Cognitive Training and Brain Stimulation in Women With Post-chemotherapy Cognitive Impairment

Study Overview
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Brief Summary
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The aim of this study is to investigate whether a high definition tDCS-accompanied intensive cognitive training of working memory leads to performance improvement in women with post-chemotherapy cognitive impairment after breast cancer treatment.

Detailed Description
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Patients who have undergone chemotherapy, may develop post-chemotherapy cognitive impairment (PCCI), which may occur in several cognitive domains and persist for many years. These declines in cognitive functions can lead to psychological distress and affect overall patients' quality of life. The goal of the present study is to assess behavioral effects of a multi-session cognitive training combined with high-definition transcranial direct current stimulation (tDCS) in women with PCCI. First studies have shown positive effects of cognitive training on trained and untrained functions and the subjective perception of stress, however the effects are small and transfer effects are inconsistent. A promising approach to elongate and increase the effects of cognitive training is to combine the training with tDCS. Therefore, in this study women with PCCI will participate in a three-week cognitive training with concurrent online high-definition tDCS application. Cognitive performance (primary), as well as Quality of Life scores and Sleep data 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. A Follow-up session to assess long-term effects is planned four weeks after the post assessment. The results of the study will offer valuable insights into efficacy of combined tDCS and cognitive training intervention in women with PCCI in order to establish its potential to induce improvements in cognitive functions, and to beneficially affect patient-reported outcome measures.

Official Title
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Neuromodulation Through Brain Stimulation-assisted Cognitive Training in Patients With Post-chemotherapy Cognitive Impairment

Conditions
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Breast Cancer, Cognitive Impairment

Intervention / Treatment
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* Device: Anodal tDCS
* Device: Sham tDCS
* Behavioral: Intensive cognitive training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chemotherapy to treat breast cancer (≥ 6 months post-treatment). Self-reported concerns regarding cognitive functioning. Age: 18-60 years. Exclusion Criteria: History of dementia before treatment of cancer. Other neurodegenerative neurological disorders; epilepsy or history of seizures. Severe and untreated medical conditions that preclude participation in the training, as determined by responsible physician. History of moderate to severe substance use disorder according to DSM-5 Moderate to severe acute psychiatric disorders according to DSM-5 Contraindication to tDCS application (Antal et al., 2017)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: stimulation group<br>Anodal tDCS+ intensive cognitive Training | Device: Anodal tDCS<br>* Anodal transcranial direct current stimulation (tDCS), 9 sessions with 20 minutes stimulation each (2 mA).<br>Behavioral: Intensive cognitive training<br>* Intensive cognitive training of a letter memory updating task, 9 sessions for approximately 20 min<br>|
| Sham Comparator: sham group<br>Sham tDCS + intensive cognitive Training | Device: Sham tDCS<br>* Sham transcranial direct current stimulation (tDCS), 9 sessions with 30 sec stimulation each (2 mA) to ensure blinding of participants.<br>Behavioral: Intensive cognitive training<br>* Intensive cognitive training of a letter memory updating task, 9 sessions for approximately 20 min<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Working memory performance at post-assessment | Performance in a near transfer task (n-back) under anodal tDCS compared to sham condition; operationalized by % correct responses in the n-back task | 3 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Working memory performance at follow-up assessment | Performance in a near transfer task (n-back) under anodal tDCS compared to sham condition; operationalized by % correct responses in the n-back task | 4 weeks after training | 
| Working memory training performance (Letter Updating Task) at post-assessment | Performance in primary memory training task (Letter Updating Task) at post-assessment, operationalized by number of correctly recalled lists in the letter updating task | 3 weeks | 
| Working memory training performance (Letter Updating Task) at follow-up assessment | Performance in primary memory training task (Letter Updating Task) at follow-up assessment, operationalized by number of correctly recalled lists in the letter updating task | 4 weeks after training | 
| Quality of Life at post-assessment | PROMIS score for HRQoL (PROPr score) and scores of subscales (e.g. cognitive function) | 3 weeks | 
| Quality of Life at follow-up assessment | PROMIS score for HRQoL (PROPr score) and scores of subscales (e.g. cognitive function) | 4 weeks after training | 
| Visuo-spatial performance at post-assessment | Visuo-spatial performance at post-assessment operationalized by number of correctly recalled items in the VR task. | 3 weeks | 
| Visuo-spatial performance at follow-up assessment | Visuo-spatial performance at follow-up assessment operationalized by number of correctly recalled items in the VR task. | 3 weeks |