Is Losing One's Way a Sign of Cognitive Decay? Topographical Memory Deficit as an Early Marker of Pathological Aging.

Spatial navigation tasks reveal small differences between normal and pathological aging and may thus disclose potential neuropsychological predictors of neurodegenerative diseases. The aim of our study was to investigate which navigational skills are compromised in the early phase of pathological aging as well as the extent to which they are compromised. We performed an extensive neuropsychological evaluation based on working memory and learning tasks (i.e., Corsi Block-Tapping Test and Walking Corsi Test) involving both reaching and navigational vista spaces. We also assessed spatial navigation skills in the real world by asking participants to perform route-learning and landmark-recognition tasks. We conducted a cross-sectional study on nineteen patients with a diagnosis of mild cognitive impairment (MCI) who displayed either an isolated memory deficit (single-domain amnestic MCI, MCIsd; N = 3) or a memory deficit associated with deficits in other cognitive functions (multi-domain MCI, MCImd; N = 16) as well as on nineteen healthy control participants. The groups' performances were compared by means of mixed factorial ANOVA and two-sample t-tests. We found that patients with MCI performed worse than controls, especially when they were required to learn spatial positions within the navigational vista space. Route-learning within the real environment was also impaired whereas landmark-recognition was spared. The same pattern of results emerged in the MCImd subgroup. Moreover, single case analyses on MCIsd patients revealed a dissociation between learning of spatial positions within navigational vista space and within reaching space. These results suggest that topographical learning is compromised in the early phase of MCIsd and MCImd and that spatial navigation tasks may be used to better characterize topographical disorientation in MCI patients as well as for the early diagnosis of pathological aging.

Cognitive Training in Patients with Alzheimer's Disease: Findings of a 12-month Randomized Controlled Trial.

BACKGROUND: Cognitive training (CT) is a non-pharmacological intervention based on a set of tasks that reflect specific cognitive functions. CT is aimed at improving cognition in patients with cognitive impairment, though no definitive conclusions have yet been drawn on its efficacy in Alzheimer's disease (AD). OBJECTIVE: To assess the effectiveness of a CT program designed to improve cognition in AD patients. METHOD: This is a randomized, controlled, single-blind, longitudinal trial with a no-treatment control condition in mild-to-moderate AD. Treated patients received in-group CT twice a week for six months, whereas controls did not. CT consisted of tasks ranging from paper-and-pencil to verbal-learning exercises. Participants' cognitive levels were assessed at baseline, post-intervention and 6 months later by means of a complete neuropsychological test battery. Repeated measures ANOVA was used to analyze the effect of time on the outcome measures, as well as to compare treated and untreated patients over time, with demographic data considered as covariates. RESULTS: Of the 140 patients enrolled, 45 in the treated group and 85 controls concluded the study. The CT significantly improved treated subjects' cognitive functions immediately after the CT. Six months later, some test scores remained stable when compared with those obtained at baseline. The control group performed significantly worse than the treated group at each time-point, displaying a progressive cognitive decline over time. CONCLUSION: Our results suggest that CT may improve cognitive functions in patients with AD and may help to temporarily slow their cognitive decline.

The Impact of Frailty on the Risk of Conversion from Mild Cognitive Impairment to Alzheimer's Disease: Evidences from a 5-Year Observational Study.

The frailty construct has increasingly been adopted in the field of cognitive disorders. The aim of the present study was to measure frailty in a cohort of individuals with mild cognitive impairment (MCI) and to explore whether frailty measures may consent to predict the risk of conversion to dementia. We retrospectively reviewed the clinical charts of outpatients with amnesic MCI (aMCI) consecutively recruited at our Department, and followed-up for 5 years. Individual frailty status was measured by means of a frailty index (FI) consisting of 39 deficits (including signs, symptoms, diagnoses, and disabilities). Univariate analyses were used to compare the socio-demographic and clinical characteristics between subjects converting or not converting to probable Alzheimer's disease (AD) dementia over the follow-up. Risk for conversion to AD dementia was assessed using Cox regression models. Ninety-one subjects with aMCI (mean age 72.7, SD 7.1 years; women 49.5%) were consecutively recruited over a period of 12 months. Low levels of frailty were documented in the sample (mean FI score 10.0, SD 5.3). A statistically significant correlation between age and FI was observed. Overall, 58 participants converted to AD dementia over time. The Cox regression analysis showed that age (HR: 1.04, 95% CI: 1.00-1.08), male sex (HR: 0.52, 95% CI: 0.30-0.91), Mini-Mental State Examination score (HR: 0.85, 95% CI: 0.77-0.94), and FI (HR: 1.11, 95% CI: 1.05-1.18) were all significantly associated with the probability of MCI conversion. Individual's frailty status may increase the risk of conversion from a condition of MCI to overt AD dementia. The adoption of constructs comprehensively reflecting the biological decline of the aging subject may add useful estimates and information in the clinical approach to cognitive disorders.

Musical cognition in Alzheimer's disease: application of the Montreal Battery of Evaluation of Amusia.

The aim of this study was to assess certain musical abilities in 30 patients with Alzheimer's disease (AD) and 30 healthy controls by using the complete version of the Montreal Battery of Evaluation of Amusia (MBEA). This battery evaluates melodic (scale, contour, and interval) and temporal (rhythm and meter) perception of music and musical memory. We found that altered musical processing is a common feature in AD. Despite that, AD subjects show partially spared abilities for temporal organization of music, though not for melodic perception and musical memory. This peculiar dysfunctional pattern could depend on the neurodegenerative involvement of some specific areas for music perception and memory in the brains of AD patients. Further studies are needed to investigate the usefulness of additional musical tests like the MBEA on larger samples to confirm our preliminary data.