Effects of tDCS on Social Cognition in Aging (SoCoStim)

University Medicine Greifswald

Status: Completed

Conditions: Aging; Social Cognition

Treatments: Behavioral: Social Cognition Task; Device: tDCS

Study type: Interventional

Funder types: Other

Identifiers

NCT04633499

SoCoStim

Details and patient eligibility

About

The aim of the study is to explore the effect of transcranial direct current stimulation (tDCS) on either the right tempo-parietal junction (rTPJ) or the dorsomedial prefrontal cortex (dmPFC) in healthy older adults (replication in a different sample of a study by Martin et al., 2020).

Full description

Humans are fundamentally social animals. The ability to operate within large social networks requires considerable cognitive capacity, often referred to as social cognition. One social cognitive process thought to involve embodied and nonembodied processes is perspective-taking. Recently, the right temporoparietal junction (rTPJ) has been suggested as a key hub for embodied processing relevant to social cognition. A study of Martin et al. (2020) could further provide causal evidence that the right temporoparietal junction is involved specifically in the embodied component of perspective-taking. Specifically, HD-tDCS (high-definition transcranial direct current stimulation) to the right temporoparietal junction, but not another hub of the social brain (dorsomedial PFC), increased the effect of body position during perspective-taking, but not tracking. As social cognition is affected by the aging process and decline of socio-cognitive abilities is a key feature of neurological diseases such as Alzheimer's or Parkinson's disease, the aim of the present study is to replicate the findings of Martin et al., (2020) in a sample of healthy older adults to better understand the modulation of socio-cognitive processes in older age.

The aim of the study is to explore the effect of transcranial direct current stimulation (tDCS) on either the right tempo-parietal junction (rTPJ) or the dorsomedial prefrontal cortex (dmPFC) in healthy older adults (replication in a different sample of a study by Martin et al., 2020). 60 healthy older adults and 30 younger participants (serving as a control group) will be tested in a Reading the Eyes in the Mind Task (RMET) and a Task of Visual Perspective Taking (VPT) , while stimulation either the rTPJ or the dmPFC with either active or sham tDCS (stimulation only in the group of older participants). In the RMET the expectation is that older participants have higher reaction times after correct answers under rTPJ tDCS. No stimulation effects of the dmPFC are expected. In the VPT older participants are expected to have a selective effect on body position (similar to the results of Martin et al., 2020) under rTPJ stimulation, but not dmPFC stimulation.

A further focus of the study is how functional and structural connectivity of the brain and individual differences measured with an MRI assessment influence with the success of the RMET and VPT paradigms in an explorative research question.

Enrollment: 90 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• healthy older (60 - 80 years) and younger (18 - 30 years) participants
• German as their main language or sufficient german skills to understand the experiment and the task

Exclusion criteria

• participants with neuropsychological or psychiatric disease that affect cognition.
• standard MRI exclusion criteria (e.g. pregnancy, metal implants)
• standard tDCS exclusion criteria (e.g. metal implants in the head)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

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90 participants in 3 patient groups

dmPFC tDCS + Social Cognition tasks in older participants

Active Comparator group

Description:

Participants will receive either active or sham stimulation over the dmPFC while conducting two different social cognition paradigms: one regarding emotion recognition, one on visual perspective taking.

Treatment:

Device: tDCS

Behavioral: Social Cognition Task

rTPJ tDCS + Social Cognition tasks in older participants

Experimental group

Description:

Participants will receive either active or sham stimulation over the rTPJ while conducting two different social cognition paradigms: one regarding emotion recognition, one on visual perspective taking.

Treatment:

Device: tDCS

Behavioral: Social Cognition Task

Social cognition tasks in younger participants

Active Comparator group

Description:

Participants will conduct two different social cognition paradigms: one regarding emotion recognition, one on visual perspective taking but without tDCS stimulation.

Treatment:

Behavioral: Social Cognition Task