2026 ECNP Congress

EP01-1069

tDCS and working memory training to improve cognitive function in patients with mild Alzheimer’s dementia and mild cognitive impairment

Monica Cornea — C. Bacila · Dr. Gheorghe Preda Clinical Hospital of Psychiatry- Sibiu, Neuroscience Research Center, Sibiu, Romania

2026 ECNP Congress

Background

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia worldwide, significantly impacting patients and caregivers. [1] It is characterized by a gradual decline in cognitive functions, including memory, language, attention, and executive functioning. Mild cognitive impairment (MCI) is considered an intermediate stage between normal aging and dementia, often representing a prodromal phase of AD. [2] Early intervention during this stage may delay or prevent progression to dementia. In recent years, non-pharmacological approaches such as transcranial direct current stimulation (tDCS) and cognitive training (CT) have gained attention for their potential to enhance cognitive functioning. Working memory training (WMT), a subtype of CT, specifically targets attention and short-term memory processes. [3,4]

Aims

This study aims to evaluate the efficacy of combined tDCS and WMT in improving cognitive functions, particularly working memory and attention, in individuals diagnosed with AD or MCI.

Methods

This study is designed as a prospective, experimental, parallel, sham-controlled trial including 80 participants aged over 60 years, recruited from a clinical psychiatric hospital. Participants will be allocated into two groups: an intervention group receiving active tDCS combined with WMT (n=40) and a control group receiving sham tDCS with WMT (n=40). The intervention will be administered over a 2-week period, with sessions conducted 5 days per week, lasting 30 minutes each.

Active tDCS will be delivered at an intensity of 2 mA for 30 minutes, targeting the dorsolateral prefrontal cortex (DLPFC) using electrodes positioned at F3 and F4 according to the EEG 10–20 system. Sham stimulation will replicate the initial sensation of tDCS but will cease after 30 seconds. During stimulation, participants will simultaneously engage in WMT tasks delivered via tablet-based applications, including digit span (forward and backward) and visual matching exercises.

Cognitive performance will be assessed using the Montreal Cognitive Assessment (MoCA) and the Alzheimer’s Disease Assessment Scale–Cognitive Subscale (ADAS-Cog 11) at baseline, immediately post-intervention, and at 4- and 8-week follow-ups.

Hypotheses: We hypothesize that (1) frontal tDCS will enhance working memory and attention; (2) the combination of tDCS and WMT will yield greater cognitive improvements compared to sham stimulation; and (3) these improvements will be sustained over time, particularly in individuals with MCI.

Expected Results: We expect that participants in the intervention group will show significant improvements in attention and memory performance compared to the control group. These improvements are anticipated to persist at 4-week follow-up in both AD and MCI groups, while at 8 weeks, sustained benefits are expected primarily in the MCI group, with some decline in AD patients. Minimal or no improvements are expected in the control group.

Conclusions

This study may provide evidence for the synergistic effects of tDCS and WMT as effective non-pharmacological interventions for cognitive enhancement in AD and MCI, potentially contributing to delaying cognitive decline and improving quality of life.

Keywords: Alzheimer’s disease, mild cognitive impairment, tDCS, working memory training, cognitive intervention

References

  1. WHO. Dementia: Global action plan on the public health response to dementia 2017 -2025. Dementia. 2020
  2. Breijyeh, Z.; Karaman, R. Comprehensive Review on Alzheimer’s Disease: Causes and Treatment. Molecules 2020, 25.
  3. Lefaucheur, J.P., Antal, A., Ayache, S. S., Benninger, D. H., Brunelin, J., Cogiamanian F., Cotelli, M., De Ridder, D., Ferrucci, R., Langguth, B., Marangolo, P., Mylius, V., A. Nitsche, A. M., Padberg, F, Palm, U., Poulet,E., Priori,A., Rossi, S., Schecklmann, M., Vanneste, S., Ziemann, U., Garcia-Larrea,L., Paulus, W., Evidence-based guidelines on the therapeutic use of transcranial direct current stimulation (tDCS), Clinical Neurophysiology, 2017, 128.
  4. Wenqi, W., Jiaming, L., Jiang, X. ,Tingfei, Z.,Yuxing, Z., Jiayu,W., Shulin, C.,. The Transfer Effects of Cognitive Training on Working Memory Among Chinese Older Adults With Mild Cognitive Impairment: A Randomized Controlled Trial, Frontiers in Aging Neuroscience, 2019, 11