The goal of this randomised controlled trial is to investigate the effects of a 2-week high-frequency transcranial pulsed current stimulation (tPCS) on cognitive outcomes in older and healthy adults. The main questions it aims to answer are:
1. Would a single session of anodal tPCS over the left prefrontal cortex improve working memory, task inhibition, and task switching in healthy young and older adults, compared to anodal transcranial direct current stimulation (tDCS) and sham-tPCS? 2. Would repeated session of anodal-tPCS (2-weeks) lead to improvements in working memory, task inhibition, and task switching in healthy young and older adults, compared to tDCS and sham-tPCS? 3. Will tPCS be better tolerated among healthy adults, compared to tDCS?
Researchers will compare tPCS / tDCS / sham-tPCS to see if there are any differences in cognitive outcomes after 1 session and after repeated sessions, as well as to compare the tolerance of tPCS against tDCS and sham-tPCS.
Participants will be requested to:
* Undergo 1 of 3 of the following conditions: tDCS / tPCS / sham-tPCS * Complete three sessions of cognitive tasks testing working memory, inhibition and task switching at baseline (pre-stimulation), after day 1 of brain stimulation and after 10 sessions of brain stimulation (post- repeated stimulation) * Undergo fNIRS-EEG brain measurements concurrently with the cognitive tasks
Male and female young (21 to 30 years) and older adults (60 to 75 years)
Right-handed
Must be a native English speaker
No clinical diagnosis of neurodevelopmental, mood, neurological or neurodegenerative disorders
Currently on long-term medication for pain or migraines / headaches
Adults with metallic implants in the chest or head region
Adults with epilepsy, or known seizure or immediate family members that have had a seizure before
Had a recent head injury that resulted in a temporary loss of consciousness or of memory in the last 12 months
Nanyang Technological University
Lead sponsor
Ministry of Education, Singapore
Collaborator
National Institute of Education, Singapore
Collaborator