出版社：Centro Interamericano de Investigaciones Psicológicas y Ciencias Afines
摘要：Tradicionalmente la memoria semánticahasido definida como un tesoro mental que alma-cena información sobre las palabras, su signifi-cado, como así también la relación entre ellas,los hechos y los conceptos. Una de las vías prin-cipales para explicar cómo se organiza la infor-mación en la memoria semántica (MS) es atra vés de categorías. La demencia tipo Alzheimer(DTA) suele estar caracterizada por un deterioroen la memoria episódica. Sin embargo, se debateen tor no al deterioro de la misma, en qué mo-mento aparece, a qué se debe y si hay una pér-dida diferencial en distintos momentos de laen fermedad. El objetivo del trabajo que se in-forma fue analizar los procesos de categoriza-ción semántica en adultos mayores sanos com- parándolos con dos grupos de personas con pa-tologías neurológicas: uno con diagnóstico dedeterioro cognitivo leve (DCL) y otro con de-mencia tipo Alzheimer (DTA), emparejados poredad, nivel educativo y género. Para ello, se uti-lizaron tareas tradicionales para evaluar la me-moria semántica y también un método novedoso,el DISTSEM, que permite evaluar las estimacio-nes que realizan las personas de las distanciassemánticas entre los conceptos. Los resultadosmostraron que el grupo de personas sin patologíatuvo un rendimiento superior en todas las tareasen comparación con los grupos de personas conpatología neurológica. Por otro lado, el grupocon DTA mostró un deterioro semántico afec-tando en primer lugar a la categoría seres vivos.El DCL preservó la estructura categorial só locon pequeñas intrusiones. El DISTSEM mostróser un instrumento adecuado para la dis cri- minación entre sujetos sanos y DTA.
其他摘要：Traditionally, semantic memory has been defined as a mental trove that contains organized information about words and their meaning, as well as relationships between words, facts and concepts. There are different ways of explaining how the information in such memory system is represented and organized. One of the main ways of explaining this organization is through categories. Categor - ization starts the very moment that any sensorial perception is associated to an abstract category; it is the ability to organize information in equivalence classes, and it is very important because it allows us to summarize the information that we gather through our senses and thus facilitate its manip - ulation. Alzheimer’s disease (AD) is the main cause of dementia among older adults, and it is one of the most pressing sanitary, social and cultural problems of the present times. The main risk factor for the illness is age, for its prevalence augments exponen - tially from 65 to 85 years old, and due to the rise in life expectancy it is considered that it might be transformed into a world-wide epidemic in the coming years. The start of the illness is insidious and slowly progressing, and it is characterized by a loss of episodic memory from its beginnings. With respect to the deterioration of semantic memory in AD, a debate has arisen about its mode of presentation, its causes, and whether there is a differential loss of categories (live or non-live beings) in different moments of the illness. During the 90s, Petersen proposed the concept of mild cognitive impairment (MCI) to label the subjects with a functional cognitive impairment insufficient to diagnose a dementia syndrome. The importance of this syndrome is that between 8 to 15% of those who suffer it evolve to AD annually, while in the general population this evolution is only from 1 to 2%. However, there is a great controversy about the validity and scope of the term MCI, for its etiology can be very varied and it is very difficult to predict its evolution. There are different sub- kinds of MCI, and the amnesic form is the more likely to evolve into AD, for its main characteristic is the subjective deterioration of memory corr - oborated by standardized test by reference to normative data for the same age and educational level of the subject. The other cognitive functions not present alterations. The main objective of this work was to analyze the semantic categorization processes in healthy older adults comparing them with two groups of people with neurological pathologies, one with diagnosis of MCI and the other with AD, matched by age, educational level and gender. To evaluate this categorization process, two traditional tasks were used together with a novel method, the DISTSEM , which allows the evaluation of the estimation made by people about the semantic distance among a set of given con - cepts. The results showed that the group of people without pathologies had a superior performance in all the tasks in comparison with the groups of people with neurological pathologies. On the other hand, the group with AD showed a semantic impairment which affected in the first place the category of live beings, which was evident in the all the tasks. The MCI preserved the categorical struc - ture with only minor intrusions. The DISTSEM has shown itself to be a valuable instrument that allows the discrimination between healthy subjects and those with AD. It is expected that this work can provide empirical evidence relevant to the debate surrounding semantic memory, for studies in patients with brain injury offer key information to examine the organizing models of such memory.
关键词：Categorización semántica; Adul-tos mayores; DISTSEM; Deterioro cognitivo le -ve (DCL); Demencia tipo Alzheimer (DTA).
