Brain Stimulation for Foot-sole Sensation in Older Adults With Foot-sole Somatosensory Deficits

ConditionsSomatosensory Function Balance Control Mobility

Trial statusRecruiting

Trial phaseNot applicable

Trial typeInterventional

Biological sexAll

Age65+

SponsorHebrew SeniorLife

About this trial

In older adults, diminished sensation of the legs and feet is highly prevalent and causes poor balance and reduced mobility. This type of sensation is not only dependent upon the receptors and nerves in the legs and feet, but also upon a complex central nervous system pathway that includes the cerebral cortex of the brain. This project will use a form of noninvasive brain stimulation called transcranial direct current stimulation (tDCS) to test whether increasing the excitability of the brain networks that process sensory feedback can augment foot sole sensation, balance, and mobility in older adults suffering from mild-to-moderate foot sole sensory impairments.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Aged ≥65 years.

Self-reported feeling of unsteadiness or difficulty when standing and walking.

Mild-to-moderate foot-sole somatosensory impairment: the ability to perceive 75g monofilament but inability to perceive 10g monofilament.

Disqualifiers

self-reported inability to stand or walk continuously for one minute without personal assistance (canes or walkers allowed);

history or presence of foot ulceration, amputation, or deformities;

self-reported uncontrolled pain or pain that is associated with mobility disability;

uncontrolled diabetes mellitus;

Trial design

Design model

Crossover

Treatments tested in this trial

transcranial direct current stimulation
Device
tDCS can safely and selectively modulate cortical excitability (specifically neuronal firing likelihood) by transferring weak electrical currents between scalp electrodes. The direct current delivered by any one electrode will not exceed 2.0 mA and the total amount of current from all electrodes will not exceed 4 mA in this study.
active sham stimulation
Device
sham stimulation will implement the same protocol of the tDCS intervention; however, only very low-level currents (no more than 0.5 mA) are transferred between the same electrodes used for the tDCS throughout the 20-minute session. This strategy effectively mimics the cutaneous sensations and skin redness induced by creating only micro cortical electric fields.

Treatment groups

20 Participants

are divided into 2 treatment groups

Group A: tDCS groupExperimental treatment 1 intervention

Group B: sham groupSham comparator 1 intervention

Trial outcomes

Primary outcomes

postural sway area when standing with eyes closed on the foam

This metric assesses the degree to which the soft support and cut-off of the vision diminishes the control of standing posture.

Time frame