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Alfredo Ardila

Publications and source records attributed to Alfredo Ardila.

16 recordsLinked to original sources
PubMed2006

Dysexecutive agraphia: a major executive dysfunction sign.

Different types of writing disorders associated with brain pathology have been described. Limited mention the writing disturbances associated with prefrontal pathology, however, is found. Clinical observations of patients not only with focal prefrontal pathology but also with other conditions affecting the frontal system (e.g., traumatic head injury, dementia) confirm the assumption that these patients present an overt decrease in the ability to express ideas in writing. It is proposed that complex aspects of writing, such as planning, narrative coherence, and maintained attention, are significantly disturbed in cases of impairments of executive functions. Frontal lobe patients not only have difficulties in keeping the effort required for writing, but also to organize the ideas in the written texts. The term dysexecutive agraphia is proposed to refer to this writing disorder. Three illustrative cases are presented. It is finally suggested that questions regarding the ability to write should be included in dementia questionnaires and executive functioning testing.

Adult↗
PubMed2006

Memory abilities in children with subtypes of dyscalculia.

This study examines (a) mathematical skills of 2 subgroups of children with developmental dyscalculia (DD)--1 group with DD only and a second group with DD plus reading disorders (RDD)-and (b) analyzes the memory skills of both groups of children. Fifty 11- and 12-year-old children were selected from public schools in Guadalajara, Mexico. Seventeen children had DD only, 13 had RDD, and 20 were normal controls. Testing included 10 calculation and 6 memory subtests taken from the Evaluación Neuropsicológica Infantil (Matute, Rosselli, Ardila, and Ostrosky, in press). Results indicated that children with DD and children with RDD show a similar pattern of mathematical impairment. Both subgroups had significantly lower scores than the control group in working memory tasks. In addition, the RDD group had significantly lower scores than the control group in visual learning and semantic memory. Although the RDD group scored lower than the DD group in most memory tests, this difference did not reach significance. Working memory tests (digits backwards and sentence repetition) appeared to be the best predictors of mathematical test scores and may represent a major cognitive defect in children with specific defects in mathematics.

Aptitude↗
PubMed2005

Cultural values underlying psychometric cognitive testing.

It is proposed that culture (values, beliefs, styles of behavior) can affect neuropsychological testing. Cognitive testing represents a social situation that-as any social situation, it is one governed by implicit cultural rules. At least eight different culture-dependent values underlie cognitive testing: (1) One-to-one relationship, (2) Background authority, (3) Best performance, (4)Isolated environment (5) Special type of communication, (6) Speed, (7) Internal or subjective issues, and (8) The use of specific testing elements and strategies. In addition, it is proposed that"the distance" (e.g., gender, age, ethnicity) between the examiner and the examinee may potentially impact the testing situation. A special analysis regarding the function of instruction in cognitive tests is also presented emphasizing that test instruction interpretation is also culture-dependent. Some potential avenues of research are finally proposed.

Cognition Disorders↗
PubMed2005

The influence of the parents' educational level on the development of executive functions.

Information about the influence of educational variables on the development of executive functions is limited. The aim of this study was to analyze the relation of the parents' educational level and the type of school the child attended (private or public school) to children's executive functioning test performance. Six hundred twenty-two participants, ages 5 to 14 years (276 boys, 346 girls) were selected from Colombia and Mexico and grouped according to three variables: age (5-6, 7-8, 9-10, 11-12, and 13-14 years), gender (boys and girls), and school type (private and public). Eight executive functioning tests taken from the Evaluacion Neuropsicologica Infantil; Matute, Rosselli, Ardila, & Ostrosky, (in press) were individually administered: Semantic Verbal Fluency, Phonemic Verbal Fluency, Semantic Graphic Fluency, Nonsemantic Graphic Fluency, Matrices, Similarities, Card Sorting, and the Mexican Pyramid. There was a significant effect of age on all the test scores and a significant effect of type of school attended on all but Semantic Verbal Fluency and Nonsemantic Graphic Fluency tests. Most children's test scores, particularly verbal test scores, significantly correlated with parents' educational level. Our results suggest that the differences in test scores between the public and private school children depended on some conditions existing outside the school, such as the parents' level of education. Implications of these findings for the understanding of the influence of environmental factors on the development of executive functions are presented.

Adolescent↗
PubMed2004

HUMANS: An English and Spanish neuropsychological test battery for assessing HIV-1-infected individuals--initial report.

A neuropsychological battery for testing HIV-1-infected individuals in Spanish was developed. We refer to this battery as the HIV/University of Miami Annotated Neuropsychological test battery in Spanish (HUMANS). The HUMANS battery includes recommendations of the National Institute of Mental Health Neuropsychology Workgroup on HIV-1 infection and measures processes in the following 7 cognitive domains: attention, verbal and visual memory, information processing speed, abstraction and executive functioning, language, visuospatial and visuoconstructive, and motor. Administration requires approximately 3 to 4 hr. The English version of the battery is sensitive to HIV-1 serostatus and Centers for Disease Control clinical disease stage. We report on the test selection, translation, and adaptation of this parallel English battery into Spanish using methods to eliminate linguistically and culturally biased items in some tests. The importance of standardized neuropsychological instruments equivalent in different languages to test HIV-1-positive individuals for impairment is emphasized. Validation and reliability studies are in progress.

Cognition Disorders↗
PubMed2004

Verbal and nonverbal fluency in Spanish-speaking children.

Fluency measures are commonly used in clinical developmental neuropsychology to assess executive functions. Little is known about the effect of age on performance in these tests. This article analyzes the effect of age on measures of verbal (semantic and phonologic) and nonverbal (semantic and nonsemantic) fluency in 171 children (81 boys, 90 girls) between ages 6 and 15. Participants were selected from public and private schools in Guadalajara and Tijuana, Mexico. A significant age effect was found on all tests but no interaction between age and type of test was found. Significant correlations among the 4 fluency tasks ranged from.36 to.46. Results are consistent with the findings of normative studies carried out in other countries and support the cross-language validity of verbal fluency tests.

Adolescent↗
PubMed2003

The impact of culture and education on non-verbal neuropsychological measurements: a critical review.

Clinical neuropsychology has frequently considered visuospatial and non-verbal tests to be culturally and educationally fair or at least fairer than verbal tests. This paper reviews the cross-cultural differences in performance on visuoperceptual and visuoconstructional ability tasks and analyzes the impact of education and culture on non-verbal neuropsychological measurements. This paper compares: (1) non-verbal test performance among groups with different educational levels, and the same cultural background (inter-education intra-culture comparison); (2) the test performance among groups with the same educational level and different cultural backgrounds (intra-education inter-culture comparisons). Several studies have demonstrated a strong association between educational level and performance on common non-verbal neuropsychological tests. When neuropsychological test performance in different cultural groups is compared, significant differences are evident. Performance on non-verbal tests such as copying figures, drawing maps or listening to tones can be significantly influenced by the individual's culture. Arguments against the use of some current neuropsychological non-verbal instruments, procedures, and norms in the assessment of diverse educational and cultural groups are discussed and possible solutions to this problem are presented.

Adult↗
PubMed2003

Nongenetic factors as modifiers of the age of onset of familial Alzheimer's disease.

OBJECTIVE: The purpose of this research was to identify environmental and personal factors that could be related to the variability in the age of onset of familial Alzheimer's disease (FAD) (36-62 years). METHODS: A sample was taken of 49 subjects with FAD and with the mutation E280A in the presenilin-1 gene on chromosome 14; the sample was divided into two subgroups: 27 individuals with age of onset of the disease between 36 and 46 years (early onset) and 22 individuals whose disease began between 47 and 62 years (late onset). Information on environmental and personal factors was collected by means of a questionnaire answered by the patients if their clinical condition allowed it, or by their relatives; such information was organized in a categorical way. Comparisons between the two groups for each categorical variable were done by means of the chi-square test. Noncollinear variables that showed statistical significance were included as independent variables in a logistic regression analysis to predict their association with early onset of the disease. RESULTS: Only 5 of the 140 studied variables were different between the two groups in univariate analysis: education, surgical history, type of stressful event, depression, and affective losses. The logistic regression model was constituted by education, depression, and affective losses. High-level education had approximately 15 times more probability of association with an early onset of the disease; both the history of affective losses and depressive symptoms had 4 times more probability of a similar association. CONCLUSIONS: The association of high-level education and early onset of the disease could be related to an earlier detection of symptoms, in turn determined by greater intellectual and environmental demands. The occurrence of depression and affective losses has been considered a prodromic manifestation of the disease. Our findings are evidence of high clinical heterogeneity even in a genetically homogeneous group.

Adult↗
PubMed2003

Acalculia: an fMRI study with implications with respect to brain plasticity.

We report the case of a 44-year-old right-handed man with severe acalculia and 4 normal age-matched controls. The acalculia patient had magnetic resonance findings of a wedge shaped defect in the left posterior temporal-parietal cortex, involving the angular gyrus, and a lacunar infarct of the right thalamus. Functional magnetic resonance exams were performed utilizing four tasks consisting of serial subtracting by sevens, basic calculation, complex calculation, and abstract calculation. Both patient and controls showed specific task-related activation with some differences that may indicate brain plasticity, even though no significant recovery in calculations abilities was observed in the patient.

Adult↗
PubMed2003

Progressive agraphia, acalculia, and anomia: a single case report.

A case of a 50-year-old, right-handed female, mono-lingual native Spanish-speaker with a university-level education and cognitive changes is reported. Over approximately 2 years, she presented with a progressive deterioration of writing abilities associated with acalculia and anomia. An MRI disclosed a left parietal temporal atrophy. Two years later, further significant cognitive decline consistent with a dementia of the Alzheimer's type was observed. Amnesia, executive dysfunction, and ideomotor apraxia were found. Writing was severely impaired, and some difficulties in reading were observed. Copying abilities, however, were relatively well preserved, and the patient could drive and go to different city locations without significant spatial orientation difficulties. A second MRI approximately 2 years later showed that brain atrophy had progressed significantly. Spontaneous writing and writing to dictation were impossible. The ability to read words was preserved, but the ability to read pseudowords was lost. Changes in calligraphy were noted. This case clearly illustrates the progression of focal cognitive defects over time and the spread of abnormalities to other domains.

Agraphia↗
PubMed2002

Stroop effect in Spanish-English bilinguals.

The aim of this study was to analyze the performance of Spanish-English bilinguals on the Golden Stroop Test. The effects of bilingualism, participants' age, age of acquisition of the second language, and proficiency in each language were analyzed. Participants consisted of 71 Spanish-English bilinguals, 40 English monolinguals, and 11 Spanish monolinguals from South Florida. Proficiency in Spanish and English was established using a self-report questionnaire and the English and Spanish versions of the Boston Naming Test. In bilinguals, the Golden Stroop Test was administered in English and in Spanish. Overall, performance was slower in bilinguals than in monolinguals. No significant differences were observed in color reading but bilinguals performed worse in the naming color condition. Even though bilinguals were 5% to 10% slower in the color-word condition, one-way ANOVAs revealed no statistically significant differences between groups. Within the bilingual group, the Stroop Test scores were similar in both English and Spanish. Age of acquisition of the second language did not predict the Stroop Test performance. Repeated measures ANOVA demonstrated a significant interaction between Language Proficiency x Language (in which the test was administered) in some of the ST conditions. In balanced bilinguals, the language used in the ST did not matter, but in unbalanced subjects, the best-spoken language showed better results. In addition, our results support the presence of both between- and within-language interference in Spanish-English bilinguals. Different conceptualization models of the structure of bilingual memory are disclosed.

Adult↗
PubMed2002

Houston Conference: need for more fundamental knowledge in neuropsychology.

Two training models in neuropsychology have been recently proposed (Guidelines of the INS-Division 40 Task Force on Education, Accreditation, and Credentialing, Clin. Neuropsychol. 1: 29-34, 1987; Hannay, H. J. et al., Anh. Clin. Neuropsychol. 13: 157-250,1998). When comparing both educational models, similarities but also differences are found. According to the Houston Conference model--but not to the former model--neuropsychology represents a specialty of psychology. In the Houston Conference training model, applied knowledge is overtly emphasized, whereas fundamental or basic knowledge in neuropsychology appears weak. The proposed program does not seem to provide sufficient emphasis and background knowledge in (1) History of neuropsychology, (2) Neuropsychological syndromes, and (3) Neuropsychology theory.

Credentialing↗
PubMed2002

Acalculia and dyscalculia.

Even though it is generally recognized that calculation ability represents a most important type of cognition, there is a significant paucity in the study of acalculia. In this paper the historical evolution of calculation abilities in humankind and the appearance of numerical concepts in child development are reviewed. Developmental calculation disturbances (developmental dyscalculia) are analyzed. It is proposed that calculation ability represents a multifactor skill, including verbal, spatial, memory, body knowledge, and executive function abilities. A general distinction between primary and secondary acalculias is presented, and different types of acquired calculation disturbances are analyzed. The association between acalculia and aphasia, apraxia and dementia is further considered, and special mention to the so-called Gerstmann syndrome is made. A model for the neuropsychological assessment of numerical abilities is proposed, and some general guidelines for the rehabilitation of calculation disturbances are presented.

Animals↗
PubMed2002

A cross-linguistic comparison of verbal fluency tests.

The aim of this study was to compare oral fluency strategies of Spanish-English bilinguals in Spanish and English with Spanish and English monolinguals when given either phonemic (alphabetical) or semantic categorical cues. The use of grammatical words (words that play a grammatical function relating words within a sentence) or content words (words that have a meaning such as nouns, verbs, and adjectives) in the alphabetical categories is analyzed. This study also addresses the relation between productivity and the use of a semantic strategy to organize responses. Eighty-two right-handed participants (28 males and 54 females) with a mean age of 61.76 (SD = 9.30; range 50-84) and a mean educational level of 14.8 years (SD = 3.6; range 2-23) were selected. Forty-five of the subjects were English monolinguals, 18 were Spanish monolinguals, and 19 were Spanish-English bilinguals. Oral verbal fluency was tested asking subjects to generate words within phonemic (F, A, and S) and semantic (animals) categories. In the phonemic condition, performance of English and Spanish monolinguals was similar. Bilinguals produced significantly fewer words than English monolinguals in the categorical semantic condition but not in the phonological condition. In the phonological condition, English monolinguals generated significantly more grammatical words than Spanish monolinguals, and bilinguals produced a significantly higher number of grammatical words in English than in Spanish. Animal subcategories and semantic associations were similar in both languages for all groups. Results were discussed in terms of crosslinguistic differences in the recall of alphabetical words.

Aged↗
PubMedDate not supplied

Language representation and working memory with bilinguals.

Working memory (WM) plays a crucial role in learning a second language (L2). The ability to repeat words in an unknown language has been observed to predict success in learning that language. Conversely, decreased digit span and inability to repeat pseudowords have been related with failure in L2 acquisition. Not only digit span, but also "word span" and "semantic span" should be considered in WM analysis. In addition to the phonological system, a semantic system is proposed in the WM model for language. In bilinguals, brain activation patterns during WM tasks have been observed to be more complex when using a L2. Processing information in L2 is more demanding, and WM may be less efficient. It can be conjectured that language understanding defects in L2 are at least partially due to this decreased efficiency of WM in its phonological as well as in its semantic subsystem. The reader will be introduced to the basic assumptions of WM. It will be emphasized that WM is significantly involved in the ability to learn a L2. Cross-linguistic differences in digit span will be analyzed. It will be concluded that despite digit span and word span are affected by different variables, "semantic span" may be similar across languages. Words in a L2 function as low frequency words, and hence, semantic search takes longer and WM is less efficient. It will be concluded that in addition to the "phonological system," the WM model should include a "semantic system," involving a "semantic store" and a "semantic search" process.

Humans↗