Blood sample and MRI measures were collected on different days before the memory task. MRI and genetic analyses were performed at during the secondment periods. The entire research was hosted and supervised by Casa di Cura del Policlinco (CCP, Milan, Italy). During the memory task, older adults with aMCI (n=15) learned 20 words. 24h later, participants received PFC-tDCS (active or sham). Memory recognition was tested 48h and one month after the learning session. The behavioural results did not show a positive effect of active tDCS on memory recognition performance relative to sham tDCS. The genetic analyses showed that most of the aMCI patients were carriers of specific polymorphisms that have been associated to pathological conditions characterized by episodic memory decline. Regarding the correlations between memory performance and gray/white matter measures, there was a statistically significant correlation between memory recognition performance at Day 3 and white matter microstructure of the left Uncinate Fasciculus (UF), a large white matter bundle linking functionally regions of the temporal lobe to regions of the frontal lobe.
Although a larger sample size is needed in order to make reliable conclusions, the lack of a behavioural effect might be due to the fact that MCI is a heterogeneous population. In addition, patients with aMCI were diagnosed on the basis of clinical criteria without assessing the accumulation of amyloid plaques in the brain, one of the hallmarks of AD. Therefore, it was not possible to determine if the patients enrolled were MCI due to AD.
To achieve his training objectives the fellow performed neuropsychological assessments, observed clinical activities and cognitive interventions in patients with neurological disorders. He attended clinical rounds, journal clubs and seminars about neurological cases, novel interventions and their mechanism of action. He acquired skills in MRI analysis to map the structural changes associated with neurological disorders in order to better understand the pathological processes and to monitor the effects of treatment interventions on brain structure. He also observed the basic procedures to perform analysis of specific genetic polymorphisms. Finally, he gave lectures at high schools and universities using a research-based teaching approach. He presented his research on human memory and the MemoMCI project at different universities and research institutions in Italy (n=2: Padova, Milan), UK (n=4, London) and US (n=1). He also participated as a speaker in workshops and conferences regarding neurorehabilitation (n=5). Furthermore, he presented preliminary data of the MemoMCI project at an event about memory and dementia organized by the host institution exclusively dedicated to general practitioners. In collaboration with the Scientific Director, Dr. Massimo Corbo, the fellow wrote an opinion article about the possibility to modulate reconsolidation with non-invasive brain stimulation, and organized a workshop at CCP about the use of tDCS as an adjuvant strategy for rehabilitation of motor and cognitive deficits. From this workshop emerged that further investigations on extensive case studies, through neuroimaging and neurophysiological techniques, are indispensable to better clarify the complex mechanisms of basic action and determine the duration of the tDCS-induced effects.
