Effects of a multi‐session cognitive training combined with brain stimulation on age‐associated cognitive decline

Abstract

AbstractBackgroundResearch on non‐invasive methods of modulating age‐associated cognitive decline has yielded promising results. Current evidence shows that transcranial direct current stimulation (tDCS), if administered with concurrent cognitive training, may successfully modulate cognitive performance. In the TrainStim‐Cog trial, we investigated in healthy older adults if longer‐term training combined with tDCS, versus sham, would lead to higher increases in performance on the trained tasks, and to larger transfer to non‐trained domains. Moreover, we aimed to elucidate neural mechanisms underlying these effects.MethodFifty‐six participants (20 men; mean age / SD = 69.8 / 4.0 yrs) underwent nine sessions of cognitive training over a period of three weeks with concurrent administration of either tDCS stimulation over 20 min (1mA current) or sham stimulation. The cognitive training consisted of two tasks targeting executive functions: a letter‐updating task was used to train working memory updating and, reward‐based decision‐making was trained with a three‐stage Markov decision‐making task. Prior to the intervention and immediately after the intervention, performance on training and transfer tasks was assessed and neural correlates were recorded using structural, functional and diffusion tensor MRI.ResultAt the time of submitting this abstract, assessment of primary endpoint has just been completed; data base lock, and unblinding of intervention type will be conducted in February 2020. The trial has been registered at clinicaltrials.gov (ID NCT03838211), the study protocol of the trial has been published (Antonenko et al., 2019, Frontiers in Aging Neuroscience), and a statistical analysis plan has been uploaded at clinicaltrials.gov. Results of the analyses will be presented at the AAIC conference.ConclusionOur results will determine if a 3‐week combined cognitive training and tDCS approach may not only enhance trained functions, but also transfer to non‐trained tasks. Moreover, we will determine if effects are sustained over longer periods of time, and we will aim to identify predictors of response to the intervention on the individual level. Thus, our trial will hopefully contribute to the development of non‐medical interventions in the field of age‐associated cognitive decline.