Modulating Prospective Memory in Older Adults With Noninvasive Brain Stimulation
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 106
- 试验地点
- 1
- 主要终点
- Executive controlling functioning
研究概览
简要总结
Prospective memory is the ability to remember to carry out intentions with a certain delay (e.g. remember to buy stamps when passing a postal office). Prospective memory tasks require a large degree of self-initiated retrieval and in the absence of a prompt to recall, people must 'remember to remember' by their own volition. Thus, prospective memory is a challenge - especially in old age with increasing health-related prospective memory demands.
Previous studies reported links between neural activity in specific brain regions and prospective memory performance. Yet, the mere occurrence of a change in brain activity in concomitance with performance of a behavioral task is not sufficient to confirm a causal relationship between the two phenomena. Therefore, this study aims to apply non-invasive brain stimulation to facilitate or inhibit activity in different brain regions presumed to be functionally associated with prospective memory. Additional to the prospective memory tasks, the investigators will implement control tasks (i.e., attention) to assess whether stimulation will specifically enhance prospective memory performance or whether other cognitive functions will be modulated additionally.
It is hypothesized that stimulation will lead to changes in prospective memory functioning. Further, the investigators expect that facilitation of attentional processes might be linked to prospective memory improvements.
详细描述
This study aims to modulate neural activity in the left and right inferior frontal lobe as well as in the right superior parietal lobe via high-definition transcranial direct current stimulation (HD-tDCS) in older adults. There is evidence from functional magnetic resonance imaging (fMRI) studies that these areas are involved in prospective memory performance in younger and older adults but a causal relation between activity in these areas and responses in prospective memory tasks has not been established so far.
A double blind, sham-controlled, parallel group design will be applied. Healthy older adults (n=105) will participate in two separate sessions: During the first baseline session, no stimulation is applied. For the second session, participants will then be randomly assigned to one of seven experimental groups (cathodal vs. anodal right inferior frontal lobe (rIFL); cathodal vs. anodal left inferior frontal lobe (lIFL); cathodal vs. anodal right superior parietal lobe (rSPL); or sham). Real stimulation will be applied during 20 minutes with one Milliamp (mA). In case of sham stimulation (i.e., control intervention), the electrode positions and the attachment procedures correspond to those of real tDCS but the electrical current will only be ramped up to one mA and switched off completely after 30 s of stimulation.
The primary objective of this study is the modulation of prospective memory performance in a computer-based task via tDCS. Further, this study aims to clarify the role of attentional control for prospective memory performance, as both processes seem to recruit similar neural structures. Additionally, naturalistic and self-rated prospective memory performance will be assessed.
It is hypothesized that stimulation of the right inferior frontal lobe will lead to changes in prospective memory performance and attentional processes. Whether cathodal or anodal stimulation will enhance performance is not clear yet, since previous fMRI studies were inconsistent about activity changes in older adults. Further, the investigators expect that anodal stimulation of the left inferior frontal cortex may lead to faster responses to prospective memory stimuli, whereas cathodal stimulation of the same area may lead to prolonged reaction times. It is hypothesized that attentional control will not be affected by stimulation of the left inferior frontal lobe. Finally, the investigators expect that anodal stimulation of the right superior parietal cortex will lead to better prospective memory and attentional control performance, whereas cathodal stimulation will have detrimental effects on both functions.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 60 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •No cognitive impairments
- •Fluent in German
- •Right-handed
- •Normal or corrected-to-normal vision
- •Non-smokers
- •Written informed consent
排除标准
- •Current/lifetime severe psychiatric or neurological disorder
- •Metal implants in the head area
- •Psychotropic medication
- •Dermatosis
- •Current/lifetime alcohol abuse
- •Magnetisable implants
研究组 & 干预措施
anodal stimulation of the rIFL
Anodal stimulation over the right inferior frontal lobe
干预措施: Non-invasive brain stimulation (Device)
cathodal stimulation of the rIFL
Cathodal stimulation over the right inferior frontal lobe
干预措施: Non-invasive brain stimulation (Device)
anodal stimulation of the lIFL
Anodal stimulation over the left inferior frontal lobe
干预措施: Non-invasive brain stimulation (Device)
cathodal stimulation of the lIFL
Cathodal stimulation over the left inferior frontal lobe
干预措施: Non-invasive brain stimulation (Device)
anodal stimulation of the rSPL
Anodal stimulation over the right superior parietal lobe
干预措施: Non-invasive brain stimulation (Device)
cathodal stimulation of the rSPL
Cathodal stimulation over the right superior parietal lobe
干预措施: Non-invasive brain stimulation (Device)
sham stimulation
Sham stimulation over either of the three real stimulation areas
干预措施: Sham stimulation (Device)
结局指标
主要结局
Executive controlling functioning
时间窗: During both sessions (for stimulation session: during intervention), task fixed to 6 minutes
Assessed with a computer task (ANT - Attentional Network Task). Interference between answers given to congruent and incongruent stimuli. Change from baseline to intervention session, difference between intervention groups.
Inhibition reaction time
时间窗: During both sessions (for stimulation session: directly after intervention), 2 minutes
Assessed with a go/no-go computer task (TAP -Test of Attentional Performance). Mean/ median of reactions times to correct responses. Change from baseline to intervention session, difference between intervention groups.
Prospective memory reaction time
时间窗: During both sessions (for stimulation session: during intervention), fixed to 14 minutes
Assessed with a computer task. Reaction times of answers given to prospective memory stimuli. Change from baseline to intervention session, difference between intervention groups.
Flexibility reaction-time
时间窗: During both sessions (for stimulation session: directly after intervention), 3 minutes
Assessed with a computer task (TAP - Test of Attentional Performance). Mean/ median of reactions times of correct responses. Change from baseline to intervention session, difference between intervention groups.
Divided attention reaction time
时间窗: During both sessions (for stimulation session: directly after stimulation), 3 minutes 30 seconds
Assessed with a computer-based task (Test of Attentional Performance). Median reaction time of correct answers. Change from baseline to intervention session, difference between intervention groups.
Prospective memory performance
时间窗: During both sessions (for stimulation session: during intervention), fixed to 14 minutes
Assessed with a computer task. Number of correct answers given to prospective memory stimuli. Change from baseline to intervention session, difference between intervention groups.
Inhibition errors
时间窗: During both sessions (for stimulation session: directly after intervention), 2 minutes
Assessed with a computer task (Test of Attentional Performance). Sum of incorrect responses to no-go stimuli. Change from baseline to intervention session, difference between intervention groups.
Flexibility performance
时间窗: During both sessions (for stimulation session: directly after intervention), 3 minutes
Assessed with a computer task (TAP- Test of Attentional Performance). Number of correct answers. Change from baseline to intervention session, difference between intervention groups.
Divided attention misses
时间窗: During both sessions (for stimulation session: directly after intervention), 3 minutes 30 seconds
Assessed with a computer task (TAP - Test of Attentional Performance). Sum of missed target stimuli. Change from baseline to intervention session, difference between intervention groups.
次要结局
- Orienting network functioning(During both sessions (for stimulation session: during intervention), task fixed to 6 minutes)
- Alerting network functioning(During both sessions (for stimulation session: during intervention), task fixed to 6 minutes)
- Ongoing-task performance(During both sessions (for stimulation session: during intervention), fixed to 14 minutes)
- Ongoing-task reaction time(During both sessions (for stimulation session: during intervention), fixed to 14 minutes)
- Ongoing-task intra-individual coefficient of variation(During both sessions (for stimulation session: during intervention), fixed to 14 minutes)