Distúrbios Somatossensoriais/fisiopatologia , Percepção de Peso , Estudos de Casos e Controles , Retroalimentação Sensorial , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/fisiologia , Neurônios Aferentes/patologia , Neurônios Aferentes/fisiologia , Percepção do Tato
12.
Proc Natl Acad Sci U S A ; 110(43): 17398-403, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24101479

RESUMO

Environmental sensor networks are developing rapidly to assess changes in ecosystems and their services. Some ecosystem changes involve thresholds, and theory suggests that statistical indicators of changing resilience can be detected near thresholds. We examined the capacity of environmental sensors to assess resilience during an experimentally induced transition in a whole-lake manipulation. A trophic cascade was induced in a planktivore-dominated lake by slowly adding piscivorous bass, whereas a nearby bass-dominated lake remained unmanipulated and served as a reference ecosystem during the 4-y experiment. In both the manipulated and reference lakes, automated sensors were used to measure variables related to ecosystem metabolism (dissolved oxygen, pH, and chlorophyll-a concentration) and to estimate gross primary production, respiration, and net ecosystem production. Thresholds were detected in some automated measurements more than a year before the completion of the transition to piscivore dominance. Directly measured variables (dissolved oxygen, pH, and chlorophyll-a concentration) related to ecosystem metabolism were better indicators of the approaching threshold than were the estimates of rates (gross primary production, respiration, and net ecosystem production); this difference was likely a result of the larger uncertainties in the derived rate estimates. Thus, relatively simple characteristics of ecosystems that were observed directly by the sensors were superior indicators of changing resilience. Models linked to thresholds in variables that are directly observed by sensor networks may provide unique opportunities for evaluating resilience in complex ecosystems.


Assuntos
Bass/crescimento & desenvolvimento , Ecossistema , Peixes/crescimento & desenvolvimento , Lagos , Zooplâncton/crescimento & desenvolvimento , Algoritmos , Animais , Biomassa , Clorofila/metabolismo , Clorofila A , Monitorização de Parâmetros Ecológicos/métodos , Peixes/classificação , Concentração de Íons de Hidrogênio , Modelos Biológicos , Oxigênio/metabolismo , Dinâmica Populacional , Fatores de Tempo , Zooplâncton/classificação
13.
J Neurophysiol ; 114(5): 2764-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26334018

RESUMO

Humans can remarkably adapt their motor behavior to novel environmental conditions, yet it remains unclear which factors enable us to transfer what we have learned with one limb to the other. Here we tested the hypothesis that interlimb transfer of sensorimotor adaptation is determined by environmental conditions but also by individual characteristics. We specifically examined the adaptation of unconstrained reaching movements to a novel Coriolis, velocity-dependent force field. Right-handed subjects sat at the center of a rotating platform and performed forward reaching movements with the upper limb toward flashed visual targets in prerotation, per-rotation (i.e., adaptation), and postrotation tests. Here only the dominant arm was used during adaptation and interlimb transfer was assessed by comparing performance of the nondominant arm before and after dominant-arm adaptation. Vision and no-vision conditions did not significantly influence interlimb transfer of trajectory adaptation, which on average was significant but limited. We uncovered a substantial heterogeneity of interlimb transfer across subjects and found that interlimb transfer can be qualitatively and quantitatively predicted for each healthy young individual. A classifier showed that in our study, interlimb transfer could be predicted based on the subject's task performance, most notably motor variability during learning, and his or her laterality quotient. Positive correlations suggested that variability of motor performance and lateralization of arm movement control facilitate interlimb transfer. We further show that these individual characteristics can predict the presence and the magnitude of interlimb transfer of left-handers. Overall, this study suggests that individual characteristics shape the way the nervous system can generalize motor learning.


Assuntos
Adaptação Fisiológica , Desempenho Psicomotor , Transferência de Experiência/fisiologia , Adulto , Fenômenos Biomecânicos , Retroalimentação Sensorial , Feminino , Humanos , Masculino , Propriocepção , Extremidade Superior/fisiologia , Adulto Jovem
14.
Ann Neurol ; 75(6): 917-24, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24816757

RESUMO

OBJECTIVE: Tactile spatial acuity is routinely tested in neurology to assess the state of the dorsal column system. In contrast, spatial acuity for pain is not assessed, having never been systematically characterized. More than a century after the initial description of tactile acuity across the body, we provide the first systematic whole-body mapping of spatial acuity for pain. METHODS: We evaluated the 2-point discrimination thresholds for both nociceptive-selective and tactile stimuli across several skin regions. Thresholds were estimated using pairs of simultaneous stimuli, and also using successive stimuli. RESULTS AND INTERPRETATION: These two approaches produced convergent results. The fingertip was the area of highest spatial acuity, for both pain and touch. On the glabrous skin of the hand, the gradient of spatial acuity for pain followed that observed for touch. On the hairy skin of the upper limb, spatial acuity for pain and touch followed opposite proximal-distal gradients, consistent with the known innervation density of this body territory. Finally, by testing spatial acuity for pain in a rare participant completely lacking Aß fibers, we demonstrate that spatial acuity for pain does not rely on a functioning system of tactile primary afferents. This study represents the first systematic characterization of spatial acuity for pain across multiple regions of the body surface.


Assuntos
Discriminação Psicológica , Dor/patologia , Dor/fisiopatologia , Limiar Sensorial/fisiologia , Percepção Espacial/fisiologia , Tato/fisiologia , Adulto , Feminino , Dedos/inervação , Testa/inervação , Humanos , Masculino , Estimulação Física , Pele/inervação , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 108(5): 1975-80, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21245299

RESUMO

Cross-ecosystem subsidies to food webs can alter metabolic balances in the receiving (subsidized) system and free the food web, or particular consumers, from the energetic constraints of local primary production. Although cross-ecosystem subsidies between terrestrial and aquatic systems have been well recognized for benthic organisms in streams, rivers, and the littoral zones of lakes, terrestrial subsidies to pelagic consumers are more difficult to demonstrate and remain controversial. Here, we adopt a unique approach by using stable isotopes of H, C, and N to estimate terrestrial support to zooplankton in two contrasting lakes. Zooplankton (Holopedium, Daphnia, and Leptodiaptomus) are comprised of ≈ 20-40% of organic material of terrestrial origin. These estimates are as high as, or higher than, prior measures obtained by experimentally manipulating the inorganic (13)C content of these lakes to augment the small, natural contrast in (13)C between terrestrial and algal photosynthesis. Our study gives credence to a growing literature, which we review here, suggesting that significant terrestrial support of pelagic crustaceans (zooplankton) is widespread.


Assuntos
Carbono/metabolismo , Água Doce , Hidrogênio/metabolismo , Nitrogênio/metabolismo , Zooplâncton/metabolismo , Animais , Isótopos , Especificidade da Espécie
16.
Clin Neurophysiol Pract ; 9: 39-50, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38274859

RESUMO

Though a common symptom, fatigue is difficult to define and investigate, occurs in a wide variety of neurological and systemic disorders, with differing pathological causes. It is also often accompanied by a psychological component. As a symptom of long-term COVID-19 it has gained more attention. In this review, we begin by differentiating fatigue, a perception, from fatigability, quantifiable through biomarkers. Central and peripheral nervous system and muscle disorders associated with these are summarised. We provide a comprehensive and objective framework to help identify potential causes of fatigue and fatigability in a given disease condition. It also considers the effectiveness of neurophysiological tests as objective biomarkers for its assessment. Among these, twitch interpolation, motor cortex stimulation, electroencephalography and magnetencephalography, and readiness potentials will be described for the assessment of central fatigability, and surface and needle electromyography (EMG), single fibre EMG and nerve conduction studies for the assessment of peripheral fatigability. The purpose of this review is to guide clinicians in how to approach fatigue, and fatigability, and to suggest that neurophysiological tests may allow an understanding of their origin and interactions. In this way, their differing types and origins, and hence their possible differing treatments, may also be defined more clearly.

17.
Clin Neurophysiol ; 163: 255-262, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704307

RESUMO

One hundred years ago, Erlanger and Gasser demonstrated that conduction velocity is correlated with the diameter of a peripheral nerve axon. Later, they also demonstrated that the functional role of the axon is related to its diameter: touch is signalled by large-diameter axons, whereas pain and temperature are signalled by small-diameter axons. Certain discoveries in recent decades prompt a modification of this canonical classification. Here, we review the evidence for unmyelinated (C) fibres signalling touch at a slow conduction velocity and likely contributing to affective aspects of tactile information. We also review the evidence for large-diameter Aß afferents signalling pain at ultrafast conduction velocity and likely contributing to the rapid nociceptive withdrawal reflex. These discoveries imply that conduction velocity is not as clear-cut an indication of the functional role of the axon as previously thought. We finally suggest that a future taxonomy of the peripheral afferent nervous system might be based on the combination of the axons molecular expression and electrophysiological response properties.


Assuntos
Condução Nervosa , Nervos Periféricos , Humanos , Animais , Nervos Periféricos/fisiopatologia , Nervos Periféricos/fisiologia , Condução Nervosa/fisiologia , Tato/fisiologia , Dor/fisiopatologia , Dor/classificação , Fibras Nervosas Amielínicas/fisiologia , Axônios/fisiologia
18.
bioRxiv ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36711691

RESUMO

Implicit sensorimotor adaptation keeps our movements well-calibrated amid changes in the body and environment. We have recently postulated that implicit adaptation is driven by a perceptual error: the difference between the desired and perceived movement outcome. According to this perceptual re-alignment model, implicit adaptation ceases when the perceived movement outcome - a multimodal percept determined by a prior belief conveying the intended action, the motor command, and feedback from proprioception and vision - is aligned with the desired movement outcome. Here, we examined the role of proprioception in implicit motor adaptation and perceived movement outcome by examining individuals who lack proprioception. We used a modified visuomotor rotation task designed to isolate implicit adaptation and probe perceived outcome throughout the experiment. Surprisingly, implicit adaptation and perceived outcome were minimally impacted by deafferentation, posing a challenge to the perceptual re-alignment model of implicit adaptation.

19.
Behav Brain Sci ; 36(4): 421-2, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23883750

RESUMO

The notion of an enactive system requires thinking about the brain in a way that is different from the standard computational-representational models. In evolutionary terms, the brain does what it does and is the way that it is, across some scale of variations, because it is part of a living body with hands that can reach and grasp in certain limited ways, eyes structured to focus, an autonomic system, an upright posture, etc. coping with specific kinds of environments, and with other people. Changes to any of the bodily, environmental, or intersubjective conditions elicit responses from the system as a whole. On this view, rather than representing or computing information, the brain is better conceived as participating in the action.


Assuntos
Cognição/fisiologia , Relações Interpessoais , Neurônios-Espelho/fisiologia , Percepção Social , Teoria da Mente/fisiologia , Humanos
20.
Clin Neurophysiol ; 156: 76-85, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37897906

RESUMO

There are significant differences in duration and intensity of clinical neurophysiology specialty training within the countries of the Europe, Middle East and Africa Chapter of the International Federation of Clinical Neurophysiology. We address these differences by proposing recommendations which may facilitate harmonisation of training and education within the Chapter. They arose from two workshops whose recommendations were then circulated widely within national societies in the Chapter for feedback and for consensus. The recommendations are applicable to clinical neurophysiology as a medical monospecialty and/or as a subspecialty (usually of neurology). We make a number of recommendations on governance and regulation of training, on the requirements for competence and the numbers of various examinations and tests performed by trainees, some under supervision. We also recommend a modular approach considering primary and complementary modules. Primary modules are electroencephalography, electromyography, nerve conduction studies and evoked potentials, while complementary ones include sleep analysis, intraoperative monitoring, small fibre testing, peripheral nerve and muscle ultrasound, intracortical recordings, and analysis of movement disorders. It is recommended that national examinations should include a variety of techniques to assess knowledge and judgement, practical skills, teamwork, communication skills, as well as safety and quality. The aim of the suggested recommendations is to harmonize clinical neurophysiology training in the member societies throughout the Chapter. It is realised that this may mean that the numbers for competence are aspirational for some, though ways to mitigate this, for instance through supranational training centres, are also discussed.


Assuntos
Eletroencefalografia , Neurofisiologia , Humanos , Neurofisiologia/métodos , Europa (Continente) , Oriente Médio , África
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