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1.
PLoS One ; 15(3): e0229270, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134950

RESUMO

Despite a growing body of research on perinatal sensory abilities, data on the extent of tactile sensitivity and more particularly passive touch (i.e. sensitivity to a stimulation imposed on the skin) are relatively limited, and the development and processing of tactile function are still thus little known. This question is particularly of high importance for infants with atypical early development such as those born prematurely who are exposed to many sensory (including tactile) stimulations (being in a hospital setting) during a critical period of brain development and those born at early term whose birth occurs at the precise time of cortical reorganization, in particular in the sensory areas. Some parents and health-care providers have for instance reported that children born prematurely exhibit atypical (e.g. higher) sensitivity to "benign" tactile stimuli. In the present study, we hypothesized that preterm and early-term infants may show altered tactile sensitivity. We compared the behavioral responses around term-equivalent age of infants born either pre-term, early-term or at term to the application of a light (0.008 grams) mechanical stimulus. We found that almost all preterm infants perceive this tactile stimulus, contrarily to the two other groups of infants. This extreme tactile sensitivity may be due to experiential, maturational or more likely both processes. We also compared the tactile sensitivity of these infants to that of adults. We found that adults were irresponsive to the light mechanical stimulus. This finding opens not only new insights in understanding development of tactile processing, but also new lines of thought about the particular sensory world of premature and early-term infants and hence about the potential impact of early care practices.


Assuntos
Recém-Nascido Prematuro/fisiologia , Percepção do Tato/fisiologia , Adulto , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Estimulação Luminosa , Projetos Piloto
2.
Science ; 367(6480): 910-912, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32079771

RESUMO

Many animals can associate object shapes with incentives. However, such behavior is possible without storing images of shapes in memory that are accessible to more than one sensory modality. One way to explore whether there are modality-independent internal representations of object shapes is to investigate cross-modal recognition-experiencing an object in one sensory modality and later recognizing it in another. We show that bumble bees trained to discriminate two differently shaped objects (cubes and spheres) using only touch (in darkness) or vision (in light, but barred from touching the objects) could subsequently discriminate those same objects using only the other sensory information. Our experiments demonstrate that bumble bees possess the ability to integrate sensory information in a way that requires modality-independent internal representations.


Assuntos
Abelhas/fisiologia , Reconhecimento Fisiológico de Modelo , Reconhecimento Visual de Modelos , Percepção do Tato , Animais , Escuridão
3.
Sci Rep ; 10(1): 1357, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992799

RESUMO

Haptic interface technologies for virtual reality applica have been developed to increase the reality and manipulability of a virtual object by creating a diverse tactile sensation. Most evaluation of the haptic technologies, however, have been limited to the haptic perception of the tactile stimuli via static virtual objects. Noting this, we investigated the effect of lateral cutaneous feedback, along with kinesthetic feedback on the perception of virtual object weight during manipulation. We modeled the physical interaction between a participant's finger avatars and virtual objects. The haptic stimuli were rendered with custom-built haptic feedback systems that can provide kinesthetic and lateral cutaneous feedback to the participant. We conducted two virtual object manipulation experiments, 1. a virtual object manipulation with one finger, and 2. the pull-out and lift-up of a virtual object grasped with a precision grip. The results of Experiment 1 indicate that the participants felt the virtual object rendered with lateral cutaneous feedback significantly heavier than with only kinesthetic feedback (p < 0.05 for mref = 100 and 200 g). Similarly, the participants of Experiment 2 felt the virtual objects significantly heavier when lateral cutaneous feedback was available (p < 0.05 for mref = 100, 200, and 300 g). Therefore, the additional lateral cutaneous feedback to the force feedback led the participants to feel the virtual object heavier than without the cutaneous feedback. The results also indicate that the contact force applied to a virtual object during manipulation can be a function of the perceived object weight p = 0.005 for Experiment 1 and p = 0.2 for Experiment 2.


Assuntos
Dedos , Percepção do Tato , Realidade Virtual , Percepção Visual , Percepção de Peso , Adulto , Retroalimentação , Feminino , Humanos , Masculino , Pele
4.
PLoS One ; 15(1): e0226880, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31896135

RESUMO

Haptic exploration is a key skill for both robots and humans to discriminate and handle unknown objects or to recognize familiar objects. Its active nature is evident in humans who from early on reliably acquire sophisticated sensory-motor capabilities for active exploratory touch and directed manual exploration that associates surfaces and object properties with their spatial locations. This is in stark contrast to robotics. In this field, the relative lack of good real-world interaction models-along with very restricted sensors and a scarcity of suitable training data to leverage machine learning methods-has so far rendered haptic exploration a largely underdeveloped skill. In robot vision however, deep learning approaches and an abundance of available training data have triggered huge advances. In the present work, we connect recent advances in recurrent models of visual attention with previous insights about the organisation of human haptic search behavior, exploratory procedures and haptic glances for a novel architecture that learns a generative model of haptic exploration in a simulated three-dimensional environment. This environment contains a set of rigid static objects representing a selection of one-dimensional local shape features embedded in a 3D space: an edge, a flat and a convex surface. The proposed algorithm simultaneously optimizes main perception-action loop components: feature extraction, integration of features over time, and the control strategy, while continuously acquiring data online. Inspired by the Recurrent Attention Model, we formalize the target task of haptic object identification in a reinforcement learning framework and reward the learner in the case of success only. We perform a multi-module neural network training, including a feature extractor and a recurrent neural network module aiding pose control for storing and combining sequential sensory data. The resulting haptic meta-controller for the rigid 16 × 16 tactile sensor array moving in a physics-driven simulation environment, called the Haptic Attention Model, performs a sequence of haptic glances, and outputs corresponding force measurements. The resulting method has been successfully tested with four different objects. It achieved results close to 100% while performing object contour exploration that has been optimized for its own sensor morphology.


Assuntos
Robótica/instrumentação , Tato , Algoritmos , Simulação por Computador , Aprendizado Profundo , Percepção de Forma , Humanos , Aprendizagem , Modelos Teóricos , Redes Neurais de Computação , Percepção do Tato
5.
Neuron ; 105(1): 16-33, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31917952

RESUMO

Many brain areas modulate their activity during vibrotactile tasks. The activity from these areas may code the stimulus parameters, stimulus perception, or perceptual reports. Here, we discuss findings obtained in behaving monkeys aimed to understand these processes. In brief, neurons from the somatosensory thalamus and primary somatosensory cortex (S1) only code the stimulus parameters during the stimulation periods. In contrast, areas downstream of S1 code the stimulus parameters during not only the task components but also perception. Surprisingly, the midbrain dopamine system is an actor not considered before in perception. We discuss the evidence that it codes the subjective magnitude of a sensory percept. The findings reviewed here may help us to understand where and how sensation transforms into perception in the brain.


Assuntos
Neurônios Dopaminérgicos/fisiologia , Mesencéfalo/fisiologia , Córtex Somatossensorial/fisiologia , Tálamo/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Animais
6.
Nat Commun ; 11(1): 268, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937777

RESUMO

A bionic artificial device commonly integrates various distributed functional units to mimic the functions of biological sensory neural system, bringing intricate interconnections, complicated structure, and interference in signal transmission. Here we show an all-in-one bionic artificial nerve based on a separate electrical double-layers structure that integrates the functions of perception, recognition, and transmission. The bionic artificial nerve features flexibility, rapid response (<21 ms), high robustness, excellent durability (>10,000 tests), personalized cutability, and no energy consumption when no mechanical stimulation is being applied. The response signals are highly regionally differentiated for the mechanical stimulations, which enables the bionic artificial nerve to mimic the spatiotemporally dynamic logic of a biological neural network. Multifunctional touch interactions demonstrate the enormous potential of the bionic artificial nerve for human-machine hybrid perceptual enhancement. By incorporating the spatiotemporal resolution function and algorithmic analysis, we hope that bionic artificial nerves will promote further development of sophisticated neuroprosthetics and intelligent robotics.


Assuntos
Inteligência Artificial , Materiais Biomiméticos , Biônica , Fibras Nervosas/fisiologia , Algoritmos , Técnicas Biossensoriais , Humanos , Redes Neurais de Computação , Robótica , Tato , Percepção do Tato
7.
Am J Psychiatry ; 177(1): 37-46, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416339

RESUMO

OBJECTIVE: Childhood maltreatment is a major risk factor for psychopathology associated with interpersonal problems in adulthood, but the etiological pathways involved are still unclear. The authors propose that childhood maltreatment confers risk for dysfunctional behavior in social interactions by altering interpersonal distance preference and the processing of social touch. METHODS: Ninety-two medication-free adults (64 of them female) with low, medium, and high levels of childhood maltreatment were tested with an interpersonal distance paradigm and subsequently underwent a social touch functional MRI task during which they rated the perceived comfort of slow touch (C-tactile [CT] optimal speed; 5 cm/s) and fast touch (non-CT-optimal speed; 20 cm/s). RESULTS: Participants with high childhood maltreatment levels preferred a larger interpersonal distance and experienced fast touch as less comforting compared with participants with no or moderate childhood maltreatment experiences. On the neural level, participants with severe childhood maltreatment exhibited exaggerated responses to fast touch in the right somatosensory and posterior insular cortex, which correlated with lower comfort ratings. Severe childhood maltreatment was associated with decreased activation in the right hippocampus in response to slow touch. This response pattern was not moderated or mediated by childhood maltreatment-associated region-specific reductions in gray matter volume. CONCLUSIONS: The study findings suggest that higher childhood maltreatment levels are associated with hypersensitivity characterized by a preference for larger interpersonal distance and discomfort of fast touch. These dysregulations were manifested in a sensory cortical hyperreactivity and limbic CT-related hypoactivation. These results may shed light on why individuals with severe childhood maltreatment exhibit an increased susceptibility to interpersonal dysfunctions and psychiatric disorders in adulthood.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Córtex Cerebral/fisiopatologia , Hipocampo/fisiopatologia , Relações Interpessoais , Distância Social , Córtex Somatossensorial/fisiopatologia , Adulto , Atrofia/patologia , Feminino , Neuroimagem Funcional , Substância Cinzenta/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Percepção do Tato/fisiologia , Adulto Jovem
8.
J Sports Med Phys Fitness ; 60(1): 17-25, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31640309

RESUMO

BACKGROUND: Practicing competitive sports, particularly those disciplines in which the upper limbs are involved in the movement, develops physical fitness and its special feature, namely the hand-eye coordination. Some sport disciplines require manipulation of an object. Using a sport equipment every day, several times, during training and matches must affect the characteristics of the skin of the palmar side of the hand. It may be presumed to affect the tactile sensitivity of the skin. The aim of the study was to determine the relationship between hand-eye coordination and tactile sensitivity in basketball, volleyball, handball, football and combat sports players as compared to those who do not practice competitive sports. METHODS: Overall, 121 men were subject to tests. The tactile sensitivity threshold was determined at three points of the palmar side of the hand using The Touch-Test™ Sensory Evaluators esthesiometer. The second test involved hand-eye coordination of the upper limbs and it was carried out using cross-type machine. RESULTS: The greatest tactile sensitivity was shown in combat sports players. These players also demonstrated the shortest reaction time and the lowest number of errors in the motor coordination test. The correlation between tactile sensitivity and coordination was found to be the strongest in subjects not practicing sports. CONCLUSIONS: The most interesting finding is that in the group of athletes using hands (team sports games and combat sports) the correlation between movement coordination and tactile sensitivity is weaker.


Assuntos
Tempo de Reação/fisiologia , Esportes/fisiologia , Percepção do Tato/fisiologia , Adulto , Estudos de Casos e Controles , Humanos , Masculino , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem
9.
J Autism Dev Disord ; 50(1): 87-100, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31538259

RESUMO

Although impairment in sensory integration is suggested in the autism spectrum (AS), empirical evidences remain equivocal. We assessed the integration of low-level visual and tactile information within and across modalities in AS and typically developing (TD) individuals. TD individuals demonstrated increased redundancy gain for cross-modal relative to double tactile or visual stimulation, while AS individuals showed similar redundancy gain between cross-modal and double tactile conditions. We further observed that violation of the race model inequality for cross-modal conditions was observed over a wider proportion of the reaction times distribution in TD than AS individuals. Importantly, the reduced cross-modal integration in AS individuals was not related to atypical attentional shift between modalities. We conclude that AS individuals displays selective decrease of cross-modal integration of low-level information.


Assuntos
Transtorno Autístico/fisiopatologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Atenção , Transtornos Globais do Desenvolvimento Infantil , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Tato/fisiologia
10.
Proc Natl Acad Sci U S A ; 117(2): 1191-1200, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31879342

RESUMO

Intracortical microstimulation (ICMS) of the somatosensory cortex evokes vivid tactile sensations and can be used to convey sensory feedback from brain-controlled bionic hands. Changes in ICMS frequency lead to changes in the resulting sensation, but the discriminability of frequency has only been investigated over a narrow range of low frequencies. Furthermore, the sensory correlates of changes in ICMS frequency remain poorly understood. Specifically, it remains to be elucidated whether changes in frequency only modulate sensation magnitude-as do changes in amplitude-or whether they also modulate the quality of the sensation. To fill these gaps, we trained monkeys to discriminate the frequency of ICMS pulse trains over a wide range of frequencies (from 10 to 400 Hz). ICMS amplitude also varied across stimuli to dissociate sensation magnitude from ICMS frequency and ensure that animals could not make frequency judgments based on magnitude. We found that animals could consistently discriminate ICMS frequency up to ∼200 Hz but that the sensory correlates of frequency were highly electrode dependent: On some electrodes, changes in frequency were perceptually distinguishable from changes in amplitude-seemingly giving rise to a change in sensory quality; on others, they were not. We discuss the implications of our findings for neural coding and for brain-controlled bionic hands.


Assuntos
Estimulação Elétrica/métodos , Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Animais , Escala de Avaliação Comportamental , Eletrodos Implantados , Retroalimentação Sensorial , Macaca mulatta , Masculino
11.
Elife ; 82019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31872799

RESUMO

C-tactile afferents form a distinct channel that encodes pleasant tactile stimulation. Prevailing views indicate they project, as with other unmyelinated afferents, in lamina I-spinothalamic pathways. However, we found that spinothalamic ablation in humans, whilst profoundly impairing pain, temperature and itch, had no effect on pleasant touch perception. Only discriminative touch deficits were seen. These findings preclude privileged C-tactile-lamina I-spinothalamic projections and imply integrated hedonic and discriminative spinal processing from the body.


Assuntos
Princípio do Prazer-Desprazer , Prazer/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Vias Aferentes/fisiologia , Idoso , Cordotomia , Emoções/fisiologia , Feminino , Humanos , Masculino , Mecanorreceptores/metabolismo , Mecanorreceptores/fisiologia , Pessoa de Meia-Idade , Fibras Nervosas Amielínicas/metabolismo , Fibras Nervosas Amielínicas/fisiologia , Estimulação Física , Prurido/fisiopatologia , Pele/fisiopatologia , Tratos Espinotalâmicos/metabolismo , Tratos Espinotalâmicos/fisiologia
12.
Curr Biol ; 29(24): R1301-R1303, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31846674

RESUMO

Humans localize touch on hand-held tools by interpreting the unique vibratory patterns elicited by impact to different parts of the tool. This perceptual strategy differs markedly from localizing touch on the skin. A new study shows that, nonetheless, touch location is probably processed similarly for skin and tool already early in somatosensory cortex.


Assuntos
Percepção do Tato , Tato , Humanos , Pele , Córtex Somatossensorial
13.
PLoS One ; 14(12): e0224174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31841510

RESUMO

Body ownership relies on spatiotemporal correlations between multisensory signals and visual cues specifying oneself such as body form and orientation. The mechanism for the integration of bodily signals remains unclear. One approach to model multisensory integration that has been influential in the multisensory literature is Bayesian causal inference. This specifies that the brain integrates spatial and temporal signals coming from different modalities when it infers a common cause for inputs. As an example, the rubber hand illusion shows that visual form and orientation cues can promote the inference of a common cause (one's body) leading to spatial integration shown by a proprioceptive drift of the perceived location of the real hand towards the rubber hand. Recent studies investigating the effect of visual cues on temporal integration, however, have led to conflicting findings. These could be due to task differences, variation in ecological validity of stimuli and/or small samples. In this pre-registered study, we investigated the influence of visual information on temporal integration using a visuo-tactile temporal order judgement task with realistic stimuli and a sufficiently large sample determined by Bayesian analysis. Participants viewed videos of a touch being applied to plausible or implausible visual stimuli for one's hand (hand oriented plausibly, hand rotated 180 degrees, or a sponge) while also being touched at varying stimulus onset asynchronies. Participants judged which stimulus came first: viewed or felt touch. Results show that visual cues do not modulate visuo-tactile temporal order judgements. This is not in line with the idea that bodily signals indicating oneself influence the integration of multisensory signals in the temporal domain. The current study emphasises the importance of rigour in our methodologies and analyses to advance the understanding of how properties of multisensory events affect the encoding of temporal information in the brain.


Assuntos
Orientação Espacial/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Teorema de Bayes , Imagem Corporal , Sinais (Psicologia) , Feminino , Mãos , Humanos , Masculino , Pessoa de Meia-Idade , Orientação , Propriocepção/fisiologia , Tato/fisiologia
14.
Anesth Analg ; 129(6): 1557-1560, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31743175

RESUMO

BACKGROUND: Anesthesia providers' hand hygiene practices in the operating room may contribute to the transmission of bacteria. There is a debate, however, over the best approaches for pathogen containment during task dense periods (induction and extubation) of anesthesia care. A novel approach to reducing pathogen spread during these task dense periods is the use of alcohol-based hand rub on gloves when it may be difficult to either change gloves or clean hands. METHODS: To evaluate the impact of alcohol-based hand rub on gloves, we estimated perforation rates of 50 gloves that were worn as pairs by volunteers for 2 hours at a time applying alcohol-based hand rub every 15 minutes (total of 8 alcohol-based hand rub applications per pair of gloves). We also identified perforation rates of 50 new, unused gloves. To evaluate the ability to perform routine anesthesia functions, volunteers were asked to pick up a coin from a table top and document whether the gloves felt normal or sticky at each 15-minute period. RESULTS: Fifty new gloves (not exposed to alcohol-based hand rub) were tested for integrity using the Food and Drug Administration-approved process, and one was found to have a microperforation. Of the 50 gloves that had been applied with alcohol-based hand rub 8 times, no microperforations were identified. All volunteers demonstrated tactile competence by picking up a coin from a table top after 8 alcohol-based hand rub applications; in addition, as the number of alcohol-based hand rub applications progressed, the volunteers reported increased stickiness. CONCLUSIONS: This study suggests that the use of alcohol-based hand rub on commonly used nitrile examination gloves does not compromise glove integrity or hamper the ability to safely perform routine anesthesia functions.


Assuntos
Anestesiologistas , Contaminação de Equipamentos/prevenção & controle , Etanol , Luvas Cirúrgicas , Desinfecção das Mãos/métodos , Higienizadores de Mão , Controle de Infecções/métodos , Salas Cirúrgicas , Atitude do Pessoal de Saúde , Falha de Equipamento , Etanol/efeitos adversos , Luvas Cirúrgicas/efeitos adversos , Higienizadores de Mão/efeitos adversos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Teste de Materiais , Padrões de Prática Médica , Percepção do Tato
15.
Nature ; 575(7783): 453-454, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31748719
16.
Proc Natl Acad Sci U S A ; 116(49): 24861-24871, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31732670

RESUMO

Topographic sensory maps are a prominent feature of the adult primate brain. Here, we asked whether topographic representations of the body are present at birth. Using functional MRI (fMRI), we find that the newborn somatomotor system, spanning frontoparietal cortex and subcortex, comprises multiple topographic representations of the body. The organization of these large-scale body maps was indistinguishable from those in older monkeys. Finer-scale differentiation of individual fingers increased over the first 2 y, suggesting that topographic representations are refined during early development. Last, we found that somatomotor representations were unchanged in 2 visually impaired monkeys who relied on touch for interacting with their environment, demonstrating that massive shifts in early sensory experience in an otherwise anatomically intact brain are insufficient for driving cross-modal plasticity. We propose that a topographic scaffolding is present at birth that both directs and constrains experience-driven modifications throughout somatosensory and motor systems.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Macaca mulatta/anatomia & histologia , Córtex Somatossensorial/anatomia & histologia , Animais , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/fisiologia , Feminino , Dedos/fisiologia , Macaca mulatta/crescimento & desenvolvimento , Macaca mulatta/fisiologia , Imagem por Ressonância Magnética , Masculino , Neurônios Motores , Vias Neurais/fisiologia , Plasticidade Neuronal , Células Receptoras Sensoriais , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/crescimento & desenvolvimento , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Percepção do Tato/fisiologia
17.
Acta Psychol (Amst) ; 201: 102950, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31698171

RESUMO

Considering object identification and recognition as well as human interaction with objects, texture as a surface property plays a crucial role. A deeper understanding of tactile aesthetics can be useful in the applied field such as in product designs that appeal more to our senses and that are more effective in eliciting certain emotional responses from a potential consumer. In the present study, behavioral experiments were performed using unfamiliar custom-made dot pattern stimuli under two complementary questionings. The first question focused on the tactile perceptive attributes related to topographical characteristics of the textures exhibited by the material surfaces. The second question focused on the texture pleasantness related both to the perceptive attributes and to the topographical characteristics of the textures. The perspective of this work opens on complementary fields of research such as neurosciences to determine the brain mechanisms in the processing of the pleasantness of tactile stimuli.


Assuntos
Estética/psicologia , Ódio , Percepção do Tato/fisiologia , Tato/fisiologia , Vibração , Adulto , Emoções/fisiologia , Feminino , Humanos , Masculino , Reconhecimento Psicológico/fisiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-31757089

RESUMO

No effective and easily implemented intervention strategies for reducing sedentary behavior have been established. This pilot trial (UMIN000024372) investigated whether vibrotactile feedback reduces sedentary behavior. Twenty-six adults aged 30-69 years who were sedentary ≥8 h/day were randomly assigned to control (n = 13) or vibration (n = 13) groups. Participants wore a monitor 9 h daily for seven-day periods at baseline (week zero), during the intervention (weeks one, three, five, and seven), and after the intervention (week eight). During the eight-week intervention, vibration-group participants were notified by a vibration through the monitor whenever continuous sedentary time reached ≥30 min; they also received weekly reports of their sedentary patterns. Control-group participants did not receive feedback. The primary outcome was change in total sedentary time. Changes in longer bouts of sedentary time (≥35 min) were also assessed. No significant difference was found in the change in total sedentary time (control: -17.5 min/9 h, vibration: -9.1 min/9 h; p = 0.42). Although no significant differences were observed in sedentary time in longer bouts, vibration-group participants exhibited significantly lower sedentary time (-21.6 min/9 h, p = 0.045). Thus, vibration feedback does not appear to offer any advantages in reducing total sedentary time.


Assuntos
Exercício Físico/psicologia , Retroalimentação Sensorial , Promoção da Saúde/métodos , Comportamento Sedentário , Vibração , Actigrafia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Fatores de Tempo , Percepção do Tato
19.
Neuron ; 104(4): 749-764.e6, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31586516

RESUMO

Tactile stimuli are integrated and processed by neuronal circuits in the deep dorsal horn of the spinal cord. Several spinal interneuron populations have been implicated in tactile information processing. However, dorsal horn projection neurons that contribute to the postsynaptic dorsal column (PSDC) pathway transmitting tactile information to the brain are poorly characterized. Here, we show that spinal neurons marked by the expression of Zic2creER mediate light touch sensitivity and textural discrimination. A subset of Zic2creER neurons are PSDC neurons that project to brainstem dorsal column nuclei, and chemogenetic activation of Zic2 PSDC neurons increases sensitivity to light touch stimuli. Zic2 neurons receive direct input from the cortex and brainstem motor nuclei and are required for corrective motor movements. These results suggest that Zic2 neurons integrate sensory input from cutaneous afferents with descending signals from the brain to promote corrective movements and transmit processed touch information back to the brain. VIDEO ABSTRACT.


Assuntos
Movimento/fisiologia , Células do Corno Posterior/fisiologia , Percepção do Tato/fisiologia , Animais , Camundongos , Camundongos Transgênicos , Células do Corno Posterior/citologia
20.
Elife ; 82019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31663507

RESUMO

The active properties of dendrites can support local nonlinear operations, but previous imaging and electrophysiological measurements have produced conflicting views regarding the prevalence and selectivity of local nonlinearities in vivo. We imaged calcium signals in pyramidal cell dendrites in the motor cortex of mice performing a tactile decision task. A custom microscope allowed us to image the soma and up to 300 µm of contiguous dendrite at 15 Hz, while resolving individual spines. New analysis methods were used to estimate the frequency and spatial scales of activity in dendritic branches and spines. The majority of dendritic calcium transients were coincident with global events. However, task-associated calcium signals in dendrites and spines were compartmentalized by dendritic branching and clustered within branches over approximately 10 µm. Diverse behavior-related signals were intermingled and distributed throughout the dendritic arbor, potentially supporting a large learning capacity in individual neurons.


Assuntos
Tomada de Decisões , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Células Piramidais/fisiologia , Animais , Sinalização do Cálcio , Camundongos , Microscopia , Percepção do Tato , Vibrissas/fisiologia
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