RESUMEN

INTRODUCTION: Semantic verbal fluency (SVF) is the most commonly used test in the evaluation of normal and pathological functioning, whether it be clinically or experimentally. Several studies have suggested that the age, schooling and culture of the subject all affect performance in this test. To date no research has been conducted that proves whether there are differences between subjects who speak the same language but who come from different countries. PATIENTS AND METHODS: Data from the 'animals' category of the SVF in adult Spanish-speaking subjects and also the influence exerted by culture, age and schooling on the outcomes in this test were both submitted to analysis. The aforementioned variables were compared with the data reported by five research groups. RESULTS: The SVF test yields similar data from one Spanish-speaking country to another, provided that the subjects' age and schooling are taken into account. The differences found in this study may be due to variations in the way the tests are administered and scored rather than any cultural effect. We propose a standardised method of applying the test, so as to allow these variables to be unified in the future. CONCLUSION: Age and schooling are factors that determine performance in the SVF, although this is not true of culture.

Asunto(s)

Pruebas del Lenguaje/normas , Lenguaje , Semántica , Conducta Verbal/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Animales , Comparación Transcultural , Escolaridad , Humanos , México , Persona de Mediana Edad , América del Sur , España

RESUMEN

INTRODUCTION AND AIMS: In this work we review some of the options available in rehabilitation technology that are used to aid people with severe neuromuscular disorders, and which take electrophysiological activity as a source of biological signals with which to design interfaces. DEVELOPMENT: A number of different researchers have generated a novel communication and control system that utilises the electrical activity of the brain as a signal that represents the messages or commands an individual sends to the outside world, without using the normal output pathways of the brain, such as peripheral nerves and muscles; instead, this is achieved through an artificial system that extracts, encodes and applies them, called a brain-computer interface (BCI). The electrophysiological activity for a BCI can be obtained by means of superficial or implanted electrodes, and may therefore be classified as invasive or non-invasive. Five types of brain signals have been explored for use with a BCI: visual evoked potentials, slow cortical potentials, cortical neuronal activity, beta and mu rhythms, and event-related potentials. CONCLUSIONS: Thanks to recent improvements and developments in prototypes, this technology is sure to open up new possibilities of communication and control for the affected population; it also represents a valuable field of multidisciplinary research with numerous interesting applications in areas beyond the sphere of health care.

Asunto(s)

Encéfalo/fisiología , Equipos de Comunicación para Personas con Discapacidad , Enfermedades Neuromusculares/rehabilitación , Dispositivos de Autoayuda , Interfaz Usuario-Computador , Electroencefalografía , Electrofisiología , Humanos

RESUMEN

We analyzed the influence of education and of culture on the neuropsychological profile of an indigenous and a nonindigenous population. The sample included 27 individuals divided into four groups: (a) seven illiterate Maya indigenous participants, (b) six illiterate Pame indigenous participants, (c) seven nonindigenous participants with no education, and (d) seven Maya indigenous participants with 1 to 4 years of education . A brief neuropsychological test battery developed and standardized in Mexico was individually administered. Results demonstrated differential effects for both variables. Both groups of indigenous participants (Maya and Pame) obtained higher scores in visuospatial tasks, and the level of education had significant effects on working and verbal memory. Our data suggested that culture dictates what it is important for survival and that education could be considered as a type of subculture that facilitates the development of certain skills.

Asunto(s)

Cultura , Educación , Pruebas Neuropsicológicas , Adulto , Anciano , Cognición/fisiología , Escolaridad , Femenino , Humanos , Indígenas Norteamericanos , Lenguaje , Masculino , México , Persona de Mediana Edad

RESUMEN

Departing from the observation that illiterates significantly underscore in some neuropsychological tests, a learning-to-read method named NEUROALFA was developed. NEUROALFA is directed to reinforce these underscored abilities during the learning-to-read process. It was administered to a sample of 21 adult illiterates in Colima (Mexico). Results were compared with 2 control groups using more traditional procedures in learning to read. The NEUROPSI neuropsychological test battery was administered to all the participants before and after completing the learning-to-read training program. All 3 groups presented some improvement in the test scores. Gains, however, were significantly higher in the experimental group in Orientation in Time, Digits Backward, Visual Detection, Verbal Memory, Copy of a Semi-Complex Figure, Language Comprehension, Phonological Verbal Fluency, Similarities, Calculation Abilities, Sequences, and all the recall subtests, excluding Recognition. Performance in standard reading tests was also significantly higher in the experimental group. Correlations between pretest NEUROPSI scores and reading ability were low. However, correlations between posttest NEUROPSI scores and reading scores were higher and significant for several subtests. Results are interpreting as supporting the assumption that reinforcement of those abilities in which illiterates significantly underscore results in a significant improvement in neuropsychological test scores and strongly facilitates the learning-to-read process. The NEUROALFA method of teaching reading to adult illiterates is beginning to be used extensively in Mexico. To our knowledge, this is the first attempt to apply neuropsychological principles to social problems.

Asunto(s)

Cognición/fisiología , Aprendizaje , Pruebas Neuropsicológicas , Evaluación de Programas y Proyectos de Salud , Lectura , Adolescente , Adulto , Escolaridad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Enseñanza

RESUMEN

The purpose of this research was to develop, standardize, and test the reliability of a short neuropsychological test battery in the Spanish language. This neuropsychological battery was named "NEUROPSI," and was developed to assess briefly a wide spectrum of cognitive functions, including orientation, attention, memory, language, visuoperceptual abilities, and executive functions. The NEUROPSI includes items that are relevant for Spanish-speaking communities. It can be applied to illiterates and low educational groups. Administration time is 25 to 30 min. Normative data were collected from 800 monolingual Spanish-speaking individuals, ages 16 to 85 years. Four age groups were used: (1) 16 to 30 years, (2) 31 to 50 years, (3) 51 to 65 years, and (4) 66 to 85 years. Data also are analyzed and presented within 4 different educational levels that were represented in this sample; (1) illiterates (zero years of school); (2) 1 to 4 years of school; (2) 5 to 9 years of school; and (3) 10 or more years of formal education. The effects of age and education, as well as the factor structure of the NEUROPSI are analyzed. The NEUROPSI may fulfill the need for brief, reliable, and objective evaluation of a broad range of cognitive functions in Spanish-speaking populations.

Asunto(s)

Cognición/fisiología , Pruebas Neuropsicológicas , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Escolaridad , Femenino , Humanos , Lenguaje , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , España

RESUMEN

Most of the tests, questionnaires, and neuropsychological batteries for the assessment of dementia have been translated and adapted for use in the Hispanic population without having normative data, which results in a high number of false positives when age and educational level are not considered. The Short Cognitive Performance Test (SKT) is a psychometric instrument evaluating memory and attention deficits that has been developed and standardized in Germany (Erzigkeit, 1989a, 1989b). The objective of this study was to adapt the SKT, to establish normative criteria that take into consideration age and educational level, and to establish its concurrent validity in comparison to other neuropsychological tests: Brief Neuropsychological Evaluation for Spanish-Speaking Subjects (Ostrosky-Solis et al., 1994), the Mini-Mental State Examination (Folstein et al., 1975), and the Blessed Functional Scale (Blessed et al., 1968) in 238 neurologically intact subjects and 97 subjects with mild to moderate dementia. The SKT showed adequate sensitivity (80.5%) and specificity (80.3%) in subjects with medium and high educational level; however, the sensitivity and specificity diminished (75% and 56.7%) in subjects with no education or low educational level. The adapted and validated version of the SKT in the Mexican population has been shown to be a psychometric instrument that in subjects with medium educational level can detect cognitive alterations and is able to determine the severity of deterioration; however, in subjects with low educational level and severe dementia, the SKT cannot be usefully administered.

Asunto(s)

Trastornos del Conocimiento/diagnóstico , Demencia/diagnóstico , Lenguaje , Encuestas y Cuestionarios , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/epidemiología , Demencia/epidemiología , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Valores de Referencia , Sensibilidad y Especificidad , España/epidemiología

RESUMEN

One hundred and five normal subjects from 20 to 89 years old, and with a minimum of six years of formal education were selected. Subjects were divided into seven age ranges, with 15 subjects in each group. The following tests were individually administered: (1) Wechsler Memory Scale (WMS) (Wechsler, 1945); (2) Serial Verbal Learning (Ardila, Rosselli & Puente, 1994; Ardila & Ostrosky, 1991); (3) The Rey-Osterrieth Complex Figure (ROCF) (Osterrieth, 1944) (copy, immediate, and delayed reproduction); (4) Corsi's blocks (Milner, 1971) (forwards and backwards); and (5) Rivermead Behavioural Memory Test (Wilson, Cockburn, & Baddeley, 1985). This last test may be considered as a functional or ecological memory test. All test scores declined across ages between 4.1% and 76.6%. In all the tests, excepting Digits, standard deviations increased with age. It was observed that the youngest subjects could retain about three-fourths of the information presented, whereas the oldest retained around one-third of this information. About half of the test significantly correlated with the Rivermead Behavioral Memory Test. A factor analysis revealed four different factors accounting for 63.3% of the variance. A single nonverbal memory factor accounted for over 40% of the variance.

Asunto(s)

Envejecimiento/psicología , Memoria/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Valores de Referencia

RESUMEN

The purpose of this study was to further analyze the effects of education across different age ranges on neuropsychological test performance. Two different analyses were performed. The first analysis was conducted in order to pinpoint the impact of school attendance on neuropsychological testing. A group of 64 illiterate normal subjects was selected in the Mexican Republic. Their performance was compared with two barely schooled control groups (1-2 and 3-4 years of schooling). The subjects' ages ranged from 16 to 85 years. In the second analysis, the illiterate subjects were further matched by age and sex with individuals with 1 to 4, 5 to 9, and 10 to 19 years of formal education. The Spanish version of the NEUROPSI neuropsychological test battery (Ostrosky, Ardila, & Rosselli, 1997) was used. Results indicated a significant educational effect on most of the tests. Largest educational effect was noted in constructional abilities (copying of a figure), language (comprehension), phonological verbal fluency, and conceptual functions (similarities, calculation abilities, and sequences). Aging effect was noted in visuoperceptual (visual detection) and memory scores. In the first subject sample, it was evident that, despite using such limited educational range (from 0-4 years of formal education), and such a wide age range (from 16-85 years), schooling represented a stronger variable than age. It is proposed that education effect on neuropsychological test performance represents a negatively accelerated curve, tending to a plateau.

RESUMEN

Subjects from four Mexican families at risk of inheriting Alzheimer's disease (AD) were studied using a complete neuropsychological battery. These tests were repeated and compared 1 year later. Some of the experimental subjects belong to an international protocol on molecular chromosomal study. A control group matched in age and schooling was included. The subjects at risk underwent a complete physical, neurological and neuropsychological assessment. A neuropsychological battery of cognitive domains designed for the the study of dementia syndromes was administered to all subjects. Six of the subjects showed abnormal performance in cognitive functions, memory, visuospatial functions or language which persisted 1 year later. The present work describes the initial findings of a long-term prospective study aimed at delineating the neuropsychological profile of subjects at risk and to validate subtle abnormalities which in some cases could be the incipient changes of AD.

Asunto(s)

Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Cognición , Pruebas Neuropsicológicas , Adulto , Enfermedad de Alzheimer/epidemiología , Atención , Depresión , Femenino , Humanos , Lenguaje , Masculino , Memoria , México , Persona de Mediana Edad , Linaje , Valores de Referencia , Factores de Riesgo , Percepción Espacial

RESUMEN

Research on aging processes have involved the study of evoked potentials. The last decades have witnessed increases in the study of the relationship between event related potentials and the brain's information processes. P300 has been widely studied to assess the neurophysiologic bases that underlie changes which take place during normal and physiologic aging settings. This study was aimed to establish normative data on the P300 component (latency and amplitude) in a Mexican population. One hundred and six (106) neurologically intact subjects, with ages ranging from 20 to 100 years were divided into seven groups. An electrophysiologic assessment using the classical paradigm to generate P300 was used. Monopolar registries referring to the auricular lobules and short circuiting in the Fz, Cz y Pz derivations while monitoring eye movements were used. ANOVA was used for analyzing the effects of age in the latency and the amplitude of both the N100 and P300 components for each one of the derivations. This analysis revealed statistically significant differences (p < 0.05) among the seven groups. The linear regression analysis showed an increase for each aging year in the 0.38 ms latency (r = 0.3804, p < 0.001) and a decrease in the 0.20 mV amplitude (r = 0.2036, p < 0.03). The normative data of the P300 component in the Mexican population studied yielded an objective reference for differential diagnosis and early detection of dementia disorders in patients belonging to a normal aging population.

Asunto(s)

Envejecimiento/fisiología , Potenciales Relacionados con Evento P300/fisiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales

RESUMEN

Based on the successful use of fetal striatal brain grafting in the restoration of striatal function in rat and nonhuman primate models of Huntington's disease, as well as on the evidence for the clinical potential of fetal brain grafting in the treatment of Parkinson's disease, homotopic fetal striatal homotransplantations were performed in two huntingtonians. Case 1 was a 37 year-old female with moderate to severe Huntington's disease of 9 years evolution; case 2 was a 29 year-old male with mild Huntington's disease of 5 years evolution. Using open microsurgery, each patient was implanted to the ventricular wall of the right caudate nucleus with both striata from a 13 week-old and a 12 week-old human fetus, respectively. Since surgery both patients were kept on cyclosporine A. Surgery produced no damaging effect to either patient. The time course of the neurological progression of their disease, spanning 33 months for case 1, and 16 months for case 2, reveal that the disease in both patients has progressed more slowly in relation to their preoperative state. Although presently it is not possible to determine to what extent, surgery has modified the course of their disease, or if it will continue to have an effect on it, these surgeries represent the first step towards the development of brain grafting for Huntington's disease.

Asunto(s)

Cuerpo Estriado/trasplante , Trasplante de Tejido Fetal , Enfermedad de Huntington/cirugía , Adulto , Animales , Modelos Animales de Enfermedad , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Linaje , Ratas , Trasplante Homólogo

RESUMEN

Fetal brain grafting has been used successfully in the restoration of striatal function in rat and non human primate models of Huntington's disease (HD). This is a report of the first clinical trial of this procedure applied to a 37 year old Mexican female with moderate to severe HD of 9 years evolution. The two striata from a 13 week-old human fetus were homotopically transplanted to 4 cavities in the ventricular wall of the right caudate nucleus. The months after surgery, her neurologic and neuropsychologic evaluations revealed the stabilization of many of her signs and most neuropsychologic parameters, a moderate improvement of her choreic movements, predominantly in the face, of her ability to define and express ideas in oral and written form, and of her articulatory agility, as well as of some activities of her daily life and social behavior. There was a slight deterioration of her gait and posture. Her saccadic system and optokinetic nystagmus, and her visuospatial and visuoperceptual functions were deteriorated.

Asunto(s)

Trasplante de Tejido Encefálico , Cuerpo Estriado/trasplante , Trasplante de Tejido Fetal , Enfermedad de Huntington/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Enfermedad de Huntington/fisiopatología , Examen Neurológico , Embarazo , Pruebas Psicológicas

RESUMEN

We report on the clinical status of 5 patients with Parkinson's disease (PD) 3 years after autologous adrenal medullary (AM)-to-caudate nucleus (CN) implantation, and of 2 PD patients, 2 years after fetal ventral mesencephalon (VM)- and fetal adrenal (A)-to-CN homotransplantation. Current clinical evaluation of 4 of the AM grafted patients revealed sustained bilateral amelioration of their PD signs, most notably of rigidity, postural imbalance and gait disturbances, resulting in a substantial improvement in their quality of life. The disease-related dystonia of one of them disappeared only 2 years after surgery. The levodopa requirements of 2 of these patients and the anticholinergic therapy of another have been reduced. In agreement with the satisfactory clinical evaluation of these 4 patients, their neuropsychological and electrophysiological improvements, initially registered 3 months after surgery, have been maintained for 3 years. After 1 year of significant recovery, the 5th patient of this group has almost returned to her preoperative state. The 2 homotransplanted patients also showed sustained bilateral improvement of their PD signs. Two years after surgery, the most improved signs of the fetal VM case were rigidity, bradykinesia, postural imbalance, gait disturbances and facial expression. The fetal A case has only shown amelioration of rigidity and bradykinesia. Neither of them has shown significant neuropsychological changes. Their current levodopa requirements are less than before surgery. The improvements shown here by PD patients after brain tissue grafts go beyond those obtained using any other therapeutic approach, when levodopa fails. Although more studies and the development of these procedures are obviously required, these initial human trials appear to be resisting the test of time.

Asunto(s)

Glándulas Suprarrenales/trasplante , Médula Suprarrenal/trasplante , Trasplante de Tejido Encefálico , Núcleo Caudado , Trasplante de Tejido Fetal , Mesencéfalo/trasplante , Enfermedad de Parkinson/cirugía , Glándulas Suprarrenales/embriología , Adulto , Terapia Combinada , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Levodopa/administración & dosificación , Levodopa/uso terapéutico , Masculino , Mesencéfalo/embriología , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico , Calidad de Vida , Índice de Severidad de la Enfermedad , Trasplante Autólogo

Asunto(s)

Médula Suprarrenal/trasplante , Trasplante de Tejido Encefálico , Trasplante de Tejido Fetal , Mesencéfalo/trasplante , Enfermedad de Parkinson/cirugía , Sustancia Negra/trasplante , Trasplante Heterotópico , Médula Suprarrenal/embriología , Trasplante de Tejido Encefálico/efectos adversos , Trasplante de Tejido Encefálico/métodos , Núcleo Caudado , Terapia Combinada , Femenino , Trasplante de Tejido Fetal/efectos adversos , Trasplante de Tejido Fetal/métodos , Estudios de Seguimiento , Humanos , Levodopa/uso terapéutico , Masculino , Mesencéfalo/embriología , México , Persona de Mediana Edad , Neurotransmisores/metabolismo , Evaluación de Procesos y Resultados en Atención de Salud , Enfermedad de Parkinson/tratamiento farmacológico , Sustancia Negra/embriología , Trasplante Heterotópico/efectos adversos , Trasplante Heterotópico/métodos

RESUMEN

We developed a neuropsychological battery for assessment of cognitive processes that was standardized in 150 neurologically intact subjects from different socioeducational levels in Mexico City (Ostrosky et al., 1985, 1986). The present study was designed to explore the capacity of this neuropsychological battery to discriminate a brain-injured population from a normal one. Thirty-four patients attending the neurological service of two hospitals institutions in Mexico City were studied. The reasons for going to the hospital included both neurological and neuropsychological symptoms. The group was divided into two subgroups: twenty-four patients who showed brain damage confirmed by brain scans, and ten patients with a normal brain scan. A control group of 19 normal subjects was also studied and paired with the other groups by sex, age and sociocultural level. The results show that the neuropsychological battery was able to recognize 83.3% of the patients with scanographically confirmed brain damage: the total percentage of successful diagnosis was 88.2% and there were no false positives. These results indicate that neuropsychological assessment is a powerful diagnostic procedure that also evaluates the patient's cognitive-behavioral activity and can help to predict the possibilities for rehabilitation and return to work.

Asunto(s)

Encefalopatías/diagnóstico , Trastornos del Conocimiento/diagnóstico , Pruebas Neuropsicológicas , Adulto , Encefalopatías/complicaciones , Encefalopatías/epidemiología , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/etiología , Femenino , Humanos , Masculino , México , Factores Socioeconómicos

RESUMEN

This work presents the long-term evolution (12-27 months) of the patients with adrenomedullary autotransplants to the caudate nucleus for the treatment of Parkinson's disease. Sixteen men and 6 women, mean age of 49.9 years, received brain implants of their own adrenal medulla using the procedure of Madrazo et al. (1). Nineteen of the transplanted patients suffered idiopathic Parkinson's disease and 3 of them parkinsonism. Before surgery 20 patients were on L-dopa and suffered collateral signs due to the drug. The degree of severity of their disease was evaluated pre and postoperatively, with and without medication, in their "on" and "off" periods, using the international scales of Schwab and England, Hoehn and Yahr, Madrazo, and the UPRS, and was documented by videotape. Biochemical analyses were made of lumbar and ventricular cerebrospinal fluid, and neuropsychological and neurophysiological evaluations were performed before and after surgery. In some patients, the location and viability of the adrenal medullary implants were demonstrated by brain scintigraphy using 131-I-metaiodobenzylguanidine, a chromaffin specific radiopharmaceutical. The clinical evaluations of 18 autotransplanted patients (4 died) showed their significant functional recovery both in their "on" and "off" periods, that for the first patients operated has remained stable for 27 months. Also, their response to L-dopa improved allowing the reduction of their postoperative doses of medication to 30% of their preoperative requirements, with the disappearance of the collateral effects of the drug.

Asunto(s)

Glándulas Suprarrenales/trasplante , Enfermedad de Parkinson/cirugía , Trasplante Heterotópico , Acetilcolinesterasa/metabolismo , Adulto , Anciano , Núcleo Caudado , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/líquido cefalorraquídeo , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/enzimología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/psicología , Complicaciones Posoperatorias , Cintigrafía , Factores de Tiempo

RESUMEN

The most prominent ERP to occur during intervals of preparation and anticipation is the contingent negative variation (CNV) or expectancy wave. The purpose of the study was to distinguish the characteristics of the CNV in a group of children with reading disabilities or dyslexia, and to compare it with a group of normal readers. Nine right handed boys aged between 9 and 13 years with reading disabilities were studied. The children were matched with a group of nine normal readers. Four derivations were used: F3, Cz, P3, and O1, with reference to linked ears. Data were analyzed using multivariate procedures. Significant differences between groups in the CNV amplitude at the left parietal site were observed. We discuss the participation of this zone and we consider processes like expectancy and attention in the differences observed.

Asunto(s)

Variación Contingente Negativa , Dislexia/fisiopatología , Electrofisiología , Adolescente , Niño , Potenciales Evocados , Humanos , Masculino

Asunto(s)

Daño Encefálico Crónico/diagnóstico , Pruebas Neuropsicológicas/métodos , Adulto , Daño Encefálico Crónico/psicología , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas

RESUMEN

The group selected for this evaluation consisted of 109 normal people with an average age of 25, coming from two different sociocultural levels (high and low) of Mexico City. All were completely evaluated by Luria's battery for neuropsychological assessment, adapted by Ardila, Ostrosky, and Canseco, 1981. This group of tests measures nine different areas: Motor Functions, Somatosensory Knowledge, Auditory Knowledge, Visuospatial Knowledge, Cognitive Processes, Language, Reading, Writing and Basic Calculations. For all of these, the higher performance standards were achieved by the subjects from the high sociocultural level. A significant interaction between sociocultural level and sex was observed. The differences between sexes appear only in subjects from the low sociocultural level. Factor analysis of the battery revealed that the most sensitive items to sociocultural level were those related on one hand, to the handling of complex structural and conceptual aspects of language and on the other hand, to the organization of motor sequences and in general motor programming. Research related to the differences found is reviewed and implications for clinical assessment are discussed.

Asunto(s)

Batería Neuropsicológica de Luria-Nebraska , Pruebas Neuropsicológicas , Adulto , Características Culturales , Femenino , Humanos , Masculino , México , Psicometría , Factores Socioeconómicos