Predicting Working Memory Capacity in Older Subjects Using Quantitative Electroencephalography

OBJECTIVE: We utilized a spectral and network analysis technique with an integrated support vector classification algorithm for the automated detection of cognitive capacity using resting state electroencephalogram (EEG) signals. METHODS: An eyes-closed resting EEG was recorded in 158 older subjects, and spectral EEG parameters in seven frequency bands, as well as functional brain network parameters were, calculated. In the feature extraction stage, the statistical power of the spectral and network parameters was calculated for the low-, moderate-, and high-performance groups. Afterward, the highly-powered features were selected as input into a support vector machine classifier with two discrete outputs: low- or high-performance groups. The classifier was then trained using a training set and the performance of the classification process was evaluated using a test set. RESULTS: The performance of the Support Vector Machine was evaluated using a 5-fold cross-validation and area under the curve values of 70.15% and 74.06% were achieved for the letter numbering task and the spatial span task. CONCLUSION: In this study, reliable results for classification accuracy and specificity were achieved. These findings provide an example of a novel method for parameter analysis, feature extraction, training, and testing the cognitive function of elderly subjects based on a quantitative EEG signal.

Brain regions supporting verbal memory improvement in healthy older subjects / Regiões do cérebro relacionadas à melhora da memória verbal em idosos saudáveis

Despite growing interest in developing cognitive training interventions to minimize the aging cognitive decline process, no studies have attempted to explore which brain regions support the application of semantic strategies during verbal memory encoding. Our aim was to investigate the behavioral performance and brain correlates of these strategies in elderly individuals using fMRI in healthy older subjects. Method Subjects were scanned twice on the same day, before and after, directed instructions to apply semantic strategies during the encoding of word lists. Results Improved memory performance associated to increased semantic strategy application and brain activity in the left inferior and middle and right medial superior prefrontal cortex were found after the directed instructions. There was also reduced activation in areas related to strategy mobilization. Conclusion Improved memory performance in older subjects after the application of semantic strategies was associated with functional brain reorganization involving regions inside and outside the typical memory network. .

Apesar do crescente interesse em intervenções de treinamento cognitivo para minimizar o declínio cognitivo do envelhecimento, nenhum estudo explorou quais regiões do cérebro estão relacionadas à aplicação de estratégias semânticas durante a codificação da memória verbal. Nosso objetivo foi investigar o comportamento e correlatos cerebrais associados a essas estratégias usando fMRI em idosos saudáveis. Método Os sujeitos foram examinados no mesmo dia, antes e depois, de instruções dirigidas para aplicar estratégias semânticas durante a codificação de palavras. Resultados Melhora da memória relacionada ao uso de estratégias semânticas e aumento da atividade no córtex prefrontal inferior e medial esquerdo e medial superior direito foram encontrados após as instruções. Também houve redução de ativação em áreas de mobilização de estratégias. Conclusão A melhora da memória em idosos após o uso de estratégias semânticas estava associada à reorganização cerebral funcional envolvendo regiões dentro e fora da rede de áreas cerebrais típicas da memória. .

Estudio clínico epidemiológico de xerostomia en adultos mayores desdentados totales / Clinical epidemiological study of xerostoma in eldery totally edentulous

Introducción y objetivo: Debido al aumento de la población anciana en nuestra sociedad, aquejada por disminución variable del flujo salival, influyendo en su calidad de vida, el objetivo de este trabajo fue analizar la prevalencia de la disminución salival y xerostomÍa en relación con distintos factores causales.Materiales y métodos: A 126 individuos edén tul os , mayores de 50 años de edad (x 62,41 ::1:::8,24), de ambos sexos, se realizó una historia clínica diseñada al efecto, registrando los factores locales y generales predisponentes. Los resultados se analizaron estadísticamente (p< 0,05). Resultados: 40,5% presentó xerostomía, con mayor cantidad de casos a mayor edad y sexo femenino, con diferencias significativas en mujeres de 60 a 69 años de edad. El 34,9% estaba aparentemente sano y e165,1 % padecía una o más enfermedades sistémicas y el 53,3% usaba cotidianamente medicación (x 2,14::1::: 1,10 drogas diarias).Discusión: Escaso flujo salival y sensación de sequedad oral se relacionaron con problemas médicos y uso de medicamentos, con diferencias significativas. El estudio mostró al aumento de la edad y el sexo femenino como factores en la disminución del flujo salival y xerostomía, pudiendo ser afectado por la edad, los enfermedades y/ o la medicación, que se acentúan con la edad. Conclusiones: La xerostomía no es una enfermedad sino una manifestación clínica de sensación de sequedad oral con o sin hiposialia. De etiología diversa, al ser identificada permite un plan de tratamiento que deberán proyectar juntos distintos profesionales de la salud.

Introduction: Because of an increasing number of older people in our community presenting with a variable decrease of salivary flow which affects their quality of life, we aimed to analyze the prevalence of salivary decrease and xerostomia in relation to various causing factors. Purpose.-The objective of this study was to analyze the prevalence of a decrease of normal salivary secretion and xerostomia in relation to various factors in the older population of our community. Material and method.- One hundred and twenty-six edentulous male and female subjects older than 50 years (62.41 8,24) were entered . A chart was specially designed for this study where both local and general predisposing factors were...