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1.
Neuroscience ; 464: 1-2, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34016292
2.
Science ; 372(6544): 791-792, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34016768
3.
Nat Commun ; 12(1): 2000, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33790301

RESUMO

A crucial role of cortical networks is the conversion of sensory inputs into perception. In the cortical somatosensory network, neurons of the primary somatosensory cortex (S1) show invariant sensory responses, while frontal lobe neuronal activity correlates with the animal's perceptual behavior. Here, we report that in the secondary somatosensory cortex (S2), neurons with invariant sensory responses coexist with neurons whose responses correlate with perceptual behavior. Importantly, the vast majority of the neurons fall along a continuum of combined sensory and categorical dynamics. Furthermore, during a non-demanding control task, the sensory responses remain unaltered while the sensory information exhibits an increase. However, perceptual responses and the associated categorical information decrease, implicating a task context-dependent processing mechanism. Conclusively, S2 neurons exhibit intriguing dynamics that are intermediate between those of S1 and frontal lobe. Our results contribute relevant evidence about the role that S2 plays in the conversion of touch into perception.


Assuntos
Macaca mulatta/fisiologia , Neurônios/fisiologia , Células Receptoras Sensoriais/fisiologia , Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Algoritmos , Animais , Lobo Frontal/citologia , Lobo Frontal/fisiologia , Modelos Neurológicos , Estimulação Física/métodos , Córtex Somatossensorial/citologia
4.
Atten Percept Psychophys ; 83(4): 1766-1776, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33709326

RESUMO

Haptic texture perception is based on sensory information sequentially gathered during several lateral movements ("strokes"). In this process, sensory information of earlier strokes must be preserved in a memory system. We investigated whether this system may be a haptic sensory memory. In the first experiment, participants performed three strokes across each of two textures in a frequency discrimination task. Between the strokes over the first texture, participants explored an intermediate area, which presented either a mask (high-energy tactile pattern) or minimal stimulation (low-energy smooth surface). Perceptual precision was significantly lower with the mask compared with a three-strokes control condition without an intermediate area, approaching performance in a one-stroke-control condition. In contrast, precision in the minimal stimulation condition was significantly better than in the one-stroke control condition and similar to the three-strokes control condition. In a second experiment, we varied the number of strokes across the first stimulus (one, three, five, or seven strokes) and either presented no masking or repeated masking after each stroke. Again, masking between the strokes decreased perceptual precision relative to the control conditions without masking. Precision effects of masking over different numbers of strokes were fit by a proven model on haptic serial integration (Lezkan & Drewing, Attention, Perception, & Psychophysics 80(1): 177-192, 2018b) that modeled masking by repeated disturbances in the ongoing integration. Taken together, results suggest that masking impedes the processes of haptic information preservation and integration. We conclude that a haptic sensory memory, which is comparable to iconic memory in vision, is used for integrating sequentially gathered sensory information.


Assuntos
Percepção do Tato , Humanos , Movimento , Mascaramento Perceptivo , Psicofísica , Tato , Percepção Visual
5.
Neurosci Lett ; 750: 135805, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33705926

RESUMO

Research has confirmed that the visual working memory representation of objects' roughness is robust against illumination changes in the human ventral visual cortex and intraparietal sulcus, but not yet against visual distractors during memory maintenance. Thus, this study investigated the effects of visual distractors on roughness-related brain regions during the maintenance phase using multi-voxel pattern analysis (MVPA). We conducted an fMRI experiment in which participants were asked to memorize a sphere's roughness against visual distractors, presented during the delay period in random trials. Region of interest-based MVPA showed no contribution of the ventral visual cortex and intraparietal sulcus to the roughness memory, regardless of behavioral performance. Post hoc searchlight MVPA revealed an above-chance decoding performance level in the brain regions presumably related to haptic processing when no visual distractors were shown. In contrast, when visual distractors appeared in the delay period, decoding performance exceeded the chance level in the ventral visual cortex. These results suggest that when visual distractors are presented during the memory phase, both visual and haptic processing are related to visual working memory for roughness, and the weighting of modality changes depending on the presence of visual distractors.


Assuntos
Memória de Curto Prazo , Percepção do Tato , Córtex Visual/fisiologia , Percepção Visual , Atenção , Conectoma , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Parietal/fisiologia , Adulto Jovem
6.
Sensors (Basel) ; 21(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668561

RESUMO

Tactile sensation is a promising information display channel for human beings that involves supplementing or replacing degraded visual or auditory channels. In this paper, a wrist-wearable tactile rendering system based on electro-tactile stimulation is designed for information expression, where a square array with 8 × 8 spherical electrodes is used as the touch panel. To verify and improve this touch-based information display method, the optimal mode for stimulus signals was firstly investigated through comparison experiments, which show that sequential stimuli with consecutive-electrode-in-active mode have a better performance than those with single-electrode-in-active mode. Then, simple Chinese and English characters and 26 English characters' recognition experiments were carried out and the proposed method was verified with an average recognition rate of 95% and 82%, respectively. This wrist-wearable tactile display system would be a new and promising medium for communication and could be of great value for visually impaired people.


Assuntos
Percepção do Tato , Pessoas com Deficiência Visual , Dispositivos Eletrônicos Vestíveis , Humanos , Punho , Articulação do Punho
7.
Artigo em Inglês | MEDLINE | ID: mdl-33668108

RESUMO

The sense of touch is the first manner of contact with the external world, providing a foundation for the development of sensorimotor skills and socio-affective behaviors. In particular, affective touch is at the core of early interpersonal interactions and the developing bodily self, promoting the balance between internal physiological state and responsiveness to external environment. The aim of the present study is to investigate whether newborns are able to discriminate between affective touch and non-affective somatosensory stimulations and whether affective touch promotes a positive physiological state. We recorded full-term newborns' (N = 30) heart rate variability (HRV)-which reflects oscillations of heart rate associated with autonomic cardio-respiratory regulation-while newborns were presented with two minutes of affective (stroking) and non-affective (tapping) touch alternated with two minutes of resting in a within-subject design. The results revealed that non-affective touch elicits a decrease in HRV, whereas affective touch does not result in a change of HRV possibly indicating maintenance of calm physiological state. Thus, newborns showed cardiac sensitivity to different types of touch, suggesting that early somatosensory stimulation represents scaffolding for development of autonomic self-regulation with important implications on infant's ability to adaptively respond to the surrounding social and physical environment.


Assuntos
Toque Terapêutico , Percepção do Tato , Emoções , Frequência Cardíaca , Humanos , Lactente , Recém-Nascido , Tato
8.
J R Soc Interface ; 18(176): 20200783, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33784888

RESUMO

Electrovibration holds great potential for creating vivid and realistic haptic sensations on touchscreens. Ideally, a designer should be able to control what users feel independent of the number of fingers they use, the movements they make, and how hard they press. We sought to understand the perception and physics of such interactions by determining the smallest 125 Hz electrovibration voltage that 15 participants could reliably feel when performing four different touch interactions at two normal forces. The results proved for the first time that both finger motion and contact by a second finger significantly affect what the user feels. At a given voltage, a single moving finger experiences much larger fluctuating electrovibration forces than a single stationary finger, making electrovibration much easier to feel during interactions involving finger movement. Indeed, only about 30% of participants could detect the stimulus without motion. Part of this difference comes from the fact that relative motion greatly increases the electrical impedance between a finger and the screen, as shown via detailed measurements from one individual. By contrast, threshold-level electrovibration did not significantly affect the coefficient of kinetic friction in any conditions. These findings help lay the groundwork for delivering consistent haptic feedback via electrovibration.


Assuntos
Percepção do Tato , Vibração , Adulto , Feminino , Dedos , Fricção , Humanos , Masculino , Movimento (Física)
9.
J Neuroeng Rehabil ; 18(1): 34, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588877

RESUMO

BACKGROUND: Fine tactile sensation plays an important role in motor relearning after stroke. However, little is known about its dynamics in post-stroke recovery, principally due to a lack of effective evaluation on neural responses to fine tactile stimulation. This study investigated the post-stroke alteration of cortical connectivity and its functional structure in response to fine tactile stimulation via textile fabrics by electroencephalogram (EEG)-derived functional connectivity and graph theory analyses. METHOD: Whole brain EEG was recorded from 64 scalp channels in 8 participants with chronic stroke and 8 unimpaired controls before and during the skin of the unilateral forearm contacted with a piece of cotton fabric. Functional connectivity (FC) was then estimated using EEG coherence. The fabric stimulation induced FC (SFC) was analyzed by a cluster-based permutation test for the FC in baseline and fabric stimulation. The functional structure of connectivity alteration in the brain was also investigated by assessing the multiscale topological properties of functional brain networks according to the graph theory. RESULTS: In the SFC distribution, an altered hemispheric lateralization (HL) (HL degree, 14%) was observed when stimulating the affected forearm in the stroke group, compared to stimulation of the unaffected forearm of the stroke group (HL degree, 53%) and those of the control group (HL degrees, 92% for the left and 69% for the dominant right limb). The involvement of additional brain regions, i.e., the distributed attention networks, was also observed when stimulating either limb of the stroke group compared with those of the control. Significantly increased (P < 0.05) global and local efficiencies were found when stimulating the affected forearm compared to the unaffected forearm. A significantly increased (P < 0.05) degree of inter-hemisphere FC (interdegree) mainly within ipsilesional somatosensory region and a significantly diminished degree of intra-hemisphere FC (intradegree) (P < 0.05) in ipsilesional primary somatosensory region were observed when stimulating the affected forearm, compared with the unaffected forearm. CONCLUSIONS: The alteration of cortical connectivity in fine tactile sensation post-stroke was characterized by the compensation from the contralesional hemisphere and distributed attention networks related to involuntary attention. The interhemispheric connectivity could implement the compensation from the contralateral hemisphere to the ipsilesional somatosensory region. Stroke participants also exerted increased cortical activities in fine tactile sensation.


Assuntos
Vias Neurais/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Percepção do Tato/fisiologia , Tato/fisiologia , Adulto , Idoso , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Neuroscience ; 464: 53-58, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33607227

RESUMO

Ageing is accompanied by a steady decline in touch sensitivity and acuity. Conversely, pleasant touch, such as experienced during a caress, is even more pleasant in old age. There are many physiological changes that might explain these perceptual changes, but researchers have not yet identified any specific mechanisms. Here, we review both the perceptual and structural changes to the touch system that are associated with ageing. The structural changes include reduced elasticity of the skin in older people, as well as reduced numbers and altered morphology of skin tactile receptors. Effects of ageing on the peripheral and central nervous systems include demyelination, which affects the timing of neural signals, as well as reduced numbers of peripheral nerve fibres. The ageing brain also undergoes complex changes in blood flow, metabolism, plasticity, neurotransmitter function, and, for touch, the body map in primary somatosensory cortex. Although several studies have attempted to find a direct link between perceptual and structural changes, this has proved surprisingly elusive. We also highlight the need for more evidence regarding age-related changes in peripheral nerve function in the hairy skin, as well as the social and emotional aspects of touch.


Assuntos
Percepção do Tato , Idoso , Envelhecimento , Humanos , Estimulação Física , Pele , Córtex Somatossensorial
11.
Sensors (Basel) ; 21(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525367

RESUMO

HumTouch is a touch sensing technology utilizing the environmental electromagnetic wave. The method can be realized using conductive and semi-conductive materials by simply attaching electrodes to the object's surface. In this study, we compared three methods for localizing a touch on 20×16cm2 and 40×36cm2 papers, on which four or eight electrodes were attached to record the voltages leaked from the human fingertip. The number and positions of the electrodes and the data processing of the voltages differed according to the localization methods. By constructing a kernel regression analysis model between the electrode outputs and the actual physical locations, the touched locations were estimated. Each of the three methods was tested via leave-one-out cross validation. Out of the three methods discussed, two exhibited superior performances in terms of the estimation errors. Of these two methods, one simply uses the voltages recorded by the four electrodes attached on the middle of paper edges as inputs to the regression system. The other uses differential outputs of electrode pairs as the inputs. The smallest mean location errors were 0.31 cm on 20×16cm2 paper and 0.27 cm on 40×36cm2 paper, which are smaller than the size of a fingertip.


Assuntos
Percepção do Tato , Tato , Condutividade Elétrica , Eletrodos , Dedos , Corpo Humano , Humanos
12.
eNeuro ; 8(2)2021.
Artigo em Inglês | MEDLINE | ID: mdl-33593733

RESUMO

Tactile sensation is one of our primary means to collect information about the nearby environment and thus crucial for daily activities and survival. Therefore, it is of high importance to restore sensory feedback after sensory loss. Optogenetic manipulation allows local or pathway-specific write-in of information. However, it remains elusive whether optogenetic stimulation can be interpreted as tactile sensation to guide operant behavior and how it is integrated with tactile stimuli. To address these questions, we employed a vibrotactile detection task combined with optogenetic neuromodulation in freely moving rats. By bidirectionally manipulating the activity of neurons in primary somatosensory cortex (S1), we demonstrated that optical activation as well as inhibition of S1 reduced the detection rate for vibrotactile stimuli. Interestingly, activation of corticostriatal terminals improved the detection of tactile stimuli, while inhibition of corticostriatal terminals did not affect the performance. To manipulate the corticostriatal pathway more specifically, we employed a dual viral system. Activation of corticostriatal cell bodies disturbed the tactile perception while activation of corticostriatal terminals slightly facilitated the detection of vibrotactile stimuli. In the absence of tactile stimuli, both corticostriatal cell bodies as well as terminals caused a reaction. Taken together, our data confirmed the possibility to restore sensation using optogenetics and demonstrated that S1 and its descending projections to striatum play differential roles in the neural processing underlying vibrotactile detection.


Assuntos
Córtex Somatossensorial , Percepção do Tato , Animais , Corpo Estriado , Optogenética , Ratos , Tato
13.
J Psychiatr Res ; 134: 208-214, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33418447

RESUMO

According to the dimensional approach to psychosis, there is a continuum from low schizotypy to schizophrenia patients. The temporal aspect of sensory processing seems to be compromised across such continuum, as suggested by different studies separately investigating unisensory or multisensory domains. Most of these studies have so far focused primarily on the temporal processing of visual and auditory stimuli, either in schizotypy or schizophrenia, while leaving the tactile domain and the integration of touch with other senses mostly unexplored. Given the relevance of body-related perceptual abnormalities for psychosis proneness, we aimed at filling this gap in the literature across two studies. We asked participants with increasing levels of schizotypy (study 1) and schizophrenia patients (study 2) to perform three simultaneity judgement tasks: a unimodal tactile task, a unimodal auditory task and a bimodal audio-tactile task. Each task allowed estimating a simultaneity range (SR), as a proxy of the individual tolerance to asynchronies in the tactile, auditory and audio-tactile domains, respectively. Results showed larger SRs as the level of schizotypy increases. Specifically, the linear effect of schizotypy levels on the audio-tactile task was stronger than on the auditory task, which in turn was greater than the effect on the tactile task (study 1). Differently, schizophrenia patients showed larger SRs than controls in all the three tasks (study 2). The current study is the first empirical investigation across the continuum from low schizotypy to schizophrenia of the tolerance to asynchronies in the processing of external (auditory) and body-related (tactile) inputs.


Assuntos
Esquizofrenia , Percepção do Tempo , Percepção do Tato , Estimulação Acústica , Percepção Auditiva , Humanos , Tato , Percepção Visual
14.
Dev Neurorehabil ; 24(4): 276-286, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33393402

RESUMO

Motor disorders in cerebral palsy (CP) are often accompanied by disturbances of sensation and impaired somatosensory functions have been reported in individuals with CP. To test the feasibility of a sensorimotor training protocol for lower limbs in children and adolescents with unilateral and bilateral CP, and to analyze the preliminary effects of this training on sensory and motor variables. This is a single-blind, prospective phase I feasibility randomized protocol. A total of twenty participants with uni or bilateral cerebral palsy, GMFCS level I-III, ages 5 to 20 years will be recruited. The LoSenseT protocol is composed of tactile and proprioceptive activities in a child-friendly format. An original qualitative feedback questionnaire was developed to assess the protocol feasibility. Additionally, proprioception, tactile discrimination, postural stability, and gait parameters will be assessed. The LoSenseT protocol can support the implementation of interventions targeting lower limbs somatosensory impairments in individuals with CP.


Assuntos
Paralisia Cerebral/reabilitação , Terapia por Exercício/métodos , Reabilitação Neurológica/métodos , Propriocepção , Adolescente , Paralisia Cerebral/fisiopatologia , Criança , Pré-Escolar , Feminino , Marcha , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Equilíbrio Postural , Percepção do Tato , Adulto Jovem
15.
J Neuroeng Rehabil ; 18(1): 12, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478534

RESUMO

BACKGROUND: Electrical stimulation of residual afferent nerve fibers can evoke sensations from a missing limb after amputation, and bionic arms endowed with artificial sensory feedback have been shown to confer functional and psychological benefits. Here we explore the extent to which artificial sensations can be discriminated based on location, quality, and intensity. METHODS: We implanted Utah Slanted Electrode Arrays (USEAs) in the arm nerves of three transradial amputees and delivered electrical stimulation via different electrodes and frequencies to produce sensations on the missing hand with various locations, qualities, and intensities. Participants performed blind discrimination trials to discriminate among these artificial sensations. RESULTS: Participants successfully discriminated cutaneous and proprioceptive sensations ranging in location, quality and intensity. Performance was significantly greater than chance for all discrimination tasks, including discrimination among up to ten different cutaneous location-intensity combinations (15/30 successes, p < 0.0001) and seven different proprioceptive location-intensity combinations (21/40 successes, p < 0.0001). Variations in the site of stimulation within the nerve, via electrode selection, enabled discrimination among up to five locations and qualities (35/35 successes, p < 0.0001). Variations in the stimulation frequency enabled discrimination among four different intensities at the same location (13/20 successes, p < 0.0005). One participant also discriminated among individual stimulation of two different USEA electrodes, simultaneous stimulation on both electrodes, and interleaved stimulation on both electrodes (20/24 successes, p < 0.0001). CONCLUSION: Electrode location, stimulation frequency, and stimulation pattern can be modulated to evoke functionally discriminable sensations with a range of locations, qualities, and intensities. This rich source of artificial sensory feedback may enhance functional performance and embodiment of bionic arms endowed with a sense of touch.


Assuntos
Membros Artificiais , Estimulação Elétrica/instrumentação , Propriocepção/fisiologia , Percepção do Tato/fisiologia , Adulto , Amputados , Braço , Eletrodos , Retroalimentação Sensorial/fisiologia , Mãos , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Neuroeng Rehabil ; 18(1): 14, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485371

RESUMO

OBJECTIVE: Evaluate the feasibility and potential impacts on hand function using a wearable stimulation device (the VTS Glove) which provides mechanical, vibratory input to the affected limb of chronic stroke survivors. METHODS: A double-blind, randomized, controlled feasibility study including sixteen chronic stroke survivors (mean age: 54; 1-13 years post-stroke) with diminished movement and tactile perception in their affected hand. Participants were given a wearable device to take home and asked to wear it for three hours daily over eight weeks. The device intervention was either (1) the VTS Glove, which provided vibrotactile stimulation to the hand, or (2) an identical glove with vibration disabled. Participants were randomly assigned to each condition. Hand and arm function were measured weekly at home and in local physical therapy clinics. RESULTS: Participants using the VTS Glove showed significantly improved Semmes-Weinstein monofilament exam results, reduction in Modified Ashworth measures in the fingers, and some increased voluntary finger flexion, elbow and shoulder range of motion. CONCLUSIONS: Vibrotactile stimulation applied to the disabled limb may impact tactile perception, tone and spasticity, and voluntary range of motion. Wearable devices allow extended application and study of stimulation methods outside of a clinical setting.


Assuntos
Modalidades de Fisioterapia/instrumentação , Reabilitação do Acidente Vascular Cerebral/instrumentação , Percepção do Tato/fisiologia , Vibração/uso terapêutico , Dispositivos Eletrônicos Vestíveis , Idoso , Método Duplo-Cego , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tono Muscular , Amplitude de Movimento Articular , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiopatologia
17.
Neuroscience ; 464: 44-52, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33385487

RESUMO

Slow stroking touch activates C-tactile (CT) fibres in the human skin and is typically described as pleasant. Over a longer duration of stroking, affective habituation sets in, indicated by a reduction in rated pleasantness. However, it is not clear whether the group level effect is represented on an individual level. We analyse the stability of individual ratings of slow stroking touch and their relationship to behavioural and physiological measures. Forty-eight participants (23 women) were repeatedly stroked with a velocity maximally activating CT fibres. The perceived pleasantness was rated on a visual analogue scale. In order to examine the stability of pleasantness ratings, the experiment was repeated after a couple of days. During the experiment, electrocardiogram (ECG) and facial-electromyography (EMG) data were recorded. On the group-level, previous results of affective habituation to touch were replicated and stable across sessions. On the individual level, however, less than half of the participants showed a significant reduction of pleasantness in the course of the experiment. Moreover, the remaining participants showed either no change, random rating behaviour or even an increase in pleasantness ratings during the course of the experiment. The individual response patterns were variable across sessions but stable above the chance level. Furthermore, the response patterns could not be explicitly associated with any of the behavioural or physiological measures. Our findings indicate a lack of group-to-individual generalizability for affective habituation to touch. The variability of rating patterns over time indicates that they are not conclusively determined by stable individual characteristics. Future research investigating touch should favour a more individual approach to the more commonly applied group analysis.


Assuntos
Percepção do Tato , Tato , Feminino , Habituação Psicofisiológica , Humanos , Estimulação Física , Pele
18.
Neuroscience ; 464: 26-32, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33385489

RESUMO

Gentle stroking, a type of affective touch that holds hedonic and rewarding value, is critical to our daily inter-individual communication. This positive socio-emotional aspect of touch is conveyed through a subclass of C afferents known as C-Tactile fibers in humans with an analogous system in rodents proposed. Here, we describe a novel tactile conditioned place preference paradigm using mice and demonstrate that gentle stroking by an experimenter is rewarding. In order to investigate the relationship between tactile preference and innate sociability, mice were subjected to the classic three-chambered test of social approach, where mice displayed significant preference towards the experimenter's hand. These findings suggest that gentle stroking evoked by an experimenter can play an important role in reward and preference and establish an affiliative relationship between mice and humans. Future research can potentially use this model to examine fiber type involvement and elucidate the significance of these findings for activation of the reward system.


Assuntos
Percepção do Tato , Animais , Emoções , Masculino , Camundongos , Fibras Nervosas Amielínicas , Estimulação Física , Tato
19.
Neuron ; 109(5): 778-787.e3, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33472037

RESUMO

Fast synaptic transmission relies upon the activation of ionotropic receptors by neurotransmitter release to evoke postsynaptic potentials. Glutamate and GABA play dominant roles in driving highly dynamic activity in synaptically connected neuronal circuits, but ionotropic receptors for other neurotransmitters are also expressed in the neocortex, including nicotinic receptors, which are non-selective cation channels gated by acetylcholine. To study the function of non-glutamatergic excitation in neocortex, we used two-photon microscopy to target whole-cell membrane potential recordings to different types of genetically defined neurons in layer 2/3 of primary somatosensory barrel cortex in awake head-restrained mice combined with pharmacological and optogenetic manipulations. Here, we report a prominent nicotinic input, which selectively depolarizes a subtype of GABAergic neuron expressing vasoactive intestinal peptide leading to disinhibition during active sensorimotor processing. Nicotinic disinhibition of somatosensory cortex during active sensing might contribute importantly to integration of top-down and motor-related signals necessary for tactile perception and learning.


Assuntos
Neurônios GABAérgicos/fisiologia , Receptores Nicotínicos/fisiologia , Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Animais , Comportamento Animal , Feminino , Masculino , Potenciais da Membrana , Neurônios/fisiologia , Optogenética , Tato/fisiologia , Peptídeo Intestinal Vasoativo/análise , Vibrissas/fisiologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-33445696

RESUMO

Stress is a physiological response to internal and external events we call "stressors". Response to the same daily stressors varies across individuals and seems to be higher for women. A possible explanation for this phenomenon is that women perceive sociality, relationships, and intimacy-important sources of both stress and wellbeing-differently from how men experience them. In this study, we investigate how gender, attachment, and touch avoidance predict stress responses on a sample of 335 Italians (216 females; age = 35.82 ± 14.32). Moreover, we analyze the network of relationships between these variables through multiple linear regression and exploratory network analysis techniques. The results recontextualize the role of gender in determining stress responses in terms of (lack of) confidence and touch avoidance toward family members; attitudes toward relationships seem to be the main determinants of stress responses. These results have implications for reducing stress in both clinical settings and at a social level.


Assuntos
Percepção do Tato , Tato , Adulto , Feminino , Identidade de Gênero , Humanos , Relações Interpessoais , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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