CANTAB object recognition and language tests to detect aging cognitive decline: an exploratory comparative study

Fernanda Cabral Soares,1 Thaís Cristina Galdino de Oliveira,1 Liliane Dias e Dias de Macedo,1 Alessandra Mendonça Tomás,1 Domingos Luiz Wanderley Picanço-Diniz,2 João Bento-Torres,1,3 Natáli Valim Oliver Bento-Torres,1,3 Cristovam Wanderley Picanço-Diniz1 1Universidade Federal do Pará, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Laboratório de Investigações em Neurodegeneração e Infecção Belém, Pará, Brazil; 2Universidade Federal do Oeste do Pará, Núcleo Universitário de Oriximiná, Oriximiná, Pará, Brazil; 3Faculdade de Fisioterapia e Terapia Ocupacional, Universidade Federal do Pará, Belém, Pará, BrazilObjective: The recognition of the limits between normal and pathological aging is essential to start preventive actions. The aim of this paper is to compare the Cambridge Neuropsychological Test Automated Battery (CANTAB) and language tests to distinguish subtle differences in cognitive performances in two different age groups, namely young adults and elderly cognitively normal subjects.Method: We selected 29 young adults (29.9±1.06 years) and 31 older adults (74.1±1.15 years) matched by educational level (years of schooling). All subjects underwent a general assessment and a battery of neuropsychological tests, including the Mini Mental State Examination, visuospatial learning, and memory tasks from CANTAB and language tests. Cluster and discriminant analysis were applied to all neuropsychological test results to distinguish possible subgroups inside each age group.Results: Significant differences in the performance of aged and young adults were detected in both language and visuospatial memory tests. Intragroup cluster and discriminant analysis revealed that CANTAB, as compared to language tests, was able to detect subtle but significant differences between the subjects.Conclusion: Based on these findings, we concluded that, as compared to language tests, large-scale application of automated visuospatial tests to assess learning and memory might increase our ability to discern the limits between normal and pathological aging. Keywords: aging, neuropsychological tests, cluster analysis, discriminant analysi

Age and Environment Influences on Mouse Prion Disease Progression: Behavioral Changes and Morphometry and Stereology of Hippocampal Astrocytes

Because enriched environment (EE) and exercise increase and aging decreases immune response, we hypothesized that environmental enrichment and aging will, respectively, delay and increase prion disease progression. Mice dorsal striatum received bilateral stereotaxic intracerebral injections of normal or ME7 prion infected mouse brain homogenates. After behavior analysis, animals were euthanized and their brains processed for astrocyte GFAP immunolabeling. Our analysis related to the environmental influence are limited to young adult mice, whereas age influence refers to aged mice raised on standard cages. Burrowing activity began to reduce in ME7-SE two weeks before ME7-EE, while no changes were apparent in ME7 aged mice (ME7-A). Object placement recognition was impaired in ME7-SE, NBH-A, and ME7-A but normal in all other groups. Object identity recognition was impaired in ME7-A. Cluster analysis revealed two morphological families of astrocytes in NBH-SE animals, three in NBH-A and ME7-A, and four in NBH-EE, ME7-SE, and ME7-EE. As compared with control groups, astrocytes from DG and CA3 prion-diseased animals show significant numerical and morphological differences and environmental enrichment did not reverse these changes but induced different morphological changes in GFAP+ hippocampal astroglia. We suggest that environmental enrichment and aging delayed hippocampal-dependent behavioral and neuropathological signs of disease progression

Beneficial effects of multisensory and cognitive stimulation in institutionalized elderly: 12-months follow-up

Liliane Dias E Dias de Macedo,1 Thaís Cristina Galdino De Oliveira,1 Fernanda Cabral Soares,1 João Bento-Torres,1,2 Natáli Valim Oliver Bento-Torres,1,2 Daniel Clive Anthony,3 Cristovam Wanderley Picanço-Diniz1 1Laboratory of Investigations in Neurodegeneration and Infection, Institute of Biological Sciences, University Hospital João de Barros Barreto, Federal University of Pará, 2College of Physical Therapy and Occupational Therapy, Federal University of Para, Belem, Para, Brazil; 3Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford, England, UKAbstract: We previously demonstrated the beneficial effects of a multisensory and cognitive stimulation program, consisting of 48 sessions, twice a week, to improve the cognition of elderly subjects living either in long-term care institutions (institutionalized – I) or in communities with their families (noninstitutionalized – NI). In the present study, we evaluated these subjects after the end of the intervention and compared the rate of age-related cognitive decline of those living in an enriched community environment (NI group, n=15, 74.1±3.9 years old) with those living in the impoverished environment of long-term care institutions (I group, n=20, 75.1±6.8 years old). Both groups participated fully in our stimulation program. Over 1 year, we conducted revaluations at five time points (2 months, 4 months, 6 months, 8 months, and 12 months) after the completion of the intervention. Both elderly groups were evaluated with the mini-mental state examination and selected language tests. Progressive cognitive decline was observed in both groups over the period. Indeed, it took only 4–6 months after the end of the stimulation program for significant reductions in language test scores to become apparent. However, earlier reductions in test scores were mainly associated with I group, and linguistic prosody test scores were significantly affected by institutionalization and time, two variables that interacted and reduced these scores. Moreover, I group reduced the Montréal cognitive assessment battery language tests scores 4 months before NI group. It remains to be investigated what mechanisms may explain the earlier and more intense language losses in institutionalized elderly. Keywords: age-related cognitive impairment, multisensory and cognitive stimulation, long-term care institutions, community living, language assessmen

Density, proportion, and dendritic coverage of retinal ganglion cells of the common marmoset (Callithrix jacchus jacchus)

We performed a quantitative analysis of M and P cell mosaics of the common-marmoset retina. Ganglion cells were labeled retrogradely from optic nerve deposits of Biocytin. The labeling was visualized using horseradish peroxidase (HRP) histochemistry and 3-3'diaminobenzidine as chromogen. M and P cells were morphologically similar to those found in Old- and New-World primates. Measurements were performed on well-stained cells from 4 retinas of different animals. We analyzed separate mosaics for inner and outer M and P cells at increasing distances from the fovea (2.5-9 mm of eccentricity) to estimate cell density, proportion, and dendritic coverage. M cell density decreased towards the retinal periphery in all quadrants. M cell density was higher in the nasal quadrant than in other retinal regions at similar eccentricities, reaching about 740 cells/mm² at 2.5 mm of temporal eccentricity, and representing 8-14% of all ganglion cells. P cell density increased from peripheral to more central regions, reaching about 5540 cells/mm² at 2.5 mm of temporal eccentricity. P cells represented a smaller proportion of all ganglion cells in the nasal quadrant than in other quadrants, and their numbers increased towards central retinal regions. The M cell coverage factor ranged from 5 to 12 and the P cell coverage factor ranged from 1 to 3 in the nasal quadrant and from 5 to 12 in the other quadrants. These results show that central and peripheral retinal regions differ in terms of cell class proportions and dendritic coverage, and their properties do not result from simply scaling down cell density. Therefore, differences in functional properties between central and peripheral vision should take these distinct regional retinal characteristics into account