Research Article Correlation between Motor Cortex Excitability Changes and Cognitive Impairment in Vascular Depression: Pathophysiological Insights from a Longitudinal TMS Study Manuela Pennisi, 1 Giuseppe Lanza, 2 Mariagiovanna Cantone, 2 Riccardo Ricceri, 3 Concetto Spampinato, 4 Giovanni Pennisi, 5 Vincenzo Di Lazzaro, 6 and Rita Bella 3 1 Spinal Unit, Emergency Hospital “Cannizzaro”, 95126 Catania, Italy 2 Department of Neurology I.C., “Oasi” Institute for Research on Mental Retardation and Brain Aging (I.R.C.C.S.), 94018 Troina, Italy 3 Department of Medical and Surgical Sciences and Advanced Technologies, Section of Neurosciences, University of Catania, 95125 Catania, Italy 4 Department of Electrical, Electronics and Informatics Engineering, University of Catania, 95125 Catania, Italy 5 Department of Surgery and Medical-Surgical Specialties, University of Catania, 95125 Catania, Italy 6 Department of Medicine, Unit of Neurology, Neurophysiology, Neurobiology, Campus Bio-Medico University of Rome, 00128 Rome, Italy Correspondence should be addressed to Rita Bella; rbella@unict.it Received 26 January 2016; Revised 14 March 2016; Accepted 30 May 2016 Academic Editor: Zygmun Galdzicki Copyright © 2016 Manuela Pennisi et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Transcranial magnetic stimulation (TMS) highlighted functional changes in dementia, whereas there are few data in patients with vascular cognitive impairment-no dementia (VCI-ND). Similarly, little is known about the neurophysiological impact of vascular depression (VD) on deterioration of cognitive functions. We test whether depression might afect not only cognition but also specifc cortical circuits in subcortical vascular disease. Methods. Sixteen VCI-ND and 11 VD patients, age-matched with 15 controls, underwent a clinical-cognitive, neuroimaging, and TMS assessment. Afer approximately two years, all participants were prospectively reevaluated. Results. At baseline, a signifcant more pronounced intracortical facilitation (ICF) was found in VCI- ND patients. Reevaluation revealed an increase of the global excitability in both VCI-ND and VD subjects. At follow-up, the ICF of VCI-ND becomes similar to the other groups. Only VD patients showed cognitive deterioration. Conclusions. Unlike VD, the hyperfacilitation found at baseline in VCI-ND patients suggests enhanced glutamatergic neurotransmission that might contribute to the preservation of cognitive functioning. Te hyperexcitability observed at follow-up in both groups of patients also indicates functional changes in glutamatergic neurotransmission. Te mechanisms enhancing the risk of dementia in VD might be related either to subcortical vascular lesions or to the lack of compensatory functional cortical changes. 1. Introduction Among the factors that contribute to cognitive decline in older adults, there is now agreement that depression of the late life is one of the recognized clinical risk factors for dementia [1–3]. In a recent clinical-pathological study, the presence of depression prior to the onset of dementia was found to be more common and more drug-resistant in patients with vascular dementia (VaD) than in those with Alzheimer’s disease (AD) [4]. A close relationship between depression, cognitive impairment, and cerebrovas- cular pathology has been also reported in vascular depression (VD), based on the evidence that white matter lesions (WMLs) are more common and more severe in individuals with late-onset depression than in healthy subjects or in patients with early-onset depression [5]. In particular, it has been hypothesized that the efects of the ischemic dam- age of the frontal cortical-subcortical circuits implicated in Hindawi Publishing Corporation Neural Plasticity Volume 2016, Article ID 8154969, 10 pages http://dx.doi.org/10.1155/2016/8154969