Huntington’s disease (HD) is a neurodegenerative familial disease encoded by a CAG expansion mutation in the gene that encodes the protein huntingtin (htt). The abnormal function of mutated htt causes a progressive brain degeneration which in turn causes a sequence of motor, behavioral and cognitive impairment up to dementia. Even though a genetic test allows preclinical diagnosis many years before the clinical onset, there is no effective therapy to stop the disease to date. For that reason, the identification of biomarkers of brain changes, and cognitive/behavioural premorbid profile at presymptomatic stages of the disease may represent an effective strategy to monitor the progression of the pathological process and to assess the potential efficacy of preventive treatments since before the appearance of clinical manifestations.Neuropathological studies have described cerebral changes since the early stages of the disease mainly in the striatum, but also in other subcortical nuclei and cortical areas. MRI measures conversely are sensitive to the cerebral changes occurring since presymptomatic stages of the disease. Due the complexity of the changes affecting cerebral tissue in HD (i.e. loss of neurons, htt inclusions, reactive gliosis and iron accumulation); the use of a multimodal MRI protocol providing correlated measures sensitive to different characteristics of brain tissue is expected to be introduced in the clinical practice to monitor the complexity of the pathology. All things considered, the current application aims at 1) testing multiple imaging and cognitive/behavioural markers in presymptomatic stages of the disease to evaluate their efficacy to detect disease onset and disease-stage; 2) exploring the relationships between cerebral impairment and behavioural disturbances trying to identify clinical phenotypes; 3) evaluating the influence of the CAG repeat length on cerebral impairment