David Facal

Prevalence and Correlates of Cognitive Impairment in Adults with Subjective Memory Complaints in Primary Care Centres

Aims: To examine the prevalence and correlates of cognitive impairment (CI) in adults over 50 years old attending primary care centres with complaints of memory failure. Methods: A sample of 580 individuals aged 50+ years with no previous diagnosis of dementia was assessed by use of the Mini Mental State Examination, the Cambridge Cognitive Assessment-Revised and the California Verbal Learning Test – to evaluate CI-dependent variables – and administration of a questionnaire on memory complaints and other instruments – to measure correlates. Results: The prevalence of CI was 46.20% and positive associations were found for age, gender, level of education, subjective memory complaints, instrumental activities of daily living, reading habits and frequency of leisure activities. In the logistic regression, modelled CI was associated with older age, gender (49.12% women, 39.66% men), instrumental activities of daily living, and reading habits. Conclusion: Almost half of the adults aged 50+ years attending primary care centres with subjective memory complaints were affected by CI. Early evaluation of cognitive functioning is essential to establish adequate preventive and intervention strategies.

User-centered design of a dynamic-autonomy remote interaction concept for manipulation-capable robots to assist elderly people in the home

In this article, we describe the development of a human-robot interaction concept for service robots to assist elderly people in the home with physical tasks. Our approach is based on the insight that robots are not yet able to handle all tasks autonomously with sufficient reliability in the complex and heterogeneous environments of private homes. We therefore employ remote human operators to assist on tasks a robot cannot handle completely autonomously. Our development methodology was user-centric and iterative, with six user studies carried out at various stages involving a total of 241 participants. The concept is under implementation on the Care-O-bot 3 robotic platform. The main contributions of this article are (1) the results of a survey in form of a ranking of the demands of elderly people and informal caregivers for a range of 25 robot services, (2) the results of an ethnography investigating the suitability of emergency teleassistance and telemedical centers for incorporating robotic teleassistance, and (3) a user-validated human-robot interaction concept with three user roles and corresponding three user interfaces designed as a solution to the problem of engineering reliable service robots for home environments.

Towards robust personal assistant robots: Experience gained in the SRS project

SRS is a European research project for building robust personal assistant robots using ROS (Robotic Operating System) and Care-O-bot (COB) 3 as the initial demonstration platform. In this paper, experience gained while building the SRS system is presented. A main contribution of the paper is the SRS autonomous control framework. The framework is divided into two parts. First, it has an automatic task planner, which initialises actions on the symbolic level. The planner produces proactive robotic behaviours based on updated semantic knowledge. Second, it has an action executive for coordination actions at the level of sensing and actuation. The executive produces reactive behaviours in well-defined domains. The two parts are integrated by fuzzy logic based symbolic grounding. As a whole, they represent the framework for autonomous control. Based on the framework, several new components and user interfaces are integrated on top of COBs existing capabilities to enable robust fetch and carry in unstructured environments. The implementation strategy and results are discussed at the end of the paper.

Lexical knowledge and lexical retrieval in ageing: Insights from a tip-of-the-tongue (TOT) study

Elderly people experience more failures in word form access (tip-of-the-tongue events, ‘TOTs’) than young people. There is general agreement that TOTs are signs of cognitive decline in older people, but because of the diversity and ambiguity involved in measuring TOTs, certain questions regarding age-related trends in semantic access remain unsolved. Age-related increases in vocabulary may raise the level of efficiency of access to semantic representations and compensate for lexical access failures. We explore the relationships between lexical knowledge and lexical retrieval in ageing by re-examining the data obtained by Juncos-Rabadán et al. on TOTs induced in 140 volunteers aged from 19 to 82 years. We found that older adults displayed significantly more difficulty in accessing the phonological representations of personal names, but not those of common nouns. The results revealed greater semantic access efficiency in older participants. We discuss the findings in light of the transmission deficit theory of TOT production.

Does tip-of-the-tongue for proper names discriminate amnestic mild cognitive impairment?

BACKGROUND Difficulty in retrieving peoples names is very common in the early stages of Alzheimers disease and mild cognitive impairment. Such difficulty is often observed as the tip-of-the-tongue (TOT) phenomenon. The main aim of this study was to explore whether a famous peoples naming task that elicited the TOT state can be used to discriminate between amnestic mild cognitive impairment (aMCI) patients and normal controls. METHODS Eighty-four patients with aMCI and 106 normal controls aged over 50 years performed a task involving naming 50 famous people shown in pictures. Univariate and multivariate regression analyses were used to study the relationships between aMCI and semantic and phonological measures in the TOT paradigm. RESULTS Univariate regression analyses revealed that all TOT measures significantly predicted aMCI. Multivariate analysis of all these measures correctly classified 70% of controls (specificity) and 71.6% of aMCI patients (sensitivity), with an AUC (area under curve ROC) value of 0.74, but only the phonological measure remained significant. This classification value was similar to that obtained with the Semantic verbal fluency test. CONCLUSIONS TOTs for proper names may effectively discriminate aMCI patients from normal controls through measures that represent one of the naming processes affected, that is, phonological access.

¿Previene la actividad intelectual el deterioro cognitivo? Relaciones entre reserva cognitiva y deterioro cognitivo ligero

An in-depth review is presented of the role that cognitive reserve plays in the emergence of (mild cognitive impairment (MCI), and its progression to dementia by using different indicators. The studies reviewed provide support to the hypothesis that the reserve influences the manifestation of symptoms of cognitive impairment and at least partially, in its progression to dementia. The role of indicators of reserve are discussed, such as educational level, work complexity and cognitive activity in these processes. A model is also presented that argues that people with MCI and low reserves show a steeper decline early in the process of deterioration, compared to the high level of reserve this marked deterioration would have at the end of the process, due to the protective role of this reserve. This raises the need for more empirical research to help consolidate this theoretical model.

Structural model for estimating the influence of cognitive reserve on cognitive performance in adults with subjective memory complaints.

Cognitive reserve (CR) is often operationally defined as a complex structure of latent variables. Here, we present a structural model that analyzes the effect of CR on three cognitive domains: episodic memory, working memory, and general cognitive performance. We developed and analyzed a structural equation model (SEM) to study CR and cognitive performance in 326 participants over 50 years old with subjective memory complaints. The CR construct was found to consist of two factors: (a) educational level and (b) lifestyle. The model revealed that CR had significant direct effects on episodic memory, working memory, and general cognitive performance, and indirect effects on episodic memory via working memory. As a latent construct, CR is related to cognitive performance in participants over 50 years with subjective memory complaints, and it should therefore be considered in the evaluation and diagnosis of such people.

Prevalence and correlates of mild cognitive impairment in adults aged over 50 years with subjective cognitive complaints in primary care centers.

To examine the prevalence and correlates of mild cognitive impairment in adults aged over 50 years attending primary care centers with complaints of cognitive failure.

Una revisión de la investigación sobre lenguaje en el deterioro cognitivo leve

Resumen Aunque existen muchas investigaciones sobre el perfil neuropsicologico del deterioro cognitivo leve (DCL), los estudios centrados en analizar especificamente sus caracteristicas psicolinguisticas no son concluyentes. El objetivo de este estudio es revisar las evidencias disponibles sobre la caracterizacion linguistica del DCL e identificar los mejores candidatos a predecir el DCL. Los estudios poblacionales han encontrado que medidas de fluidez verbal, denominacion y memoria de palabras son buenas predictoras de la evolucion del DCL hacia la demencia. Los estudios experimentales que comparan DCL con otros grupos proponen las tareas de fluidez verbal y de denominacion, y en menor medida otras dimensiones, como la comprension de oraciones y de textos, o la produccion narrativa en cuanto a contenido semantico y estructuracion sintactica. Se informa de los hallazgos de algunos estudios que han buscado los correlatos neurologicos de los procesos implicados en el deterioro del lenguaje en el DCL. La presente revision subraya la necesidad de estudiar nuevas dimensiones linguisticas, sus relaciones con otros procesos cognitivos y sus fundamentos psicofisiologicos. Se menciona tambien la necesidad de realizar experiencias de intervencion que permitan disminuir el deterioro y evitar en la medida de lo posible su evolucion a la demencia.

El fenómeno de la punta de la lengua en el deterioro cognitivo leve. Un estudio piloto

Resumen El presente estudio investiga la denominacion de personas famosas en un grupo de pacientes con deterioro cognitivo leve (DCL) (6 individuos) y un grupo control de personas sanas (13 individuos) equiparados en edad y nivel educativo. Tiene como objetivo estudiar las dificultades en el acceso semantico y fonologico a los nombres propios en pacientes con DCL. Se utilizo una tarea de denominacion a partir de 60 fotos de personas famosas con un paradigma que facilita la produccion de eventos del fenomeno de la punta de la lengua (PDL). Los resultados indicaron que los participantes con DCL producian mas respuestas de PDL positivos, cometian mas errores y resolvian menos PDL que los participantes control sanos. La informacion semantica sobre los personajes era mas difusa en los participantes con DCL que en los controles sanos. Se sugiere que el DCL afecta negativamente a la activacion de las representaciones semanticas y debilita la transmision desde las representaciones semanticas a las representaciones fonologicas.