Search PubMed⌕ Search

Biomedical subjects

G Denes

Publications and source records attributed to G Denes.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Physiology, psychology and pathology of writing and spelling--an overview].

Writing and spelling are conceived as concerted actions comprising cognitive planning, motor action and an expressive content. In literate societies the individual use of alphabetic systems is acquired immediately after speech as a "cultural technique". As such these systems demand specific cognitive and motor skills which have been analysed primarily on the basis of neurological and psychiatric syndromes. We distinguish primary developmental disturbances and secondarily acquired disturbances of writing and spelling, categorizing the latter into four essential disturbance areas: linguistic command, motor execution, automatism control and dynamic tonus regulation. The clinical significance of writing and spelling is not confined to its possible disturbances. In pathologically induced restrictions of cognitive functions or of social skills the fact is rather that the written language frequently contributes to the development of individual coping strategies. From the psychodynamic aspect, written communication is characterized principally by its proximity-regulating function.

Handwriting↗
PubMed1994

Concepts and facts in calculation.

A patient is described who is affected by an inability to recall and use 'arithmetical facts' of one-digit multiplications and divisions. This loss contrasts with the preservation of a wide set of complex notions that the patient exploits in order to overcome his deficit and get the right result. This observation helps in isolating and describing an important component of arithmetical long-term memory that is not overlearnt and the functioning of which is not automatic or mechanistic. An account of such a component is lacking in models of arithmetic currently referred to in cognitive neuropsychology. In a remediation study, performed over several weeks, the effect of training was selective for each single arithmetical fact: not even skills with multiplication complements (e.g. 6 x 3, 3 x 6) fully benefited from the rehabilitation of a specific fact. This suggests that the storage format of each fact is independent from that of other facts.

Cerebrovascular Disorders↗
PubMed1992

Reading aloud in jargonaphasia: an unusual dissociation in speech output.

A patient is described who showed several dissociations between oral and written language processing after bilateral retrorolandic vascular lesion. Dissociation was firstly between abolished auditory comprehension and preserved written comprehension and then involved confrontation naming, clearly superior in the written modality. The third striking dissociation involved oral output; spontaneous speech, although fluent and well articulated, consisted of neologistic jargon, while reading aloud was clearly superior though not perfect. Data are discussed with reference to a cognitive model of word processing. The pattern of dissociation in word production may be due to a failure in retrieving the phonological word form from the semantic system.

Aged↗
PubMed1991

A specific deficit for numbers in a case of dense acalculia.

In this study we investigated the acalculic condition of a patient, C.G., with the classical signs of Gerstmann's Syndrome: finger agnosia; right-left disorientation; a profound agraphia (but with an equally profound alexia) and a remarkably dense acalculia. Using a series of number processing and number knowledge tasks, a selective impairment for numbers was demonstrated. Within the category of numbers C.G. showed a largely preserved ability to deal with numbers below 4, in all tasks and in all modalities, while she was totally unable to deal with numbers above 4. The consistency of responses and the ineffectiveness of cueing indicated that numbers above 4 were lost, rather than hard to access. Further testing showed that this impairment did not result from a more general semantic memory problem, a difficulty in understanding quantities or a deficit in reasoning abilities thought to underlie the concept of numbers. Difficulty with some other ordinal structures was also present, but appeared unrelated to those affecting numbers.

Female↗
PubMed1990

Italian Multicentre Study on Dementia (SMID): a neuropsychological test battery for assessing Alzheimer's disease.

For the Italian Multicentre Study on Dementia, a longitudinal survey on Alzheimer's disease (AD) initiated in 1982, we developed a neuropsychological test battery for screening, staging and monitoring cognitive impairment in AD patients and for delineating their pattern of cognitive decline. The tests measured higher cortical functions primarily involved in AD, such as short- and long-term memory, orientation, language, and praxis, and spanned a large enough range of difficulty to minimize ceiling and floor effects. We administered this battery to 143 clinically diagnosed AD patients and 146 hospital controls whose scores were corrected for age and educational level. Interrater and test-retest reliability were substantial, as were content and concurrent validity. Five of the battery's subtests proved capable of accurately screening early demented from non-demented elderly subjects and of staging mild, moderate, severe and very severe mental impairment. The mean performance of subjects classified into these categories differed significantly on all cognitive functions tested. Follow-up studies are in progress.

Aged↗
PubMed1990

Autobiographical memory loss and confabulation in Korsakoff's syndrome: a case report.

A patient with Korsakoff's syndrome is presented, who showed a selective loss of Autobiographical Memory along with a preserved Semantic Memory. Confabulations were a prominent feature. They only involved Autobiographical Memory and were persistent in time and consistent in content. The implications of these findings for understanding the nature of Autobiographical Memory impairment are discussed.

Alcohol Amnestic Disorder↗
PubMed1990

An unusual case of perseveration sparing body-related tasks.

A patient who, following left occipital and posterior callosal lesion, showed a massive pattern of perseveration with sparing of body related tasks is described. It is thought that such dissociation would reflect independence of body related tasks at the level of internal representation.

Aged↗
PubMed1989

Impaired grating discrimination following right hemisphere damage.

We investigated the effect of unilateral brain lesions on visual discrimination of low-, middle- and high-frequency gratings. The performance of patients with right hemisphere lesions was significantly impaired compared with that of both controls and patients with left hemisphere lesions. This impairment was largely limited to patients with right posterior hemispheric lesions and was present with all spatial frequencies. These findings run counter to the hypothesis that high and low spatial frequencies are preferentially processed by different hemispheres.

Adult↗
PubMed1989

When a patient can write but not copy: report of a single case.

A dissociation between spared spontaneous and impaired writing on copy is described in a patient with severe limb and constructional apraxia. Visual-perceptual abilities were normal as well as oral language and reading. The findings are discussed in the light of an information processing model of writing.

Aged↗
PubMed1989

Impairment in processing meaningless verbal material in several modalities: the relationship between short-term memory and phonological skills.

Phonological processing abilities were studied in a patient who, following focal brain damage, showed selective impairment in non-word reading, writing, and repetition and also a severe short-term memory (STM) deficit specific for auditorily presented verbal material. The patient could execute tasks involving phonemic manipulation and awareness perfectly. Our data, in contrast with earlier observations in a case of developmental phonological dyslexia, show that acquired impairment in non-word reading, writing, repetition, and immediate memory may occur despite good phonological processing abilities. The role of STM in processing meaningless verbal material is discussed.

Adult↗
PubMed1988

Acquired stuttering: a motor programming disorder?

Acquired stuttering (AS) can follow unilateral right, left or bilateral hemispheric lesion, and can, but not necessarily, coexist with aphasia. In this paper we experimentally tested motor programming skills in a patient with AS of vascular origin. Motor programming consists in the structuration of the whole sequence of response prior to the onset of the first response element of a sequence of responses. Chronometric studies have shown that the time to initiate a sequence of manual responses is a function of the characteristics of the forthcoming sequence of responses. In our patient, reaction times involving single motor responses performed by right hand were within normal limit. On the contrary, when the task required a sequence of motor responses, there was a consistent difficulty in following the sequence: moreover, in the few correct sequences, reaction time analysis showed a lack of motor programming. It is suggested that AS could be the speech epiphenomenon of a more generalized disturbance of motor programming.

Cognition Disorders↗
PubMed1986

The role of the right hemisphere in processing negative sentences in context.

Given a pattern consisting of x1, x2,..., xn similar elements and y1, which is perceived as different from the former, it is more plausible to assert that y is not x rather than to assert that x is not y (Wason, J. verb. Learn verb. Behav. 4, 7-11, 1965). In order to appreciate such a difference, the entire set has to be considered. Right-hemisphere brain-damaged patients were submitted to a series of visually presented patterns, each pattern consisting of seven similar items and one dissimilar item. Their task was to complete a statement referring to a single element of each pattern. Statements were either simple affirmative or negative sentences. Errors and reaction times were recorded. Patients with a right-hemisphere injury were found to be insensitive to the plausible-implausible dimension in completing negative sentences. It is hypothesized that right-hemisphere brain-damaged patients are less adequate in this task because they are less capable in putting each element into the visual context.

Aged↗
PubMed1986

Oral and written language in a case of childhood phonemic deafness.

Neuropsychologic and neurolinguistic studies performed on an 11-year-old Landau-Kleffner boy are reported. At age 3 his language began to deteriorate progressively until complete disappearance. At the same time, the patient developed epileptic seizures. When 6 years old, he was taught to match objects to the corresponding written word, and subsequently he was able to learn reading and writing to such extent that he could attend primary school. BAER and primary cortical auditory responses were normal, whereas late cortical components were grossly retarded and distorted. Phonemic discrimination, identification, and production were absent, and in contrast, lexical-semantic abilities tested through reading and writing were normal. In visual STM tasks, phonologic mediation was absent. The role of phonologic mediation in language acquisition is then hypothesized.

Child↗
PubMed1984

Discrimination and identification of emotions in human voice by brain-damaged subjects.

Discrimination and identification of emotions in human voice was studied in normal controls and in 4 groups of brain-damaged subjects, subdivided along the right/left and anterior/posterior dimensions. Results showed a failure of right-brain-damaged patients, the right posterior group being significantly worse than all the other groups. Qualitative differences emerged as well: both a conceptual and an acoustic deficit seem to contribute to right posterior patient performance.

Aphasia, Broca↗
PubMed1982

Difficulty in reaching objects and body parts: a sensory motor disconnexion syndrome.

A 19-year-old woman is described who, following an acute episode of eclampsia during pregnancy, displayed a complex neuropsychological syndrome. Along with a mild pattern of conduction aphasia, she showed a severe apraxia, total agraphia, marked constructional disturbances and was unable to reach targets outside and on her body and to perform accurate motor tasks under visual, tactile and proprioceptive control. These symptoms are discussed as the results of a disconnexion syndrome and related to the C.T. scan findings.

Adult↗
PubMed1982

Unilateral spatial neglect and recovery from hemiplegia: a follow-up study.

A follow-up study was undertaken in order to investigate the outcome of recovery from right and left hemiplegia on simple motor function and activities of daily living. The role of concomitant neurophysiological deficits was also investigated. The main results indicate that after six months from onset, left hemiplegics show a lesser degree of improvement in independence and social adjustment coupled with a tendency to a poorer recovery of motor function than the corresponding group of right hemiplegics. Unilateral spatial neglect, which is more frequent and severe in the group of left hemiplegics, seems to be crucial in hampering their performance.

Activities of Daily Living↗
PubMed1982

Role of the frontal lobes on an attention task: a signal detection analysis.

Sensitivity and criterion were studied on an attention task requiring detection of new stimuli for a group of 20 patients with unilateral hemispheric damage restricted to the anterior or posterior areas. Patients performed a simple attention task, in which the presence of a novel stimulus had to be detected against the repetition of the same stimulus repeated. Only the site of the lesion (anterior vs posterior damage) influenced the performance of the task. In fact, frontal patients had both lower capacity to discriminate between signals and nonsignals and lower confidence in their responses.

Attention↗