Final Report Summary - NEUROCOGPLASTICITY (Neurocognitive Plasticity – Lifespan Mechanisms of Change)
The aim of NeuroCogPlasticity was to uncover mechanisms governing neurocognitive plasticity – its potentials, restrictions and time course, in young and old age. To address this aim, we studied healthy younger (age 20-30 years) and older (age 70-80 years) adults across time periods within which they either engaged in a program involving memory training or a systematic cognitive activity not involving memory specifically, or they were not engaged in any systematic cognitive program. All participants underwent repeated testing with standardized as well as experimental cognitive tests and brain scanning with magnetic resonance imaging. These methods yield rich information on baseline as well as changes in cognition and brain structure and activity. We developed and solidified cognitive programs, and studied potential, specificity, and restrictions of cognitive plasticity in younger and older age. We found evidence for cognitive plasticity in terms of positive changes in episodic memory with training both in younger and older age. While the cognitive benefits of training generally were larger in younger than older adults, there was marked variability of the extent of plastic response in older age. We found that certain brain characteristics before start of training, such as the microstructure of the brain’s white matter, could be used to predict how well participant would respond to training. This was found for older participants. We also found that the training intervention itself affected white matter microstructure in older adults, and the amount of microstructural change was related to the amount of improvement in memory function during the course of the intervention. However, after the training period ended, some of these structural brain effects were reduced. We specifically addressed the temporal dynamics of WM plasticity, by studying changes over repeated periods of training and rest. The general decline in WM microstructure observed across the duration of the study was moderated following the training periods, demonstrating that cognitive training may mitigate age-related brain deterioration. The training-related improvements were estimated to subside over time, indicating that continuous training may be a premise for the enduring attenuation of neural decline. Continued and challenging cognitive tasks seem to be a premise for sustain effects of cognitive interventions on brain structure.