Elderly Idiopathic Fallers Clinical Trial
Official title:
The Effect of Transcranial Direct Current Stimulation (tDCS) on Motor and Cognitive Functions in Idiopathic Fallers
The concurrent performance of two tasks, i.e., dual tasking (DT), is a common and ubiquitous
every day phenomena. For example, people frequently walk while talking on a cellphone or
drive while talking to a passenger. Often, the performance of one or more of these
simultaneously performed tasks may deteriorate when another task is carried out at the same
time, even in healthy young adults. This reduction in performance is referred to as the DT
deficit or DT cost and is typically much higher in Idiopathic Fallers (IF) than in
age-matched controls. In this population the DT cost impairs the gait pattern, as
manifested, for example, in increased gait variability, exacerbating instability and fall
risk.
In the proposed study, would be evaluated the effects of tDCS on dual tasking performance
following tDCS.
The researchers expect that stimulation of the Pre Frontal Cortex (PFC) (using tDCS) will
increase DT performance and prefrontal activation.
tDCS intervention: Noninvasive tDCS will be delivered by study personnel uninvolved with any
other study procedures. In the study will be used a battery-driven electrical stimulator.
Stimulation and sham condition will be performed based on previous studies. Briefly, the
anode will be placed over the PFC and the cathode over the right supraorbital region. The
real tDCS condition will consist of 20 min of continuous stimulation at target intensity of
1.5 mA. This amount of stimulation is safe for healthy young and older adults and has been
shown to induce acute beneficial changes in cortical excitability and cognitive functions.
For the sham condition, an inactive stimulation protocol would be followed, as compared with
an 'off-target' active protocol, in order to minimize participant risk.
Pre- and post-tDCS assessments will include:
Gait assessment: Gait parameters will include both spatial and temporal parameters obtained
using body fixed wearable sensors (accelerometers and gyroscopes) [Weiss et al. 2015; Ben et
al. 2015]. Parameters will include (but are not limited to) gait speed, stride length and
stride time as well as rhythmicity measures such as stride to stride variability and gait
regularity.
Fall history and fear of falling will also be assessed (e.g., Falls Efficacy Scale
International, FES-I) to further characterize the cohort and explore possible confounds.
Cognitive assessment: A detailed computerized cognitive battery that has been used
extensively at TASMC in different cohorts [Dwolatzky et al. 2003;Hausdorff et al.
2006;Springer et al. 2006;Yogev et al. 2005;Aarsland et al. 2003] will quantify several
cognitive domains including working memory, executive function, verbal function, problem
solving, a global cognitive score, and attention.
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