The International journal of neuroscience
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Randomized Controlled Trial Comparative Study Clinical Trial
Electrophysiological indicants of black-white discrimination performance for letter and non-letter patterns.
This study examined event-related potentials (ERPs) and behavioral measures, considered to be sensitive to the selective processing of black versus white letter and non-letter patterns, in a group of seventy-four randomly selected 6 to 8 year old children. Results demonstrated faster and more accurate behavioral performance on the experimental task for the letter than for the non-letter patterns. ⋯ Later ERP measures (200-260 and 500-600 ms post-stimulus) in response to the letter stimuli showed greater differences as a function of task relevance over the left than over the right hemisphere. The results from the present study indicate a remarkably early facilitative influence of stimulus type (letter versus non-letter patterns) on the luminance discrimination of these stimuli and are consistent with an overlap of linguistic and perceptual processing.
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Classical Maple Syrup Urine Disease (MSUD) is a disease of infancy which is an inherited disorder of metabolism of branched-chain amino acids (BCAA). The BCAA are normally transaminated to branched-chain keto acids (BCKA). However, the enzyme required to metabolize the BCKA is deficient, resulting in elevation of both, the BCAA and the BCKA. ⋯ These studies and a review of the literature suggest that one component of the pathophysiological mechanism for the acute neurotoxic effects in this disorder is related to a defect in glutamate, glutamine and gamma-aminobutyric acid (GABA) production. The BCAAs are transaminated to BCKAs. Further metabolism of the BCKAs are blocked because of enzyme deficiency required for decarboxylation.(ABSTRACT TRUNCATED AT 400 WORDS)
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The right and left temporal lobes differ from each other with respect to the rate of intrauterine growth, the timing of maturation, rate of aging, anatomical organization, neurochemistry, metabolic rate, electroencephalographic measures, and function. These functional differences between the temporal lobes underlies the different patterns of psychopathology and endocrine reproductive disturbances noted in patients with temporolimbic epilepsy. The right hemisphere has greater limbic and reticular connections than the left. ⋯ To investigate this hypothesis, the prevalence of PC on CT scan was studied in a sample of 70 patients (43 men, 27 women, mean age: 29.2 years, range 9-58; SD = 10.1) with complex partial seizures, of whom 49 (70.0%) had a right temporal lobe focus. PC was present in 51 patients (72.8%) and was unrelated to any of the historical and demographic data surveyed. In the patients with a focus in the right temporal lobe, PC was present in 46 cases (93.8%) as compared to 5 of 21 patients (23.8%) with left temporal lobe foci.(ABSTRACT TRUNCATED AT 250 WORDS)
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The analgesic effects induced by two different kinds of peripheral conditioning stimulations, electroacupuncture (EA) and transcutaneous electrical nerve stimulation (TENS), were compared in the rat using the latency of radiant heat-evoked tail flick reflex as nociceptive index. The parallel elevations of withdrawal latency of tail flick were produced by EA and TENS administrations at the acupoints of S36 and Sp6 with low intensity (1-2-3 mA) and one of three different frequencies (2, 15 and 100 Hz). Analgesic effects of EA or TENS were characterized by slow-on and slow-off nature, and a significant linear correlation was found between both at any one of three frequencies. ⋯ Tolerance to EA stimulation with one of three frequencies reduced the corresponding frequency TENS-induced analgesia and vice versa. These data indicate that: (a) there is no significant difference in producing antinociception for two different peripheral conditioning stimulations when applied at the same sites and (b) the common neural mechanisms most likely process the analgesic effects of EA and TENS. The involvement of (an) endogenous opiate mechanism in the management of different frequency EA and TENS analgesia is discussed in detail.