Are two interventions are better than one? Combining cognitive training and non-invasive neurostimulation in older adults.

Introduction, Rationale & Novelty
Age-related cognitive decline presents an ever increasing challenge and public health issue. It can have a significant impact both an individuals' and their families' quality of life (QoL). Interventions which enhance the brain's natural ability to modify/restructure neural connections have been shown to enhance cognitive functioning, in both individuals with Mild Cognitive Impairment (MCI) and healthy older adults.

Both cognitive training and neurostimulation interventions results are promising, demonstrating enhancement of cognitive function. However, direct evidence is needed to determine whether the success is 'domain-specific' or whether benefits are carried over to other cognitive demands and daily events, using Activities in Daily Living Measures (ADL). As people with MCI and their families have rated QoL as the principal factor they wish to foster, there is a need to investigate how interventions impact on QoL as an outcome measure in addition to cognitive and neural effects.

Research aims:
1. Acceptability and feasibility using cognitive training intervention combined with neurostimulation within the ageing population.
2. Gather initial data on the effect of intervention on putative Electroencephalography (EEG) biomarkers.
3. Gather initial data assessing whether the effect of combined cognitive and neurostimulation interventions is greater than either intervention alone.

This project addresses methodological gaps and provides a comprehensive account of cognitive training and its mechanism in older adults by combining complementary techniques: non-invasive neurostimulation, EEG and QoL questionnaires. We expect that both interventions will increase cognitive function and quality of daily life, with those participants in the combined intervention demonstrating the greatest improvement.

Method

The Memory Alteration Test will be used to assess cognitive function/MCI classification. In line with previous research, ~60 participants (aged 70+) will be recruited.
Participants will complete the following tasks before and after intervention: working/episodic/verbal memory tasks, visual-attention, processing speed, executive function, a QoL Questionnaire, Hospital Anxiety and Depression Score and an Activities of Daily Living Assessment. Participants will be randomly allocated to one of three conditions.

Experimental Group Intervention Treatment Group Control Group
Group 1 (n=20) Cognitive Intervention alone: 15 sessions of Computer-Assisted Cognitive Training
Group 2 (n=20) Neurostimulation alone: 15 sessions of tACS
Group 3 (n=20) Combined Cognitive Intervention and Neurostimulation: 15 sessions of tACS, concurrent with a cognitive training task

A 'Computer-Assisted Cognitive Training' (Cambridge Cognition Systems) intervention will be used and completed on iPad/computer software. Transcranial Alternating Current Stimulation (tACS) will be used for non-invasive electrical stimulation. tACS uses low level alternating currents applied via scalp electrodes to specific brain regions. As neural oscillations play a crucial role in the operational architecture of the brain, tACS may prove even more effective in enhancing cognitive functions. EEG will be acquired before and after cognitive training.
20 participants with MCI will receive cognitive training combined with neurostimulation protocol. Their results will be compared to the same intervention in age-matched controls. This will be a pilot study for feasibility of using our protocol in clinical populations.

Impact
This project furthers the understanding of successful ageing within social and biological sciences and contributes towards interventions that improve the lives of older adults and their families, reducing pressures on the healthcare system. The project will specifically emphasise improvements to QoL by targeting the deficits in cognitive decline which individuals are most aware of.