The dynamics of the resting brain exhibit transitions between a small number of discrete networks, each remaining stable for tens to hundreds of milliseconds. These functional microstates are thought to be the building blocks of spontaneous consciousness. The electroencephalogram (EEG) is a useful tool for imaging microstates, and EEG microstate analysis can potentially give insight into altered brain dynamics underpinning cognitive impairment in disorders such as Alzheimer’s disease (AD). Since EEG is non-invasive and relatively inexpensive, EEG microstates have the potential to be useful clinical tools for aiding early diagnosis of AD. In this study, EEG was collected from two independent cohorts of probable AD and cognitively healthy control participants, and a cohort of mild cognitive impairment (MCI) patients with four-year clinical follow-up. The microstate associated with the frontoparietal working-memory/attention network was altered in AD due to parietal inactivation. Using a novel measure of complexity, we found microstate transitioning was slower and less complex in AD. When combined with a spectral EEG measure, microstate complexity could classify AD with sensitivity and specificity > 80%, which was tested on an independent cohort, and could predict progression from MCI to AD in a small preliminary test cohort of 11 participants. EEG microstates therefore have potential to be a non-invasive functional biomarker of AD.

Studies on the distribution of multiple sclerosis (MS) carried out in Southern Europe in the last years have shown a significant increase in the frequency of the disease. A previous descriptive survey in the Republic of San Marino, northern Italian peninsula, published in 1984 established that this area is at high risk for MS. We updated the frequency estimates of the disease by adopting a complete enumeration approach. On 31 December 2005, 50 MS patients (36 women and 14 men) yielded a crude prevalence rate of 166.7 per 100, 000 (95% CI 123.7-220), 235.3 (95% CI 165-327.4) for women and 95.2 (95% CI 52-160) for men. The average incidence from 1990 to 2005 was 7.9 (95% CI 5.3-11.1) per 100,000, 11.7 (95% CI 7.6-17.3) for women and 3.9 (95% CI 1.7-7.7) for men. We did not detect any significant temporal trend over the study period. These results confirm that in San Marino the disease occurs more frequently than that suggested in the past and support the data on MS frequency in continental Italy. The marked increase in MS prevalence ratio is partly due to the increasing survival of patients and the accumulation of new incidence cases owing to the reduction in diagnostic latency for better quality of neurological diagnostic procedures. However, an increased incidence of the disease could be considered.

Our findings suggested that the TIMP-1 resistant MMP-9 seem to be the predominantly active isoform contributing to MS disease activity.

Several case-control and cohort studies have suggested an association between migraine and stroke. A significantly higher risk for stroke was found in women under the age of 45 years and for the subgroup with migraine with aura, the posterior circulation being significantly more frequently involved. The link between cardiac diseases and the comorbidity migraine-stroke has been evaluated considering both possible relationships: a higher prevalence of a vascular disease involving both heart and brain in migraineurs, or a cardiac disorder, more prevalent in migraineurs, with a possible aetiological role in migraine attacks.