Clinical trial NCT04265378: Cognitive Training and Brain Stimulation in Prodromal Alzheimer's Disease
Official title: Effects of Cognitive Training and Brain Stimulation in Prodromal Alzheimer's Disease - Randomised, Sham Controlled, Interventional Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Subjective Cognitive Decline
Mild Cognitive Impairment
Keywords: memory
brain stimulation
Lead sponsor: University Medicine Greifswald
Sponsor class: OTHER
First posted: 2020-02-11
Enrollment: 46
Sex: ALL
Minimum age (years): 60
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The aim of this study is to investigate whether a tDCS-accompanied intensive cognitive training of working memory leads to performance improvement in individuals with prodromal Alzheimer's disease.

Detailed description: The goal of the present study is to assess behavioral (primary) effects of a multi-session cognitive training combined with transcranial direct current stimulation (tDCS). Many studies to date have found tDCS to be an efficient method to enhance various cognitive functions by modulating cortical excitability in young adults, but its behavioral impact and underlying mechanisms in pathological aging still need to be elucidated. Individuals with prodromal Alzheimer's disease, will participate in a three-week cognitive training with concurrent online tDCS application. Cognitive performance (primary) will be examined before, during and after the intervention, in order to draw conclusions about the effect of tDCS. In addition to cognitive training, a control group, receiving sham stimulation during training, will be assessed. Follow-up sessions to assess long-term effects are planned four weeks and seven months after the post assessment. Furthermore, to assess potential predictors of tDCS effects, functional and structural parameters will be measured with MRI. The results of the study will offer valuable insights into efficacy of combined tDCS and cognitive training, as compared to training alone, in individuals with prodromal stages of Alzheimer's disease. Moreover, improved understanding of tDCS effects on cognitive training performance and underlying neural correlates may help to develop novel approaches for modulating cognitive decline in healthy and pathological aging.

Eligibility criteria: Inclusion Criteria:

* Older adults (60 - 80 years);
* Right handedness;
* subjective cognitive decline (SCD) or mild cognitive impairment (MCI)

Exclusion Criteria:

* Dementia or other neurodegenerative neurological disorders; epilepsy or history of seizures; close relatives with epilepsy or history of seizures; previous stroke;
* Severe and untreated medical conditions that precludes participation in the training, as determined by responsible physician;
* History of severe alcoholism or use of drugs;
* Severe psychiatric disorders such as depression (if not in remission) or psychosis

Primary outcomes:
measure: Working memory training performance (Letter Updating task)
timeFrame: 3 weeks
Secondary outcomes:
measure: Working memory training performance (Markov task)
timeFrame: 3 weeks
measure: Transfer outcomes: numerical n-back task (% correct)
timeFrame: 3 weeks
measure: Transfer outcomes: AVLT (auditory verbal learning test) (sum of correctly recalled items trials 1-5)
timeFrame: 3 weeks
measure: Transfer outcomes: Wiener Matrices Test (no. correct)
timeFrame: 3 weeks
measure: Long-term outcomes: Letter Updating task (no. of correctly recalled lists)
timeFrame: 4 weeks and 7 months after training
measure: Long-term outcomes: Markov decision making task (% optimal actions)
timeFrame: 4 weeks and 7 months after training
measure: Long-term outcomes: numerical n-back task (% correct)
timeFrame: 4 weeks and 7 months after training
measure: Long-term outcomes: AVLT (auditory verbal learning test) (sum of correctly recalled items trials 1-5)
timeFrame: 4 weeks and 7 months after training
measure: Long-term outcomes: Wiener Matrices Test (no. correct)
timeFrame: 4 weeks and 7 months after training
measure: Neural correlates: Structural neural correlates of tDCS effect
timeFrame: before training; 7 months after training
measure: Neural correlates: Functional neural correlates of tDCS effect
timeFrame: before training; 7 months after training
Other outcomes:
Locations:
city: Greifswald
country: Germany
facility: University Medicine Greifswald
Study officials:
References:
citation: Thams F, Kuzmina A, Backhaus M, Li SC, Grittner U, Antonenko D, Floel A. Cognitive training and brain stimulation in prodromal Alzheimer's disease (AD-Stim)-study protocol for a double-blind randomized controlled phase IIb (monocenter) trial. Alzheimers Res Ther. 2020 Nov 7;12(1):142. doi: 10.1186/s13195-020-00692-5.