NCT05937022

The Effects of Transcranial Direct Current Stimulation (tDCS) in Older Lonely Individuals

Utilizing Transcranial Direct Current Stimulation (tDCS) to Boost Social Pleasure and Participation in Older Lonely Individuals

• Status: Unknown
• Phase: N/A
• Study type: Interventional
• Enrollment: 135 (estimated)
• Sponsor: The University of Hong Kong · Academic / Other
• Sex: All
• Age: 60 Years
• Healthy volunteers: Accepted

Summary

This randomized clinical trial aims to test the effects of 10 sessions of transcranial direct current stimulation (tDCS) on social and emotional functions in lonely older adults. The main objectives include: * Understand whether tDCS could successfully boost positive social processing and social motivation in older adults, paralleling its effect on non-social reward processing; * Understand whether the reduced negative and increased positive social processing in older adults would translate to an increase in real-life social activity and a decrease in loneliness feeling; * Examine the intervention efficacy of tDCS among the aged population; * Understand whether the tDCS effect could be long-lasting (i.e., 1 and 3 months after intervention). Participants will be lonely older adults aged 60 or above and screened on inclusion and exclusion criteria. Eligible participants will be randomly allocated to the left dorsolateral prefrontal cortex (DLPFC) tDCS group, the right ventrolateral prefrontal cortex (VLPFC) tDCS group, or the sham control group. Participants will complete an Emotion Rating Task, questionnaires assessing their psychosocial functions, and neuropsychological tests assessing their cognitive functions at baseline, after the 5th stimulation session, immediately after the 10th stimulation session, and 1 month and 3 months after the 10th stimulation session.

Detailed description

Loneliness, or perceived social isolation, results from discrepancies between an individual's desired and achieved social needs. A substantial proportion of older adults experience loneliness. With the social distancing policies implemented during the COVID-19 pandemic, older adults, who are more likely to be functionally dependent on their caregivers, have been primarily affected, contributing to adverse impacts on their social and emotional functions. As current loneliness interventions have shown limited efficacy, it is of great significance to test novel interventions for lonely older adults. Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that has demonstrated its safety and efficacy in modulating cortical excitability and associated behaviors in older adults. It has been suggested that repeated tDCS sessions show sustained therapeutic efficacy in chronic disorders. Additionally, the efficacy of tDCS as an intervention for lonely older adults has not been investigated. As a result, it is crucial to test repeated tDCS sessions as a potential intervention to reduce loneliness and improve socioemotional functions in lonely older adults.

Conditions

• Loneliness

Interventions

Type	Name	Description
DEVICE	Experimental Transcranial Direct Current Stimulation (tDCS)	This study will deliver tDCS sessions for ten sessions completed within two weeks. Consecutive tDCS sessions are separated by at least 24 hours. Participants assigned to one of the two experimental groups will receive 20 minutes of active stimulation with a 2mA intensity over the corresponding brain regions.
DEVICE	Sham Transcranial Direct Current Stimulation (tDCS)	This study will deliver tDCS sessions for ten sessions completed within two weeks. Consecutive tDCS sessions are separated by at least 24 hours. Participants assigned to the sham control group will receive 30 seconds of active stimulation over brain regions identical to either the left DLPFC or the right VLPFC experimental tDCS group.

Timeline

• Start date: 2022-12-03
• Primary completion: 2024-12-01
• Completion: 2025-12-01
• First posted: 2023-07-10
• Last updated: 2023-07-12

Locations

1 site across 1 country: Hong Kong