Transcranial direct current stimulation enhances foot sole somatosensation when standing in older adults.
Exp Brain Res
; 236(3): 795-802, 2018 03.
Article
en En
| MEDLINE
| ID: mdl-29335751
ABSTRACT
Foot-sole somatosensation is critical for safe mobility in older adults. Somatosensation arises when afferent input activates a neural network that includes the primary somatosensory cortex. Transcranial direct current stimulation (tDCS), as a strategy to increase somatosensory cortical excitability, may, therefore, enhance foot-sole somatosensation. We hypothesized that a single session of tDCS would improve foot-sole somatosensation, and thus mobility, in older adults. Twenty healthy older adults completed this randomized, double-blinded, cross-over study consisting of two visits separated by one week. On each visit, standing vibratory threshold (SVT) of each foot and the timed-up-and-go test (TUG) of mobility were assessed immediately before and after a 20-min session of tDCS (2.0 mA) or sham stimulation with the anode placed over C3 (according to the 10/20 EEG placement system) and the cathode over the contralateral supraorbital margin. tDCS condition order was randomized. SVT was measured with a shoe insole system. This system automatically ramped up, or down, the amplitude of applied vibrations and the participant stated when they could or could no longer feel the vibration, such that lower SVT reflected better somatosensation. The SVTs of both foot soles were lower following tDCS as compared to sham and both pre-test conditions [F(1,76) > 3.4, p < 0.03]. A trend towards better TUG performance following tDCS was also observed [F(1,76) = 2.4, p = 0.07]. Greater improvement in SVT (averaged across feet) moderately correlated with greater improvement in TUG performance (r = 0.48, p = 0.03). These results suggest that tDCS may enhance lower-extremity somatosensory function, and potentially mobility, in healthy older adults.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Postura
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Umbral Sensorial
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Corteza Somatosensorial
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Percepción del Tacto
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Estimulación Transcraneal de Corriente Directa
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Pie
Tipo de estudio:
Clinical_trials
Límite:
Aged
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Humans
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Middle aged
Idioma:
En
Revista:
Exp Brain Res
Año:
2018
Tipo del documento:
Article
País de afiliación:
Estados Unidos