Inclusion Criteria:  - Mild Cognitive Impairment due to Alzheimer's disease (according to Albert et al., Alzheimers Dement 2011).  Exclusion Criteria:  Cerebrovascular disorders, previous stroke, hydrocephalus, and intra-cranial mass documented by MRI. History of traumatic brain injury or other neurological diseases. Serious medical illness other than FTD History of seizures Pregnancy Metal implants in the head (except dental fillings) Electronic implants (i.e. pace-maker, implanted medical pump) Age <18 years