Biomedical subjects

J Narbona-García

Publications and source records attributed to J Narbona-García.

4 recordsLinked to original sources

PubMed1999

[Specific disorders in the language development: neurobiological basis].

Studies of twins, familial aggregates and particular phenotypic conditions have shown an inherited basis for some dysphasias or specific developmental language impairments (SLI). This predisposition is usually multifactorial but the analysis of some families allows to postulate an autosomal dominant transmission of deficits in specific modular aspects of linguistic competences. Moreover, neuroimaging studies have shown modifications of normal volumetric interhemispheric asymmetries, and in group of SLI with receptive prominent disorder coexist epileptiform activity in wakefulness and non-REM sleep EEG; in some of these cases, antiepileptic drugs, specially steroids, can significantly ameliorate the language processing. As many patients with SLI have a difficulty for discrimination of subtle temporal indices, a hypothesis can also be made of a dysfunction in various subcortical structures (thalamus, basal ganglia, cerebellum) modulating the cerebral cortex in phonological processing.

Aphasia↗

PubMed1999

[Neurobiology of attention deficit-hyperactivity disorder].

This is a review of current relevant evidences concerning the nature and pathophysiological mechanisms of attention deficit hyperactivity disorder (ADHD). From a neuropsychological point of view, clinical symptoms seem to arise from an early dysfunction of the executive system. Patients with ADHD have deficits in inhibitory control, cognitive flexibility, working memory and self-motivation, and all of them account for the attentional deficit in non automatic information processing. Decrease in prefrontal, caudate and pallidal structures, which sustain the executive function, have been found in neuroimaging volumetry. Cognitive evoked potentials obtained during attentional tasks have augmented latencies and abnormal topography. A dopaminergic deficit in the structures sustaining executive function is postulated from the results in experimental animal models and from functional neuroimaging studies in patients, and this seem to be the foundation of the favorable outcome with psychostimulants in correctly diagnosed patients. Psychopedagogic interventions are necessary to help the patient in order to get an optimal internal locus of control, which is necessary for attention and impulsiveness inhibition, and also for compensation of associated disorders.

Attention Deficit Disorder with Hyperactivity↗

PubMed1994

Neuropsychological evaluation of children with intracranial tumors: impact of treatment modalities.

Antineoplastic treatment has a deleterious effect on intellectual functions, which is mainly attributable to radiotherapy. With the object of determining the neuropsychological disturbances associated with brain irradiation in the child, and to try to differentiate them from the effects caused by the other types of treatment (surgical and chemotherapy) as well as from the effects of the tumor itself, a cross-sectional study was carried out in 25 survivors of medial edge intracranial tumors. In order to monitor the effect of systemic chemotherapy on the cognitive functions, and the effect of prolonged absence from school, two control groups were formed, one made up of subjects treated with chemotherapy for extracranial tumors, and the other of patients with non-malignant chronic disease. Neuropsychological functions were measured using the Spanish version of the Wechsler scale, as well as the following tests: Spreen-Benton, ITPA and TALE scales, Yuste Memory Test, Thurstone Attention Test, and the Rey Complex Figure. In addition to a progressive decline found in the full scale intelligence quotient in children irradiated for intracranial tumors, variance analysis showed that these patients deteriorate mainly in visual attention and memory, but also significantly in verbal fluency and in the Performance Intelligence Quotient and all its subtests, when compared to the control groups. Visual attention and the Wechsler Picture Arrangement and Block Designs, were the tests whose decline correlated with the total radiation administered. The article relates this specific neuropsychological injury with the total brain irradiation dose but also with the structures located in the cone-down fields of irradiation to boost regions in the middle edge intracranial content.

Adolescent↗

PubMed1993

Neuropsychological outcome of children after radiotherapy for intracranial tumours.

With the aim of determining the neuropsychological disturbances associated with cranial radiotherapy in the child, a cross-sectional study was carried out on 25 survivors of medial-edge intracranial tumours. Children irradiated for intracranial tumours experienced deterioration mainly in visual attention and memory, but also in verbal fluency, full-scale IQ, and performance IQ and all its subtests, compared with control groups. This deterioration progressed with time, finally involving at least abstract thought and verbal skills. The pattern of damage by irradiation varied according to the degree of brain maturity, therefore the younger the child at irradiation, the greater the decline in IQ and visual-constructive abilities, and the earlier the deterioration of visual memory and verbal skills.

Adolescent↗