Healthy Older Adults
Conditions
Brief summary
The goal of this clinical trial is to investigate the acute effects of immersive virtual reality (VR)-based exergaming combined with transcranial direct current stimulation (tDCS) on executive functions in healthy older adults. The main questions it aims to answer are: * Does VR-based exergaming combined with tDCS improve executive function performance in healthy older adults compared with a control condition? * Do single interventions (tDCS alone or VR-based exergaming alone) improve executive function performance compared with the control condition? * Does the combined intervention produce greater improvements in executive function performance than either intervention alone? Researchers will compare four intervention conditions to evaluate differences in executive function performance following each session. Participants will: * Complete four intervention sessions in a randomized crossover sequence, with a washout period of at least 7 days between sessions * Receive the following intervention conditions: * sham-tDCS + VR-video * tDCS + VR-video * sham-tDCS + VR-exergaming * tDCS + VR-exergaming * Complete executive function assessments immediately after each session, including: * the Flanker task for inhibitory control * the more-odd shifting task for cognitive flexibility * the Corsi block-tapping task for working memory
Interventions
The anodal electrode is positioned over the left DLPFC (F3), and the cathodal electrode is placed over the right supraorbital area. The transcranial direct current stimulation is applied for 20 min at an intensity of 2 mA, with 15 s ramp-up and 15 s ramp-down.
The anodal electrode is positioned over the left DLPFC (F3), and the cathodal electrode is placed over the right supraorbital area. Sham stimulation is applied in the same locations for 20 min with only 15s ramp-up and 15s ramp-down stimulation to mimic the sensory experience of real stimulation.
For the VR-exergaming condition, participants engage in an interactive rhythm-based fitness game called PowerBeatsVR. It immerses participants in a virtual exercise environment accompanied by dynamic musical beats, with punching and tracking movements. The VR-exergaming consisted of four cycles of 3.5 min, each separated by a 2-min rest interval, for a total duration of 20 min
For the VR-video condition, participants view a mild plant documentary called Journey of Chinese Plants through the same VR headset. VR-video intervention consisted of four cycles of 3.5 min, each separated by a 2-min rest interval, for a total duration of 20 min
Sponsors
Study design
Eligibility
Inclusion criteria
(1) Age between 60 to 70 years old; (2) Right-handed (Edinburgh Handedness Inventory (Chinese version) \> 40); (3) Normal overall cognitive function (Montreal Cognitive Assessment (Beijing version) ≥ 26).
Exclusion criteria
(1) Musculoskeletal injury; (2) neurological/neurodegenerative disorders (e.g., Alzheimer's disease); (3) history of brain infections or cerebrovascular diseases; (4) psychiatric disorders (e.g., major depressive disorder, schizophrenia); (5) unstable or chronic medical conditions (e.g., cardiac disease, seizures (personal/family history)); (6) hearing and visual impairments (e.g., color blindness and conditions severely affecting the ability to see the screen or distinguish colors); (7) metal implants (e.g., pacemakers); (8) brain stimulation or exercise training intervention within the past 6 months; (9) failure to meet safety criteria for brain stimulation (e.g., pregnancy)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Reaction time and accuracy of inhibitory control are assessed by the Flanker task. | Immediately after the intervention. |
Secondary
| Measure | Time frame |
|---|---|
| Reaction time and accuracy of cognitive flexibility are assessed by more odds shifting task. | Immediately after the intervention. |
| Scores of working memory are assessed by the Corsi Block-Tapping Task | Immediately after the intervention. |