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1.
PLoS One ; 18(11): e0286512, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37992062

RESUMO

Face perception in humans and nonhuman primates is accomplished by a patchwork of specialized cortical regions. How these regions develop has remained controversial. In sighted individuals, facial information is primarily conveyed via the visual modality. Early blind individuals, on the other hand, can recognize shapes using auditory and tactile cues. Here we demonstrate that such individuals can learn to distinguish faces from houses and other shapes by using a sensory substitution device (SSD) presenting schematic faces as sound-encoded stimuli in the auditory modality. Using functional MRI, we then asked whether a face-selective brain region like the fusiform face area (FFA) shows selectivity for faces in the same subjects, and indeed, we found evidence for preferential activation of the left FFA by sound-encoded faces. These results imply that FFA development does not depend on experience with visual faces per se but may instead depend on exposure to the geometry of facial configurations.


Assuntos
Reconhecimento Facial , Reconhecimento Visual de Modelos , Animais , Humanos , Reconhecimento Visual de Modelos/fisiologia , Mapeamento Encefálico/métodos , Face/fisiologia , Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Estimulação Luminosa/métodos
2.
Front Psychiatry ; 13: 904283, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35800026

RESUMO

Objective: We aimed to evaluate the feasibility of an online High-Intensity Interval Training (HIIT) program on clinical psychological symptoms in higher education students in the context of the COVID-19 pandemic lockdown. Materials and Methods: During the lockdown, 30 students aged 18-25 years, who had been screened previously with a cut-off score ≥5 in the Generalized Anxiety Disorder-7 (GAD-7) questionnaire, were randomly assigned to either the 4-week HIIT program with three sessions per week conducted through online videos, or a no-intervention control group. The primary outcome was the feasibility assessment. The secondary outcome was a psychological self-report with the 21-items Depression, Anxiety, and Stress Scale (DASS-21). Assessment and intervention were performed in compliance with social distancing rules. Results: Two participants in the HIIT were lost to follow-up, leaving 13 participants vs. 15 in the control group. We observed high adherence (87%) and complete safety for mental and physical status with the HIIT intervention delivered by online videos. The Mann-Whitney test demonstrated a significant (group × time, P-Value = 0.046) reduction of clinical stress symptoms and a trend (group × time, P-Value = 0.08) toward reduction of clinical depression symptoms, both favoring the HIIT group. No significant (group × time, P-Value = 0.118) interaction was found for anxiety symptoms. Conclusion: The online HIIT program was found to be feasible and safe in a clinical sample of young adults, who were experiencing social and physical restrictions due to COVID-19. HIIT reduced stress and depressive symptoms and thus these preliminary results show promise for broader application among higher education students during the present lockdown necessitated by the global COVID-19 health crisis.

3.
Data Brief ; 42: 108165, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35496473

RESUMO

The present data article provides a dataset of psychological scores, additional description of used measures, and descriptive data of participants related to the research article entitled "Impact of physical exercise on depression and anxiety in adolescent inpatients: a randomized controlled trial" (Philippot et al., 2022). This randomized controlled trial aimed at assessing the effect of add-on treatment with structured physical exercise compared to social relaxation activities in a clinical population of adolescents hospitalized for depression and anxiety in a psychiatric hospital. A group of 40 adolescents was randomly assigned to either a physical exercise or a control program three to four times per week over six weeks. The primary outcome was the Hospital Anxiety Depression Scale (HADS) for evaluation of depression and anxiety symptoms. Secondary outcomes were psychological self-assessments (The Zung Self-Assessment Depression Scale (SDS), Beck's abbreviated Depression Inventory (BDI-13), The Child Depression Inventory (CDI), The State-Trait Anxiety Inventory (STAI)), diagnostic interview (Hamilton Depression Rating Scale), and physical examinations (an adapted version of the Astrand-Rhyming Sub-Maximal Effort Test and BMI measures). These questionnaires and tests were filled at baseline and after intervention.

4.
J Affect Disord ; 301: 145-153, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007642

RESUMO

BACKGROUND: Physical exercise therapy is of proven efficacy in the treatment of adults with depression, but corresponding evidence is lacking in depressed adolescent inpatients. The aim of this study was to document the effect of add-on treatment with structured physical exercise in a clinical population of adolescents hospitalized for depression and anxiety in a psychiatric hospital. METHODS: A group of 52 adolescent inpatients was randomly assigned to a physical exercise or control program three to four times per week over a six-week period (20 hours in total). The primary outcome was the Hospital Anxiety Depression Scale (HADS) for evaluation of depression and anxiety symptoms. Secondary outcomes were psychological self-assessments, diagnostic interviews, and physical examinations. RESULTS: Six participants were lost in each group, leaving 20 inpatients each in the intervention and control groups. A linear mixed model with F-test revealed a significant interaction in favor of physical exercise in reducing the mean depression score (HADS-D) by 3.8 points [95% (CI), range 1.8 to 5.7], compared to a mean reduction score of 0.7 [95% (CI), range -0,7 to 2.0] in the control group. No significant interaction was found for anxiety symptoms (HADS-A). LIMITATIONS: The investigation was limited to the six-week hospital window and the small sample size prevented exploring differences in social characteristics. CONCLUSION: Structured physical exercise add-on therapy integrated into the psychiatric hospitalization of adolescents has led to a reduction in their depressive symptoms, demonstrating its effectiveness in the care of adolescent inpatients with depression.


Assuntos
Depressão , Pacientes Internados , Adolescente , Adulto , Ansiedade/psicologia , Transtornos de Ansiedade/terapia , Depressão/psicologia , Exercício Físico , Humanos
5.
Atten Percept Psychophys ; 83(7): 2995-3007, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34036536

RESUMO

Spatial locations of somatosensory stimuli are coded according to somatotopic (anatomical distribution of the sensory receptors on the skin surface) and spatiotopic (position of the body parts in external space) reference frames. This was mostly evidenced by means of temporal order judgment (TOJ) tasks in which participants discriminate the temporal order of two tactile stimuli, one applied on each hand. Because crossing the hands generates a conflict between anatomical and spatial responses, TOJ performance is decreased in such posture, except for congenitally blind people, suggesting a role of visual experience in somatosensory perception. In previous TOJ studies, stimuli were generally presented using the method of constant stimuli-that is, the repetition of a predefined sample of stimulus-onset asynchronies (SOA) separating the two stimuli. This method has the disadvantage that a large number of trials is needed to obtain reliable data when aiming at dissociating performances of groups characterized by different cognitive abilities. Indeed, each SOA among a large variety of different SOAs should be presented the same number of times irrespective of the participant's performance. This study aimed to replicate previous tactile TOJ data in sighted and blind participants with the adaptive psi method in order to validate a novel method that adapts the presented SOA according to the participant's performance. This allows to precisely estimate the temporal sensitivity of each participant while the presented stimuli are adapted to the participant's individual discrimination threshold. We successfully replicated previous findings in both sighted and blind participants, corroborating previous data using a more suitable psychophysical tool.


Assuntos
Julgamento , Tato , Cegueira , Humanos , Tempo de Reação , Percepção Espacial , Visão Ocular
6.
Life (Basel) ; 11(4)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807372

RESUMO

Using functional magnetic resonance imaging, here we monitored the brain activity in 12 early blind subjects and 12 blindfolded control subjects, matched for age, gender and musical experience, during a beat detection task. Subjects were required to discriminate regular ("beat") from irregular ("no beat") rhythmic sequences composed of sounds or vibrotactile stimulations. In both sensory modalities, the brain activity differences between the two groups involved heteromodal brain regions including parietal and frontal cortical areas and occipital brain areas, that were recruited in the early blind group only. Accordingly, early blindness induced brain plasticity changes in the cerebral pathways involved in rhythm perception, with a participation of the visually deprived occipital brain areas whatever the sensory modality for input. We conclude that the visually deprived cortex switches its input modality from vision to audition and vibrotactile sense to perform this temporal processing task, supporting the concept of a metamodal, multisensory organization of this cortex.

7.
Neurorehabil Neural Repair ; 34(6): 533-546, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32407247

RESUMO

Background. In children with unilateral cerebral palsy (UCP), the fibers of the corticospinal tract (CST) emerging from the lesioned hemisphere are damaged following the initial brain injury. The extent to which the integrity of these fibers is restorable with training is unknown. Objective. To assess changes in CST integrity in children with UCP following Hand-and-Arm-Bimanual-Intensive-Therapy-Including-Lower-Extremity (HABIT-ILE) compared to a control group. Methods. Forty-four children with UCP participated in this study. Integrity of the CSTs was measured using diffusion tensor imaging before and after 2 weeks of HABIT-ILE (treatment group, n = 23) or 2 weeks apart without intensive treatment (control group, n = 18). Fractional anisotropy (FA) and mean diffusivity (MD) were the endpoints for assessing the integrity of CST. Results. As highlighted in our whole tract analysis, the FA of the CST originating from the nonlesioned and lesioned hemispheres increased significantly after therapy in the treatment group compared to the control group (group * test session interaction: P < .001 and P = .049, respectively). A decrease in MD was also observed in the CST emerging from the nonlesioned and lesioned hemispheres (group * time interaction: both P < .001). In addition, changes in manual ability correlated with changes in FA in both CSTs (r = 0.463, P = .024; r = 0.643, P < .001) and changes in MD in CST emerging from nonlesioned hemisphere (r = -0.662, P < .001). Conclusions. HABIT-ILE improves FA/MD in the CST and hand function of children with UCP, suggesting that CST fibers retain a capacity for functional restoration. This finding supports the application of intensive motor skill training in clinical practice for the benefit of numerous patients.


Assuntos
Braço/fisiopatologia , Paralisia Cerebral/reabilitação , Destreza Motora/fisiologia , Fibras Nervosas , Reabilitação Neurológica , Prática Psicológica , Tratos Piramidais , Adolescente , Paralisia Cerebral/complicações , Paralisia Cerebral/patologia , Paralisia Cerebral/fisiopatologia , Criança , Imagem de Tensor de Difusão , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Fibras Nervosas/patologia , Fibras Nervosas/fisiologia , Reabilitação Neurológica/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde , Equilíbrio Postural/fisiologia , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/patologia , Tratos Piramidais/fisiopatologia
8.
J Vestib Res ; 30(1): 25-33, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32083606

RESUMO

BACKGROUND: The impact of vestibular loss (VL) on cognition has been previously studied in experimental animal, human and adult patient studies showing links between VL, and cognitive impairments in space orientation, working memory, mental rotation and selective attention. However, few studies have been conducted on children with VL. OBJECTIVE: We investigated for the first time, the impact of a VL on children's cognition. METHODS: 13 children with VL (10 years, 5 months) and 60 average-age matched controls performed a neuropsychological assessment consisting of visuospatial working memory, selective visual attention, mental rotation and space orientation tasks. RESULTS: Children with VL recalled smaller sequences for both forward and backward memory subtasks (mean±SD = 6.3±1.9 and 5.3±2.6) than controls (8.2±2.3 and 7.3±2.0), have less accurate mental rotation scores (25.4±6 versus 30.8±5.1) and greater additional distance travelled in the maze task (96.4±66.6 versus 60.4±66.3); all corrected p-values <0.05. Selective visual attention measures do not show significant differences. CONCLUSIONS: Children with VL show similar cognitive difficulties that adults with VL, in tasks involving dynamic cognitive processes (higher attentional load) that in tasks requiring static cognitive processes such as visual attention task.


Assuntos
Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Testes Neuropsicológicos , Doenças Vestibulares/fisiopatologia , Doenças Vestibulares/psicologia , Testes de Função Vestibular/métodos , Adolescente , Criança , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Doenças Vestibulares/diagnóstico , Vestíbulo do Labirinto/fisiopatologia
9.
Cortex ; 126: 26-38, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32062141

RESUMO

Adequately localizing pain is crucial to protect the body against physical damage and react to the stimulus in external space having caused such damage. Accordingly, it is hypothesized that nociceptive inputs are remapped from a somatotopic reference frame, representing the skin surface, towards a spatiotopic frame, representing the body parts in external space. This ability is thought to be developed and shaped by early visual experience. To test this hypothesis, normally sighted and early blind participants performed temporal order judgment tasks during which they judged which of two nociceptive stimuli applied on each hand's dorsum was perceived as first delivered. Crucially, tasks were performed with the hands either in an uncrossed posture or crossed over body midline. While early blinds were not affected by the posture, performances of the normally sighted participants decreased in the crossed condition relative to the uncrossed condition. This indicates that nociceptive stimuli were automatically remapped into a spatiotopic representation that interfered with somatotopy in normally sighted individuals, whereas early blinds seemed to mostly rely on a somatotopic representation to localize nociceptive inputs. Accordingly, the plasticity of the nociceptive system would not purely depend on bodily experiences but also on crossmodal interactions between nociception and vision during early sensory experience.


Assuntos
Nociceptividade , Percepção Espacial , Cognição , Mãos , Humanos , Julgamento
10.
Pain ; 161(2): 328-337, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31613868

RESUMO

Localizing pain is crucial because it allows for detecting which part of the body is being hurt and identifying in its surrounding which stimulus is producing the damage. Nociceptive inputs should therefore be mapped according to somatotopic ("which limb is stimulated?") and spatiotopic representations ("where is the stimulated limb?"). Because the body posture constantly changes, the brain has to realign the different spatial representations, for instance when the arms are crossed with the left hand in the right space and vice versa, to adequately guide actions towards the threatening object. Such ability is thought to be dependent on past sensory experience and contextual factors. We compared performances of early blind and normally sighted participants during temporal order judgement tasks. Two nociceptive stimuli were applied, one on each hand, with the hands either uncrossed or crossed. Participants reported which stimulus they perceived as first presented, according to either its location on the body or the position of the stimulated hand, respectively, prioritizing anatomy or external space as task-relevant reference frame. Relative to the uncrossed posture, sighted participants' performances were decreased when the hands were crossed, whatever the instruction be. Early blind participants' performances were affected by crossing the hands during spatial instruction, but not during anatomical instruction. These results indicate that nociceptive stimuli are automatically coded according to both somatotopic and spatiotopic representations, but the integration of the different spatial reference frames depends on early visual experience and ongoing cognitive goals, illustrating the plasticity and the flexibility of the nociceptive system.


Assuntos
Cegueira/fisiopatologia , Nociceptividade/fisiologia , Processamento Espacial/fisiologia , Adulto , Idade de Início , Estudos de Casos e Controles , Cognição , Feminino , Objetivos , Humanos , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal , Percepção da Dor/fisiologia , Estimulação Luminosa , Percepção Espacial/fisiologia , Percepção do Tempo , Adulto Jovem
11.
Front Psychol ; 10: 1820, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440186

RESUMO

AIM: The intensity of the most appropriate exercise to use in depressed youth is unclear due to differences in methodology and the lack of evidence documenting the effect of physical activity in children. Therefore, the authors of this study attempted to document the effectiveness of different training intensities to reduce symptoms of depression and anxiety in pre-teens. METHODS: The study included twenty-seven, randomly selected pre-adolescents (aged between 9-11 years of age) all of whom had Primary education. The participants were enrolled and, over a 5-week period, were subject to either intensive or low-to-moderate exercise programs four times a week. Psychological self-reports, as well as physical examinations, were conducted before and after such programs in blinded assessments. Psychological effects were considered the primary outcome, whilst physical condition was secondary. RESULTS: Four subjects were lost and twenty-three were analyzed. General linear model with 2 criteria revealed significant changes (p = 0.05) in trait anxiety symptoms over time in the low-to-moderate intensity group (LMIG). Within group changes followed a significant decrease in levels of anxiety (38.82 ± 2.20 to 33.36 ± 2.83, p = 0.004) and depression (10.36 ± 2.83 to 6.73 ± 1.88, p = 0.006) related symptoms amongst those in the LMIG. INTERPRETATION: This study indicated that depression and anxiety symptoms were reduced amongst a non-clinical sample of Primary educated pre-adolescents when they were subject to a low-to-moderate exercise program. The program focused on associating movement with pleasure, encouraged positive and non-competitive interactions between participants. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, identifier NCT02970825, autumn 2016, updated May 7, 2018 (https://clinicaltrials.gov/ct2/show/NCT02970825).

12.
Neuroimage Clin ; 17: 325-334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29159044

RESUMO

INTRODUCTION: Since we recently showed in behavioural tasks that the top-down cognitive control was specifically altered in tinnitus sufferers, here we wanted to establish the link between this impaired executive function and brain alterations in the frontal cortex in tinnitus patients. METHOD: Using functional magnetic resonance imaging (fMRI), we monitored the brain activity changes in sixteen tinnitus patients (TP) and their control subjects (CS) while they were performing a spatial Stroop task, both in audition and vision. RESULTS: We observed that TP differed from CS in their functional recruitment of the dorsolateral prefrontal cortex (dlPFC, BA46), the cingulate gyrus and the ventromedial prefrontal cortex (vmPFC, BA10). This recruitment was higher during interference conditions in tinnitus participants than in controls, whatever the sensory modality. Furthermore, the brain activity level in the right dlPFC and vmPFC correlated with the performance in the Stroop task in TP. CONCLUSION: Due to the direct link between poor executive functions and prefrontal cortex alterations in TP, we postulate that a lack of inhibitory modulation following an impaired top-down cognitive control may maintain tinnitus by hampering habituation mechanisms. This deficit in executive functions caused by prefrontal cortex alterations would be a key-factor in the generation and persistence of tinnitus.


Assuntos
Função Executiva/fisiologia , Córtex Pré-Frontal/fisiopatologia , Zumbido/fisiopatologia , Zumbido/psicologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico , Teste de Stroop , Adulto Jovem
13.
Eur J Neurosci ; 45(11): 1439-1450, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27471102

RESUMO

Hearing a beat recruits a wide neural network that involves the auditory cortex and motor planning regions. Perceiving a beat can potentially be achieved via vision or even touch, but it is currently not clear whether a common neural network underlies beat processing. Here, we used functional magnetic resonance imaging (fMRI) to test to what extent the neural network involved in beat processing is supramodal, that is, is the same in the different sensory modalities. Brain activity changes in 27 healthy volunteers were monitored while they were attending to the same rhythmic sequences (with and without a beat) in audition, vision and the vibrotactile modality. We found a common neural network for beat detection in the three modalities that involved parts of the auditory dorsal pathway. Within this network, only the putamen and the supplementary motor area (SMA) showed specificity to the beat, while the brain activity in the putamen covariated with the beat detection speed. These results highlighted the implication of the auditory dorsal stream in beat detection, confirmed the important role played by the putamen in beat detection and indicated that the neural network for beat detection is mostly supramodal. This constitutes a new example of convergence of the same functional attributes into one centralized representation in the brain.


Assuntos
Percepção Auditiva , Putamen/fisiologia , Percepção do Tato , Percepção Visual , Adulto , Humanos
14.
Front Syst Neurosci ; 10: 75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27625596

RESUMO

Over the last decade, functional brain imaging has provided insight to the maturation processes and has helped elucidate the pathophysiological mechanisms involved in brain plasticity in the absence of vision. In case of congenital blindness, drastic changes occur within the deafferented "visual" cortex that starts receiving and processing non visual inputs, including olfactory stimuli. This functional reorganization of the occipital cortex gives rise to compensatory perceptual and cognitive mechanisms that help blind persons achieve perceptual tasks, leading to superior olfactory abilities in these subjects. This view receives support from psychophysical testing, volumetric measurements and functional brain imaging studies in humans, which are presented here.

15.
PLoS One ; 10(3): e0120387, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25763867

RESUMO

Tinnitus is the perception of sound in the absence of external stimulus. Currently, the pathophysiology of tinnitus is not fully understood, but recent studies indicate that alterations in the brain involve non-auditory areas, including the prefrontal cortex. In experiment 1, we used a go/no-go paradigm to evaluate the target detection speed and the inhibitory control in tinnitus participants (TP) and control subjects (CS), both in unimodal and bimodal conditions in the auditory and visual modalities. We also tested whether the sound frequency used for target and distractors affected the performance. We observed that TP were slower and made more false alarms than CS in all unimodal auditory conditions. TP were also slower than CS in the bimodal conditions. In addition, when comparing the response times in bimodal and auditory unimodal conditions, the expected gain in bimodal conditions was present in CS, but not in TP when tinnitus-matched frequency sounds were used as targets. In experiment 2, we tested the sensitivity to cross-modal interference in TP during auditory and visual go/no-go tasks where each stimulus was preceded by an irrelevant pre-stimulus in the untested modality (e.g. high frequency auditory pre-stimulus in visual no/no-go condition). We observed that TP had longer response times than CS and made more false alarms in all conditions. In addition, the highest false alarm rate occurred in TP when tinnitus-matched/high frequency sounds were used as pre-stimulus. We conclude that the inhibitory control is altered in TP and that TP are abnormally sensitive to cross-modal interference, reflecting difficulties to ignore irrelevant stimuli. The fact that the strongest interference effect was caused by tinnitus-like auditory stimulation is consistent with the hypothesis according to which such stimulations generate emotional responses that affect cognitive processing in TP. We postulate that executive functions deficits play a key-role in the perception and maintenance of tinnitus.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Zumbido/fisiopatologia , Percepção Visual/fisiologia , Estimulação Acústica , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Restor Neurol Neurosci ; 33(1): 67-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25420904

RESUMO

PURPOSE: Tinnitus is the perception of a sound in the absence of external stimulus. Currently, the pathophysiology of tinnitus is not fully understood, but recent studies indicate that alterations in the brain involve non-auditory areas, including the prefrontal cortex. Here, we hypothesize that these brain alterations affect top-down cognitive control mechanisms that play a role in the regulation of sensations, emotions and attention resources. METHODS: The efficiency of the executive control as well as simple reaction speed and processing speed were evaluated in tinnitus participants (TP) and matched control subjects (CS) in both the auditory and the visual modalities using a spatial Stroop paradigm. RESULTS: TP were slower and less accurate than CS during both the auditory and the visual spatial Stroop tasks, while simple reaction speed and stimulus processing speed were affected in TP in the auditory modality only. CONCLUSIONS: Tinnitus is associated both with modality-specific deficits along the auditory processing system and an impairment of cognitive control mechanisms that are involved both in vision and audition (i.e. that are supra-modal). We postulate that this deficit in the top-down cognitive control is a key-factor in the development and maintenance of tinnitus and may also explain some of the cognitive difficulties reported by tinnitus sufferers.


Assuntos
Percepção Auditiva/fisiologia , Transtornos Cognitivos/etiologia , Detecção de Sinal Psicológico/fisiologia , Zumbido/complicações , Percepção Visual/fisiologia , Estimulação Acústica , Adulto , Idoso , Análise de Variância , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Tempo de Reação , Percepção Espacial/fisiologia , Inquéritos e Questionários , Escala Visual Analógica , Adulto Jovem
17.
Cereb Cortex ; 25(8): 2035-48, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24518755

RESUMO

Early blindness results in both structural and functional changes of the brain. However, these changes have rarely been studied in relation to each other. We measured alterations in cortical thickness (CT) caused by early visual deprivation and their relationship with cortical activity. Structural and functional magnetic resonance imaging was performed in 12 early blind (EB) humans and 12 sighted controls (SC). Experimental conditions included one-back tasks for auditory localization and pitch identification, and a simple sound-detection task. Structural and functional data were analyzed in a whole-brain approach and within anatomically defined regions of interest in sensory areas of the spared (auditory) and deprived (visual) modalities. Functional activation during sound-localization or pitch-identification tasks correlated negatively with CT in occipital areas of EB (calcarine sulcus, lingual gyrus, superior and middle occipital gyri, and cuneus) and in nonprimary auditory areas of SC. These results suggest a link between CT and activation and demonstrate that the relationship between cortical structure and function may depend on early sensory experience, probably via selective pruning of exuberant connections. Activity-dependent effects of early sensory deprivation and long-term practice are superimposed on normal maturation and aging. Together these processes shape the relationship between brain structure and function over the lifespan.


Assuntos
Percepção Auditiva/fisiologia , Cegueira/patologia , Cegueira/fisiopatologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Estimulação Acústica , Adulto , Idade de Início , Envelhecimento/patologia , Envelhecimento/fisiologia , Cegueira/diagnóstico por imagem , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal , Testes Neuropsicológicos , Tamanho do Órgão , Oxigênio/sangue , Tomografia Computadorizada por Raios X
18.
Perception ; 43(10): 1083-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25509685

RESUMO

Although early blind (EB) individuals are thought to have a better musical sense than sighted subjects, no study has investigated the musical rhythm and beat processing abilities in EB individuals. Using an adaptive 'up and down' procedure, we measured the beat asynchrony detection threshold and the duration discrimination threshold, in the auditory and vibrotactile modalities in both EB and sighted control (SC) subjects matched for age, gender, and musical experience. We observed that EB subjects were better than SC in the beat asynchrony detection task; that is, they showed lower thresholds than SC, both in the auditory and in the vibrotactile modalities. In addition, EB subjects had a lower threshold than SC for duration discrimination in the vibrotactile modality only. These improved beat asynchrony detection abilities may contribute to the known excellent musical abilities often observed in many blind subjects.


Assuntos
Percepção Auditiva/fisiologia , Cegueira/psicologia , Discriminação Psicológica/fisiologia , Estimulação Física/métodos , Percepção do Tempo/fisiologia , Percepção do Tato/fisiologia , Estimulação Acústica/métodos , Adulto , Idade de Início , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Música
19.
Behav Brain Res ; 269: 147-54, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24793493

RESUMO

Tinnitus can be defined as the perception of noxious disabling internal sounds in the absence of external stimulation. While most individuals with tinnitus show some habituation to these internal sounds, many of them experience significant daily life impairments. There is now convincing evidence that impairment in attentional processes may be involved in tinnitus, particularly by hampering the habituation mechanism related to the prefrontal cortex activity. However, it is thus still unclear whether this deficit is an alteration of alerting and orienting attentional abilities, or the consequence of more general alteration in the executive control of attention. In the present study, 20 tinnitus patients were compared to 20 matched healthy controls using the Attention Network Test, to clarify which attentional networks, among alerting, orienting, and executive networks, show differences between the groups. The results showed that patients with tinnitus do not present a general attentional deficit but rather a specific deficit for top-down executive control of attention. This deficit was highly correlated with patient characteristics of years of tinnitus duration and the frequency of coping strategies employed to alleviate tinnitus distress in daily life. These findings are discussed in terms of recent neurobiological models suggesting that prefrontal cortex activity might especially be related to tinnitus habituation. Therapeutic perspectives focusing both on rehabilitation of the executive control of attention and neuromodulation are also discussed.


Assuntos
Atenção , Função Executiva , Zumbido/psicologia , Percepção Visual , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Testes Neuropsicológicos , Estimulação Luminosa , Córtex Pré-Frontal/fisiopatologia , Tempo de Reação , Inquéritos e Questionários , Zumbido/fisiopatologia , Adulto Jovem
20.
Neurosci Biobehav Rev ; 41: 53-63, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23453908

RESUMO

The "neural Darwinism" theory predicts that when one sensory modality is lacking, as in congenital blindness, the target structures are taken over by the afferent inputs from other senses that will promote and control their functional maturation (Edelman, 1993). This view receives support from both cross-modal plasticity experiments in animal models and functional imaging studies in man, which are presented here.


Assuntos
Cegueira/fisiopatologia , Córtex Cerebral/fisiopatologia , Plasticidade Neuronal/fisiologia , Percepção/fisiologia , Animais , Humanos
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