Biomedical subjects

A Ardila

Publications and source records attributed to A Ardila.

At least 55 records · Page 3Linked to original sources

PubMed1994

An epidemiologic study of stuttering.

A questionnaire designed to assess the prevalence of stuttering and its relation with: (a) central nervous system risk factors; (b) associated disorders (allergies, migraine-type headache, developmental dyslexia history, smoking, and drug abuse), and (c) depression symptoms, was given to a general population sample of 1879 Spanish-speaking university students (mean age = 24.0). A prevalence of 2% of self-reported stuttering was found. Results indicated that the prevalence of minor brain injury or dysfunction, developmental dyslexia history, word-finding difficulties, and depressive symptoms was higher among the self-reported stutterers than among the nonstutterers.

Adolescent↗

PubMed1994

Spatial alexia.

Twenty-one patients with right hemisphere damage were studied (11 men, 10 women; average age = 41.33; range = 19-65). Patients were divided in two groups: pre-Rolandic (six patients) and retro-Rolandic (15 patients) right hemisphere damage. A special reading test was given to each patient. The observed errors included: literal errors (substitutions, additions, and omissions of letters), substitutions of syllables and pseudowords for meaningful words, left hemispatial neglect, confabulation, splitting of words, verbal errors (substitutions, additions, and omission of words), grouping of letters belonging to two different words, misuse of punctuation marks, and errors in following lines. It was proposed that spatial alexia is characterized by: (1) some difficulties in the recognition of the spatial orientation in letters; (2) left hemispatial neglect; (3) tendency to "complete" the sense of words and sentences; (4) inability to follow lines when reading texts, and sequentially explore the spatial distribution of the written material; and (5) grouping and fragmentation of words, most likely as a consequence of the inability to interpret the relative value of spaces between letters correctly.

Adult↗

PubMed1994

Spatial acalculia.

Twenty-one patients with right hemisphere damage were studied (11 men, 10 women; average age = 41.33; range 19-65). Patients were divided into two groups: pre-Rolandic (six patients) and retro-Rolandic (15 patients) right hemisphere damage. A special calculation test was given. Different types of calculation errors were analyzed. Spatial alexia and agraphia for numbers, loss of calculation automatisms, reasoning errors, and general spatial defects interfering with normal number writing and reading, were observed. Number processing was impaired, whereas the calculation system was partially preserved. Fact retrieval and procedural difficulties were observed, but arithmetical rules were properly used. It is concluded that calculation abilities in right hemisphere damaged patients are disrupted as a result of: (1) visuospatial defects that interfere with the spatial arrangement of numbers and the mechanical aspects of mathematical operations: (2) inability to recall mathematical facts and appropriately to use them; and (3) inability to normally conceptualize quantities and process numbers.

Adult↗

PubMed1994

Cognitive impairments in adolescent drug-abusers.

A basic neuropsychological test battery was given to 64 adolescents (57 males and seven females; mean age = 15.5) divided in two groups: (1) drug-abusers ("experimental group," n = 26), and (2) non drug-abusers ("control group," n = 38). Psychoactive substances included marijuana, "crack," solvent inhalation, gasoline sniffing, and alcohol. The following tests were used: (1) language, (2) perceptual recognition, (3) memory, and (4) praxic abilities. In general, performance was mildly (but nonsignificantly) lower in the experimental than in the control group. Only some neuropsychological test scores correlated with lifetime and amount of psychoactive drugs used. It was proposed that cognitive impairments in this sample of young drug-abusers may have been not evident because: (1) lifetime use was limited, due to the age of the subjects; and (2) in adolescents and pre-adolescents, toxic effects of drug-abuse might be manifested as a decrease in the rate of cognitive development rather than as a general cognitive decline.

Adolescent↗

PubMed1993

Spatial agraphia.

Twenty-one patients with right hemisphere damage were studied (11 men, 10 women; average age = 41.33; age range 19-65). Subjects were divided into two groups: pre-Rolandic (6) and retro-Rolandic (15) right hemisphere damaged patients. A special writing test was given to each patient. The writing errors observed included literal substitutions, feature omissions and additions, letter omissions and additions, inability to maintain horizontal writing, inappropriate grouping and fragmentation of elements, and changes in handwriting style. Associated disorders included left-hemiparesis, visual field defects, spatial hemi-neglect, constructional apraxia, spatial alexia, and spatial acalculia. It is proposed that spatial agraphia is related to: (1) left hemi-neglect, (2) constructional deficits, (3) general spatial defects, and (4) some motor disautomatization and tendency to perseverate. In cases of right frontal damage, motor-associated deficits (iterations of features and letters) predominated, whereas in cases of posterior right hemisphere damage, spatial defects (inappropriate distribution of written material in the space, grouping of letters belonging to different words, and splitting of words) were more evident. Writing impairments are in general more noticeable in cases of retro-Rolandic damage.

Adult↗

PubMed1993

Language deviations in aphasia: a frequency analysis.

Thirty right-handed left hemisphere-damaged patients were taken and divided into five groups (transcortical motor, Broca, conduction, Wernicke, and anomic aphasia). Language deviations were scored and analyzed for the Picture Description (Plate No. 1, The Cookie Theft), Repetition (Words, High and Low Probability Sentences), and Naming (Responsive Naming, Confrontation, and Body-part naming) subtests of the Boston Diagnostic Aphasia Examination--Spanish version (Goodglass & Kaplan, 1979). A classification of paraphasias is proposed. Language deviations were scores for the following groups: Literal paraphasias (phoneme omissions, additions, displacements, and substitutions), verbal paraphasias (formal, morphologic, semantic, and unrelated), syntagmatic paraphasias, circumlocutions (object description and instrumental function), indefinite anaphors, and neologisms. Frequency of different types of language deviations is presented in the five aphasia groups. It was found that some paraphasic errors appeared in several aphasia groups; others were characteristics of specific aphasic syndromes.

Adolescent↗

PubMed1993

Handedness in native Amazonians.

A sample of 65 Tucano adolescents living in the Amazon region of Colombia were administered a 26-item handedness questionnaire. All subjects were right-handed. A factor analysis of the data indicated a factor structure rather different from that seen in North Americans, although both skilled and unskilled handedness factors were seen. Other factors related to specific tool use and to strength. These data indicate that positive reinforcement for right-hand use can modify patterns of handedness, and may well alter the relations among different items. The data suggest that hand preference can be modified through positive reinforcement at an appropriate age, and that hand preference is the precursor of skill differences rather than vice versa.

Adolescent↗

PubMed1993

Toward a model of phoneme perception.

Hemisphere asymmetry in phoneme perception was analyzed. Three basic mechanisms underlying phoneme perception are proposed. Left temporal lobe would be specialized in: (1) ultrashort auditory (echoic) memory; (2) higher resolution power for some language frequencies; and (3) recognition of rapidly changing and time-dependent auditory signals. An attempt was made to apply some neurophysiological mechanisms described for the visual system to phoneme recognition in the auditory system.

Brain↗

PubMed1992

Phonological transformations in conduction aphasia.

Different explanations and subtypes of conduction aphasia are analyzed. Characteristics of literal paraphasias in parietal-insular conduction aphasia are discussed, emphasizing that paraphasias in conduction aphasia are articulatory-based (articulatory literal paraphasias) and due mainly to phoneme substitutions and phoneme deletions; they result basically in switches in phoneme manner and place of articulation. Similarities between errors in ideomotor apraxia and conduction aphasia language deficits are presented. It is proposed that language deviations (in oral as in written language) in conduction aphasia can be understood as a segmentary apraxia of speech.

Aphasia, Wernicke↗

PubMed1992

A comparative analysis of functional status among Spanish- and English-speaking patients with dementia.

The assessment of functional capacity is regarded as an important part of a comprehensive diagnostic work-up for dementia. However, there is a paucity of data regarding comparative functional performance among different ethnic/cultural groups. In this study, we compared Spanish- and English-speaking dementia patients and normal controls on a comprehensive functional assessment battery administered within the clinical setting. Despite equivalent levels of cognitive impairment, Spanish-speaking dementia patients evidenced more difficulties on certain functional tasks relative to their English-speaking counterparts. On the other hand, Spanish- and English-speaking controls did not differ with regards to their functional performance. Results suggest that the extent of deterioration in specific functional subskills may be related to the degree to which they have been overlearned and practiced. Further, they indicate the potential utility of direct functional assessment in both Spanish- and English-speaking populations.

Activities of Daily Living↗

PubMed1992

Luria's approach to neuropsychological assessment.

A. R. Luria's approach to neuropsychological assessment was examined. Three basic points of departure from Luria are presented: his interpretation of cognitive activity as functional systems, his emphasis on the individualized approach, and the importance of the analysis of the errors. A distinction was introduced between Luria's neuropsychological testing, and Luria's neuropsychological approach; the former refers to the specific set of neuropsychological tests Luria used and developed and the latter, to the specific clinical use of these tests. It is emphasized that Luria's basic contribution to assessment in neuropsychology, refers to the clinical approach he proposed and developed. Problems related to the normalization and validity of neuropsychological tests are analyzed. It is concluded that different approaches in neuropsychological assessment are related to the specific goals for which neuropsychological assessment is performed.

Humans↗

PubMed1991

Errors resembling semantic paralexias in Spanish-speaking aphasics.

Forty-one Spanish-speaking left-hemisphere-damaged patients were selected and divided into seven groups (transcortical, Broca's aphasia, conduction aphasia, Wernicke's aphasia, anomic aphasia, alexia without agraphia, and global aphasia). A reading battery composed of eight different subtests was given to each patient (reading of letters, reading of syllables, reading of pseudowords, reading of words, reading of sentences, understanding commands, reading and comprehension of texts, and logographic reading). Different types of reading errors were analyzed. Only in the logographic reading subtest were some word-recognition errors found, resembling semantic paralexias. It is proposed that semantic paralexias in English (and other languages) depend upon the partial logographic nature of the reading system. The importance of cross-linguistic analysis of reading errors, taking into account reading system idiosyncracies, is emphasized.

Adult↗

PubMed1991

Scopolamine intoxication as a model of transient global amnesia.

In Colombia (South America) during recent decades the administration of scopolamine, extracted from plants belonging to the Datura or Brugmansia genus, has become an important neurologic and toxicologic phenomenon. These extracts have been popularly known as "Burundanga." Chemical characteristics and clinical features of scopolamine intoxication are described. Anterograde amnesia and submissive behavior found in patients intoxicated with scopolamine are analyzed. Burundanga intoxication is related to other toxic phenomena found in different countries and similitudes with transient global amnesia are emphasized.

Adult↗

PubMed1991

Neuropsychological deficits in chronic cocaine abusers.

A basic neuropsychological assessment battery was given to thirty-seven chronic freebase cocaine ("crack") abusers. The following tests were used: Wechsler Memory Scale (Wechsler, 1945), Rey-Osterrieth Complex Figure (Osterrieth, 1944) (copy and immediate reproduction), Verbal Fluency (semantic and phonologic), Boston Naming Test (Goodglass, Kaplan, & Weintrab, 1983), Wisconsin Card Sorting Test (Heaton, 1981) and Digit-symbol from the WISC (Wechsler, 1974). In general, performance was lower than expected according to their age and educational level. Subjects showed significant impairment in short-term verbal memory and attention subtests. Neuropsychological test scores were correlated with lifetime amount of cocaine used, suggesting a direct relationship between cocaine abuse and cognitive impairment. A pattern of cognitive decline is proposed.

Adult↗

PubMed1990

Neuropsychological assessment in illiterates. II. Language and praxic abilities.

A basic neuropsychological examination of language and praxic abilities was administered to extreme educational groups (100 illiterates and 100 professionals). Subjects were matched according to sex and age (16-25, 26-35, 36-45, 46-55, and 56-65). The following tasks were included: language comprehension, phonological discrimination, naming (objects, figures, and body parts), repetition of words, verbal fluency, calculation, buccofacial and ideomotor praxis, finger alternating movements, meaningless movements, cancellation task, coordinated movements with both hands, and motor impersistence tasks. All the differences between the two educational groups were statistically significant. Two of the eight language tests (phonological discrimination and naming figures) and three of the seven praxic tests (buccofacial praxis, coordinated movements, and cancellation task) showed differences between age groups with a better performance in the younger groups. Calculation tasks and ideomotor praxis showed differences between sexes with a better performance in males. Influence of educational factors in performing routine neuropsychological tests is analyzed.

Adolescent↗

PubMed1990

Normative data on the Boston Diagnostic Aphasia Examination in a Spanish-speaking population.

Normative data of the Boston Diagnostic Aphasia Examination (Goodglass & Kaplan, 1972) in a Spanish-speaking population is presented. This test was given to 180 neurologically normal adults grouped according to three variables: sex, age, and educational level. The statistically significant differences found are presented. Few differences appeared between sexes, but there were marked differences among the different age groups and in particular among educational levels. A correction to the scoring is proposed for each of the subtests according the patient's educational level.

Adolescent↗

PubMed1990

Is there a cognitive marker in major depression?

The purpose of this study was to compare adolescents' response pattern on specific visual tasks during acute and recovered states of depression. Twenty-three inpatient adolescents with unipolar depression were tested before and four weeks after treatment. Twenty control subjects matched in age, sex, handedness, and intelligence were tested at similar intervals. Measures included four visual spatial tasks: the Gestalt Street Completion Test, the Judgment of Line Orientation, the Hooper Visual Organization Test and the Rey-Osterrieth Complex Figure. Overall, the results indicated that depressed adolescents performed significantly more poorly than controls in all four measures during both pre-and posttest conditions. They demonstrated greatest difficulty in measures of Gestalt Closure and Judgment of Line Orientation. However, the Gestalt Closure task was the only one to be correlated to severity of depression. These findings are discussed in the light of previous research suggesting a right hemisphere dysfunction and the existence of a cognitive marker in affective disorders.

Adolescent↗

PubMed1989

Phonological transformations in Spanish-speaking aphasics.

Thirty-seven aphasic patients whose native language is Spanish were divided into four groups: (1) Broca's, (2) Wernicke's, (3) Conduction, and (4) Anomia. Phonological errors produced on repetition and object-naming tasks were analyzed in terms of type of transformation and degree of similarity between target and errors in terms of shared distinctive features. Segmental transformations were of the following types: (1) pure substitution, (2) pure addition, (3) deletion, (4) reduplicative addition (doublet creation)--anticipatory (right to left) or preservative (left to right), (5) reduplicative substitution (doublet creation)--anticipatory or perseverative, and (6) mutual exchanges. Pure substitutions were the most prevalent, exchanges, the least. Some error types were found to differentiate significantly between aphasic populations. We suggest that different mechanisms may underlie the same error type for different aphasic populations.

Adult↗