AUTHOR=Esteves Madalena , Magalhães Ricardo , Marques Paulo , Castanho Teresa C. , Portugal-Nunes Carlos , Soares José M. , Almeida Armando , Santos Nadine C. , Sousa Nuno , Leite-Almeida Hugo TITLE=Functional Hemispheric (A)symmetries in the Aged Brain—Relevance for Working Memory JOURNAL=Frontiers in Aging Neuroscience VOLUME=10 YEAR=2018 URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2018.00058 DOI=10.3389/fnagi.2018.00058 ISSN=1663-4365 ABSTRACT=

Functional hemispheric asymmetries have been described in different cognitive processes, such as decision-making and motivation. Variations in the pattern of left/right activity have been associated with normal brain functioning, and with neuropsychiatric diseases. Such asymmetries in brain activity evolve throughout life and are thought to decrease with aging, but clear associations with cognitive function have never been established. Herein, we assessed functional laterality during a working memory task (N-Back) in a healthy aging cohort (over 50 years old) and associated these asymmetries with performance in the test. Activity of lobule VI of the cerebellar hemisphere and angular gyrus was found to be lateralized to the right hemisphere, while the precentral gyrus presented left > right activation during this task. Interestingly, 1-Back accuracy was positively correlated with left > right superior parietal lobule activation, which was mostly due to the influence of the left hemisphere. In conclusion, although regions were mostly symmetrically activated during the N-Back task, performance in working memory in aged individuals seems to benefit from lateralized involvement of the superior parietal lobule.