Effects of Ai-Chi Practice on Balance and Left Cerebellar Activation during High Working Memory Load Task in Older People: A Controlled Pilot Trial Author: Michal Nissim1,2, Abigail Livny3,4,5, Caroline Barmatz1,3, Galia Tsarfaty1,3, Yitshal Berner1, Yaron Sacher1, Raffaella Bodini3, Navah Z Ratzon1 Affiliation: <sup>1</sup> Sackler Faculty of Medicine, School of Health Professions, Tel Aviv University, Tel-Aviv P.O. Box 39040, Israel. <sup>2</sup> The David Yellin Academic College of Education, Teachers for Students with Complex and Multiple Disabilities, Jerusalem P.O. Box 96342, Israel. <sup>3</sup> Sheba Medical Center, Ramat Gan P.O. Box 52621, Israel. <sup>4</sup> Sackler Faculty of Medicine, Department of Imaging, Tel Aviv University, Tel-Aviv P.O. Box 39040, Israel. <sup>5</sup> Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv P.O. Box 39040, Israel. Conference/Journal: Int J Environ Res Public Health Date published: 2021 Dec 3 Other: Volume ID: 18 , Issue ID: 23 , Pages: 12756 , Special Notes: doi: 10.3390/ijerph182312756. , Word Count: 255 Background: Normal aging is associated with balance and working memory decline. From a neurobiological standpoint, changes in cerebellar functional plasticity may mediate the decline in balance and working memory for older adults. Mounting evidence suggests that physical activity is beneficial for decreasing aging effects. Previous studies have focused on land-based physical activity and research concerning the aquatic environment is scarce. This study investigated the effectiveness of Ai-Chi on balance abilities and cerebral activation during a high working memory load task among community-dwelling older people. Methods: A total of 19 people aged 65-86 years were allocated to receive Ai-Chi practice (n = 6), structured on-land Ai-Chi practice (n = 7) or guided-imagery of Ai-Chi practice (n = 6) for a bi-weekly, 30-min exercise session for 12 weeks. Balance was measured by the Tinetti balance sub-test and working memory was measured by the N-back test during functional-MRI scan. Results: The Ai-Chi practice group presented a significant change in balance between pre and post intervention (balance t = -4.8, p < 0.01). In the whole-brain analysis, during high working memory load task, the Ai-Chi practice group presented a decrease in left cerebellar activation. Region of interest analyses yielded similar results by which pre-cerebellar activation was higher than post-intervention (t = 2.77, p < 0.05). Conclusions: Ai-Chi is an available, non-invasive intervention method that may serve as a tool to improve cerebellar activation that in turn might improve balance. In addition, our findings may provide new insights into the neuronal mechanisms that underlie both motor and cognitive abilities. Keywords: N-back; ageing population; aquatic therapy; balance; cerebellum; f-MRI. PMID: 34886482 PMCID: PMC8656797 DOI: 10.3390/ijerph182312756