Normal aging is associated with general structural brain atrophy and cognitive decline. However, previous research showed that stimulating the brain through training and learning processes might partially countervail and prevent the age-related grey matter volume decline as well as cognitive decline. Lifelong music practice was demonstrated to be a promising intervention in this sense. Recent data on non-musician elderly suggest that musical training induces behavioral benefits. However, research about structural brain plasticity induced by musical training in non-musician healthy elderly is lacking. The present longitudinal randomized controlled trial study investigated the grey matter volume plasticity using voxel-based morphometry and behavioral changes induced by 6-month musical intervention in 132 healthy retired elderly (62-78 years old). The study was conducted at two sites (Geneva and Hanover). Participants received either piano courses (experimental group, N = 66) or musical culture lessons with active musical listening (active control group, N = 66). Each group received 1-hour courses per week and daily homework. Participants were tested at baseline and after 6 months of interventions via structural neuroimaging and behavioral measurements. Concerning the latter, this Master's thesis focuses only on psychometric tests evaluating manual dexterity and auditory selective attention. After 6 months of training, both groups showed robust increase of grey matter volume in the left caudate nucleus, the left/right cerebellum and the right Rolandic operculum. This brain plasticity was related to an increase in tonal working memory performance over time (progress). Both groups taken separately, the control group showed more widespread plasticity changes than the piano group. However, the piano group showed greater grey matter volume increase/stabilization after the intervention in a set of regions of interest, namely the right hippocampus, and primary sensorimotor and auditory areas. In addition, the piano group showed greater improvement in left ear auditory selective attention compared to the control group. Yet behavioral changes did not relate to hippocampal, sensorimotor and auditory plasticity. Our results suggest that musical practice and active musical listening might therefore be promising approaches to partially countervail age-related brain structural and cognitive decline.