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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.
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.

3.
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
4.
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.

5.
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).

6.
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
7.
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
8.
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.

9.
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
10.
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
11.
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
12.
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
13.
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
14.
Front Psychol ; 4: 663, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24151473

RESUMO

In number comparison tasks, the performance is better when the distance between the numbers to compare increases. It has been shown that this so-called numerical distance effect (NDE) decreases with age but the neuroanatomical correlates of these age-related changes are poorly known. Using functional magnetic resonance imaging (fMRI), we recorded the brain activity changes in children aged from 8 to 14 years while they performed a number comparison task on pairs of Arabic digits and a control color comparison task on non-numerical symbols. On the one hand, we observed developmental changes in the recruitment of frontal regions and the left intraparietal sulcus (IPS), with lower activation as age increased. On the other hand, we found that a behavioral index of selective sensitivity to the NDE was positively correlated with higher brain activity in a right lateralized occipito-temporo-parietal network including the IPS. This leads us to propose that the left IPS would be engaged in the refinement of cognitive processes involved in number comparison during development, while the right IPS would underlie the semantic representation of numbers and its activation would be mainly affected by the numerical proximity between them.

15.
PLoS One ; 8(8): e71907, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23967263

RESUMO

Using functional magnetic resonance imaging (fMRI) in ten early blind humans, we found robust occipital activation during two odor-processing tasks (discrimination or categorization of fruit and flower odors), as well as during control auditory-verbal conditions (discrimination or categorization of fruit and flower names). We also found evidence for reorganization and specialization of the ventral part of the occipital cortex, with dissociation according to stimulus modality: the right fusiform gyrus was most activated during olfactory conditions while part of the left ventral lateral occipital complex showed a preference for auditory-verbal processing. Only little occipital activation was found in sighted subjects, but the same right-olfactory/left-auditory-verbal hemispheric lateralization was found overall in their brain. This difference between the groups was mirrored by superior performance of the blind in various odor-processing tasks. Moreover, the level of right fusiform gyrus activation during the olfactory conditions was highly correlated with individual scores in a variety of odor recognition tests, indicating that the additional occipital activation may play a functional role in odor processing.


Assuntos
Cegueira/fisiopatologia , Lobo Occipital/fisiologia , Odorantes , Percepção Olfatória/fisiologia , Estimulação Acústica , Adulto , Comportamento/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
16.
Behav Res Methods ; 42(4): 1072-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21139174

RESUMO

We describe the development and evaluation of a computer-controlled system for delivering odors in a magnetic resonance imaging (MRI) environment. The system allows a timely presentation of different odors in synchrony with MRI sequences and participant's inspiration phase. The rise/fall time of odor deliverance has been optimized to generate prompt and strong stimulations. Equipped with a user-friendly programming interface, the system can be used reliably in a wide range of experimental paradigms. We have paid particular attention to developing a portable system that is relatively easy, rapid, and inexpensive to replicate. The equipment has been tested in a 3-Tesla MRI in a boxcar paradigm, in which stimulation conditions alternated with rest periods (no stimulation). The experiment demonstrated the good functioning of the device and its efficiency in producing the expected activation in the olfactory cortex; it also revealed some methodological and technical aspects to be improved.


Assuntos
Automação Laboratorial/instrumentação , Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Odorantes , Percepção Olfatória/fisiologia , Mapeamento Encefálico , Humanos , Processamento de Imagem Assistida por Computador
17.
Neuroreport ; 21(17): 1069-73, 2010 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-20881509

RESUMO

It has been shown that the volume of the olfactory bulb (OB) changes with function. The aim of this study was to investigate whether the OB volume and the olfactory function in early blind (EB) subjects increase compared with controls. Psychophysical testing of olfactory performances and OB volumetric measurements assessed by an MRI scan were studied. Quantitative olfactory function expressed in the odor discrimination and odor-free identification scores was higher in EB subjects compared with controls. The mean of right, left and total OB volume was 65.40, 75.48, and 140.89 mm, respectively for the EB subjects and 54.47, 52.11, and 106.60 mm, respectively for the controls, with these differences being significant. EB subjects have superior olfactory abilities and presented with significantly higher OB volume than the sighted controls. OB plasticity may explain this compensatory mechanism between visual deprivation and enhanced olfactory perception.


Assuntos
Cegueira/fisiopatologia , Plasticidade Neuronal/fisiologia , Bulbo Olfatório/crescimento & desenvolvimento , Bulbo Olfatório/patologia , Olfato/fisiologia , Adulto , Cegueira/patologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Hipertrofia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Bulbo Olfatório/fisiopatologia , Tamanho do Órgão/fisiologia , Fatores de Tempo , Adulto Jovem
18.
Neuron ; 68(1): 138-48, 2010 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-20920797

RESUMO

The occipital cortex (OC) of early-blind humans is activated during various nonvisual perceptual and cognitive tasks, but little is known about its modular organization. Using functional MRI we tested whether processing of auditory versus tactile and spatial versus nonspatial information was dissociated in the OC of the early blind. No modality-specific OC activation was observed. However, the right middle occipital gyrus (MOG) showed a preference for spatial over nonspatial processing of both auditory and tactile stimuli. Furthermore, MOG activity was correlated with accuracy of individual sound localization performance. In sighted controls, most of extrastriate OC, including the MOG, was deactivated during auditory and tactile conditions, but the right MOG was more activated during spatial than nonspatial visual tasks. Thus, although the sensory modalities driving the neurons in the reorganized OC of blind individuals are altered, the functional specialization of extrastriate cortex is retained regardless of visual experience.


Assuntos
Cegueira/patologia , Lobo Occipital/fisiopatologia , Localização de Som/fisiologia , Percepção Espacial/fisiologia , Estimulação Acústica/métodos , Adulto , Análise de Variância , Cegueira/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Lobo Occipital/irrigação sanguínea , Oxigênio/sangue , Tato/fisiologia
19.
Disabil Rehabil Assist Technol ; 5(3): 175-83, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20214472

RESUMO

AIM: Sensory substitution (SS) represents a unique opportunity to provide congenitally blind persons with visual-like experience. Although visual experience influences the way we perceive the external world, little is known about the effects of SS experience. PURPOSE: To investigate the effects of perceptual experience (visual versus sensory substitution) on depth perception through an SS system, object localization abilities of early blind (n = 10), and blindfolded sighted control subjects (n = 20) were assessed before and after a practicing period with a visual-to-auditory SS device. METHOD: During the pre- and post-test, subjects had to replace, by hand, an object previously localized using the device. The practicing phase consisted of three sessions during which subjects tried to localize and grasp an object using the device. Results. At the pre-test, sighted subjects spontaneously used efficiently different pictorial depth cues to estimate object distance while the blind subjects were affected by their lack of visual experience and were significantly less accurate. Post-test showed that the brief practicing phase sufficed to enable blind subjects to acquire the rules of visual depth and to use them efficiently with the device. CONCLUSIONS: These results suggest the possibility to compensate for some effects of early and long-lasting blindness by providing visual-like experience via SS. Theoretical implications are discussed.


Assuntos
Cegueira/congênito , Cegueira/terapia , Percepção de Profundidade , Auxiliares Sensoriais , Percepção Visual , Adaptação Fisiológica , Adulto , Fatores Etários , Análise de Variância , Cegueira/reabilitação , Auxiliares de Comunicação para Pessoas com Deficiência , Percepção de Distância , Feminino , Humanos , Masculino , Fatores de Tempo
20.
Can J Exp Psychol ; 63(4): 287-93, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20025387

RESUMO

Congenital blindness is one of the rare human models to explore the role of experience-driven cross-modal compensation after early sensory deprivation. We re-examined spatial attention abilities in congenitally blind participants and sighted controls using a paradigm comparable to the one of our previous study (Collignon, Renier, Bruyer, Tranduy, & Veraart, 2006), except that this time the auditory and tactile stimuli were now presented in sequence. Although both groups performed the task with similar accuracy, we observed that blind participants had shorter reaction times than sighted controls for the detection of spatial targets in both sensory modalities. Moreover, this finding held true for both the selective and divided attention conditions. These results not only confirm previous reports on the superiority of the blind during auditory and tactile attention tasks, but also broaden our knowledge of the mechanisms underlying cross-modal compensation.


Assuntos
Percepção Auditiva/fisiologia , Cegueira/congênito , Cegueira/fisiopatologia , Tempo de Reação/fisiologia , Tato/fisiologia , Estimulação Acústica/métodos , Adulto , Análise de Variância , Comportamento de Escolha/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Limiar Sensorial/fisiologia , Percepção Espacial , Adulto Jovem
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