Postural control characterization according to age and auditory input in cochlear implant users.

Aims/Objectives: Understand the relationship between auditory input and balance motor control. Material and Methods: Twelve prelingual adolescent cochlear implant users (CIU) and 12 adult postlingual CIU were tested by posturography on a force platform with eyes open in two conditions, with the cochlear implant (CI) on and off. Energy consumption (EC) of the body center of pressure sway signal was measured, calculating total EC and divided into three bands of frequencies; low (B1) 0-0.1 Hz, medium (B2) 0.1-1 Hz, and high (B3)1-2 Hz. Wilcoxon and Mann-Whitney tests were used for statistical analysis and the significance level was P ≤ 0.05. Results: Prelingual CIU decrease the EC in low and high frequencies throughout the adolescence (P < 0.05) assessed with the CI turned on, while it did not show any modification with the CI off. Postlingual CIU showed a deterioration of PR related to aging when evaluated with the CIU turned off, P < 0.05 in band 1. However, with the CI turned on they had no significant increase in this age range. Conclusions and Significance: The acoustic input improved EC of postural responses in higher and lower frequencies in adolescence and with aging which suggests a relationship with gross and fine movements involved in postural control.

Motor and cognitive performances in pre-lingual cochlear implant adolescents, related with vestibular function and auditory input.

BACKGROUND: Information about the role of auditory input and motor control is limited. OBJECTIVES: Assessment the relationship between auditory and vestibular information with specific motor and cognitive functions. METHODS: Posturography in 17 Pre-lingual Cochlear Implant Adolescents, (PCIA) age 14.06 ± 3.05 in four sensory conditions was analyzed: (A) eyes open, cochlear implant (CI) on, (B) eyes open, CI off, (C) eyes closed standing on a foam over a platform (ECFP) with CI on, and (D) ECFP, CI off. Gait velocity (GV) was registered by inertial sensors using a 10-meter test. Vestibulo-ocular reflex (VOR) was evaluated with the video head impulse test (VHIT) and visual spatial skill (VS) assessed with the WISC-V test. RESULTS: SV had no significant difference between conditions A and B (p = .2461). Comparing C and D, SV values decreased when CI was turned on (p = .0036). A significant linear relationship between VOR and GV (p = .0064) generating the VOR gain loss lower gait. Relationship between VOR and VS scores was no significant (p = .685). CONCLUSIONS AND SIGNIFICANCE: Auditory information is a relevant cue when somatosensory and visual inputs are modified and range of vestibular function influence in a dynamic motor activity as gait, facts which must be considered in the neurodevelopment control.

Sensorimotor interaction in deaf children. Relationship between gait performance and hearing input during childhood assessed in pre-lingual cochlear implant users.

CONCLUSIONS: The results suggest that auditory input is not neutral in motor skills and the complex interaction between them is generated in the earlier stages of childhood development. Objective The assessment of gait performance in pre-lingual deaf children with cochlear implant (CI). METHODS: Gait velocity (GV), using a 10-meter test, was measured by means of three inertial sensors in 10 pre-lingual cochlear implant users (CIU) (10-16 years old) in three sensory conditions: (1) cochlear implant turned on with environmental noise (EN), (2) cochlear implant turned on with EN and with cognitive dual task (DT), and (3) CI turned off (CI-OFF). GV with EN and DT was assessed in a normal hearing control group (CG) (n = 14). Mann-Whitney and Wilcoxon Signed ranked test were used for significance validation. RESULTS: (1) GV in CG was lower in DT than with EN (p = .019). (2) GV was faster in CG with EN compared with the three conditions in CIU (EN, p = .006; DT, p = .0001; CI-OFF, p = .03). (3) CIU had slower GV walking with EN (p = .037) and with DT (p = .022). (4) Dividing the CIU sample by age, the acoustic information generates a slower gait for those implanted after 3 years old.

Postural responses applied in a control model in cochlear implant users with pre-lingual hearing loss.

Conclusions The assessment of postural responses (PR) based in a feedback control system model shows selective gains in different bands of frequencies adaptable with child development. Objective PR characterization of pre-lingual cochlear implant users (CIU) in different sensory conditions. Methods Total energy consumption of the body's center of pressure signal (ECCOP) and its distribution in three bands of frequencies: band 1 (0-0.1 Hz), band 2 (0.1-0.7 Hz), and band 3 (0.7-20 Hz) was measured in a sample of 18 CIU (8-16 years old) and in a control group (CG) (8-15 years old). They were assessed in a standing position on a force platform in two sensory conditions: 1 = Eyes open. 2 = Eyes closed and standing on foam. Results In condition 1, total ECCOP of PR and its proportion of energy consumption in the three bands of frequencies were similar between CIU and CG (p > 0.05). In condition 2, CIU have significantly higher ECCOP, mainly in high frequencies (bands 2 and 3) (p < 0.05). ECCOP values decreased with age also, mainly in bands 2 and 3. This behavior is interpreted in the control system model proposed as an adaptation process related with child development.

Chronic balance disorders after acoustic neuroma surgery: assessment of gravitational vertical perception.

CONCLUSION: The head tilt response (HTR) test performed in a group of patients with chronic dizziness after acoustic neuroma surgery showed alterations in the gravitational vertical perception (GV). OBJECTIVE: The assessment of the accuracy in the GV through the HTR test in patients with long-term balance disorders after acoustic neuroma surgery. METHODS: The HTR was performed in two groups of patients that had undergone acoustic neuroma surgery: six uncompensated patients (UPs) who maintained vestibular symptoms 1 year after surgery and two compensated patients (CPs) without vestibular symptoms. Twelve healthy control adults were also tested (control group, CG). Three parameters were measured in the HTR test: steady-state error (SSE), rise time (TRS), and mean energy of the error signal per step (MEE). RESULTS: The UP group showed higher values for the TRS and MEE parameters compared with the CG (p < 0.05) when performing the HTR test to the side of the lesion and to the contralateral side, while the SSE only showed significant higher values when the patient estimated the GV towards the side of the lesion. The two patients in the CP group did not have differences in the three parameters assessed when compared with the CG.

Postural response characterization in elderly patients with bilateral vestibular hypofunction.

CONCLUSIONS: The measurement of the energy consumption (EC) of the body's center of pressure (COP) to maintain the upright stance position was higher in elderly patients with bilateral vestibular hypofunction (BVH) compared with a control group and may be a valid parameter in the assessment of balance disorders. OBJECTIVE: The aim of the study was to evaluate the energy consumption of the COP in elderly patients with BVH. METHODS: The COP was recorded on a force platform (FP) for eight elderly patients with BVH related to aging and eight normal control group subjects. The EC of the COP was calculated using the discrete wavelet transform. The two groups were tested in standing position on the FP in three sensory conditions:1, eyes open; 2, eyes closed; and 3, standing on a foam pad placed on the force platform. Wilcoxon's rank test and multi-factor analysis of variance were used, with the level of significance set at 0.05. RESULTS: BVH patients showed higher values of EC of the COP signal measured in arbitrary units compared with the control group (conditions 1 and 2). None of the BVH patients could perform the test in condition 3. BVH patients had increased EC in the frequency band between 0.1 and 0.78 Hz when the visual information was canceled (condition 2).

Balance in Parkinson's disease patients changing the visual input.

The description of the postural responses in Parkinson's disease patients when visual information changes from a stable to a moving visual field analyzing the impact on balance in these patients. METHODS (CLINICAL): Limits of Stability, Body center of pressure and balance functional reserve were measured by means of the force platform in 24 Parkinson's patients in stages 1 and 2 of the Boher classification and 19 volunteers as a control group. Both groups were stimulated with 1-Static visual field and 2-horizontal optokinetic stimulation using a virtual reality system. Postural responses were analyzed using the inverted pendulum as mathematical model. RESULTS: While the control group didn't show significant differences on the postural control between the two sensory conditions (COP p=0.0017, BFR p=0.0025), Parkinson's patients presented significant differences in the area of the center of pressure and the balance functional reserve values between static visual field and optokinetic stimulation. (COP p=0.0017, BFR p=0.0025). CONCLUSIONS: The results support the hypothesis about the influence of the changes in the visual information in triggering balance control disorders in Parkinson's patients. It is discussed the interest of these fact in the assessment and the rehabilitation programs of this disease.

Balance in Parkinson's disease patients changing the visual input / Equilíbrio na doença de Parkinson alterando as informações visuais

The description of the postural responses in Parkinson's disease patients when visual information changes from a stable to a moving visual field analyzing the impact on balance in these patients. METHODS (CLINICAL): Limits of Stability, Body center of pressure and balance functional reserve were measured by means of the force platform in 24 Parkinson´s patients in stages 1 and 2 of the Boher classification and 19 volunteers as a control group. Both groups were stimulated with 1-Static visual field and 2-horizontal optokinetic stimulation using a virtual reality system. Postural responses were analyzed using the inverted pendulum as mathematical model. RESULTS: While the control group didn't show significant differences on the postural control between the two sensory conditions (COP p=0.0017, BFR p=0.0025), Parkinson's patients presented significant differences in the area of the center of pressure and the balance functional reserve values between static visual field and optokinetic stimulation. (COP p=0.0017, BFR p=0.0025). CONCLUSIONS: The results support the hypothesis about the influence of the changes in the visual information in triggering balance control disorders in Parkinson's patients. It is discussed the interest of these fact in the assessment and the rehabilitation programs of this disease.

Descrição das respostas posturais em pacientes com doença de Parkinson quando a informação visual muda de um campo visual estável para um móvel, analisando o impacto do equilíbrio nesses pacientes. MÉTODOS (CLÍNICO): Limites de estabilidade, centro de pressão corporal e reserva funcional do equilíbrio foram medidos em uma plataforma de força em 24 pacientes com doença de Parkinson nos estágios 1 e 2 da classificação de Boher e em 19 voluntários de um grupo controle. Ambos os grupos foram estimulados a partir de um campo visual estático e dois estímulos optocinéticos horizontais, usando-se um sistema de realidade virtual. As respostas posturais foram analisadas usando-se o pêndulo invertido como modelo matemático. RESULTADOS: Enquanto o grupo controle não demonstrou diferenças significativas no controle postural entre as duas condições sensoriais (COP p=0,0017, BFR p=0,0025), os pacientes com doença de Parkinson apresentaram diferenças significativas na área do centro de pressão e nos valores de reserva do equilíbrio funcional entre o campo visual estático e a estimulação optocinética (COP p=0,0017, BFR p=0,0025). CONCLUSÕES: Os resultados corroboram a hipótese sobre a influência das mudanças na informação visual deflagrando distúrbios no controle do equilíbrio em pacientes com doença de Parkinson. Discutimos esse fato com relação à avaliação e programas de reabilitação associados a essa doença.