PubMed HealthSearch

Biomedical subjects

T Benke

Publications and source records attributed to T Benke.

8 recordsLinked to original sources

High-speed memory scanning in Parkinson's disease: adverse effects of levodopa.

High-speed memory scanning as assessed by the Sternberg paradigm was studied in 12 nondemented patients with fluctuating Parkinson's disease and 13 age-matched healthy controls. Patients were first assessed before taking their morning dose of levodopa ("off") and again after that dose had produced full clinical effect ("on") after that dose had produced full clinical effect ("on"). Although motor components of the measured choice reaction time were slower in patients when off than in control subjects, memory scanning speed was not different. After levodopa (on), patients' motor time normalized, but cognitive processing speed became significantly slower when compared with previous performance in the off condition and with controls. Contrary to previous concepts of bradyphrenia in patients with Parkinson's disease, these results indicate that dopaminergic stimulation can reduce cognitive processing speed.

Frontal Lobe

Effects of treatment with trihexyphenidyl on cognitive function in early Parkinson's disease.

13 patients with PD of recent onset underwent a series of neuropsychological tests for frontal lobe associated functions (Sternberg paradigm, WCST, CVLT) before and during treatment with Artane. Test results at baseline were not significantly different from those of an age-matched control group (n = 13). Retesting after a mean of 2 weeks' treatment with trihexyphenidyl revealed only slight impairment in CVLT while performance on the other tests remained unchanged.

Adult

Neuropsychological deficits in asymptomatic carotid artery stenosis.

A total of 20 subjects with asymptomatic carotid artery stenosis (ACAS) and a group of healthy controls were compared as to their cognitive performance. Subjects with ACAS showed substantial deficits on tasks of mental speed, learning, visuospatial abilities, verbal processing and deductive reasoning. The cognitive profile of ACAS--subjects indicated non-specific impairment, possibly related to widespread cerebral vascular disease, of which the presence of ACAS may be one indicator.

Brain Ischemia

[Speech changes in dementia].

This review analyzes the spectrum of language deficits commonly encountered in dementia. A specific communication profile is found in dementia of the "cortical" type, such as Alzheimer's disease. With advancing disease lexical, comprehension and pragmatic functions deteriorate, whereas syntax and phonology tend to be preserved. This pattern bears some resemblance to aphasia types like transcortical and Wernicke's aphasia, however, a much broader range of communicative functions is impaired in Alzheimer's disease than in aphasia. Differentiation of dementia and aphasia, especially in elderly patients requires careful neuropsychological assessment of language, memory and other psychological functions. "Subcortical" dementia commonly presents with dysarthria as the leading symptom and linguistic impairment is rarely of crucial importance until late stages. Thus, the interetiologic dissociation of language and speech impairment can be used for dementia differentiation. Aphasia batteries are not sufficient to comprehend the range of language deficits in demented patients. Testing the communication impairment in dementia requires specific tasks for spontaneous speech, naming, comprehension, reading, writing, repetition and motor speech functions. Tasks for verbal learning and metalinguistic abilities should also be performed. Language deficits are frequent initial symptoms of dementia, thus language assessment may be of diagnostic relevance. Many data support the concept that the communication deficit in dementia results from a particular impairment of semantic memory.

Aged

Sex equality in intrahemispheric language organization.

Sex differences in inter- and intrahemispheric cerebral organization, found in previous studies, have been used to explain sex differences in cognitive abilities. This study highlights data to contradict such widely held beliefs. Intrahemispheric language organization was examined by determining the location of lesions causing aphasia by computed tomography. No sex differences in the incidence of anterior, posterior, or central lesions was found. The distribution of left-hemisphere lesions in stroke patients, with or without aphasia, was also equal among the sexes. This study does not support the postulated gender difference in intrahemispheric cerebral organization.

Anomia

Coronary reactive hyperaemia and coronary dilator action of adenosine during intracoronary infusion of angiotensin II.

Investigations were carried out in chloralose-anesthetized, thoracotomized dogs. The effects of an intracoronary infusion of angiotensin II (3 ng/ml coronary blood) on reactive hyperaemic blood flow and adenosine-induced coronary vasodilation were established. Coronary artery occlusions were performed over periods of 5, 10 and 25 heart beats and adenosine was injected intracoronarily at dosages of 2, 4, and 8 microgram/kg body weight. The vasodilator effect of adenosine and reactive hyperaemia after 10 and 25 heart beats were both significantly diminished by angiotensin II. By contrast, reactive hyperaemia after coronary artery occlusion lasting 5 heart beats remained unchanged. The present results obtained with angiotensin II further confirm that adenosine is only partially involved in mediating reactive hyperaemia and that this involvement takes place only after sufficiently long periods of coronary artery occlusion.

Adenosine