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T Harmony

Publications and source records attributed to T Harmony.

60 records · Page 4Linked to original sources
PubMedDate not supplied

Computer tomography in children with electrophysiological abnormalities.

A computed tomography examination was carried out in a group of 43 children, of whom 15 had learning disabilities (LD). Children were selected with electrophysiological abnormalities in the routine EEG, in the quantitative EEG analysis and/or in the visual cortical and auditory brainstem evoked responses. Seven children, 1 control and 6 LD, had abnormalities in the computed tomography. The most frequent localization of the lesion was the left temporal lobe. This localization might explain the origin of the learning disorder, since the left temporal lobe is involved in reading and writing processes. There was a great concordance between the anatomical localization of the lesion by the computed tomography and the place of electrical abnormalities in the quantitative EEG and the visual evoked responses. These results strongly support the indication of a computed tomography examination in LD children.

Adolescent↗
PubMedDate not supplied

EEG coherences in patients with brain lesions.

EEG coherence between all pairwise combinations of the 10/20 system was studied in two groups: control subjects and patients with space-occupying brain lesions. Coherence was separately computed for the delta, theta, alpha and beta bands. Comparisons between both groups showed highly significant differences in all bands. In the patients with lower coherence values, these differences were mainly in the alpha band. When intra-hemispheric coherences between controls and patients with left hemispheric lesions were compared, significant differences were observed only in the left hemisphere. Comparisons between controls and patients with lesions in the right hemisphere also showed significant differences only in the injured hemisphere. In patients, paired t tests between the values of the intra-hemispheric coherence in the left hemisphere and the corresponding values in the right hemisphere demonstrated that lower coherences were confined to the damaged hemisphere. Our conclusion is that in the presence of lesions disrupting cortex and adjacent white matter the coherence between this area and the remaining cortical areas is lower than normal due to impairment of the fibers that connect the damaged area with the rest of the brain.

Adolescent↗
PubMedDate not supplied

[Visual somatosensory and auditory evoked potentials in multiple sclerosis].

In a group of 15 patients with multiple sclerosis and in a control group of 20 healthy subjects visual evoked potentials produced with flashes or checkerboard pattern, auditory evoked potentials after stimulation with three different tones, and somatosensory evoked potentials after stimulation of the left, right or both median nerves, and reactions to stroboscopic stimulation at seven different frequencies were investigated. Recording was done with unipolar leads from frontal, central, occipital and temporal regions on the left and right side. In patients with multiple sclerosis the cortical responses to all these stimuli had lower amplitude than in healthy subjects, and the reponses to stroboscopic stimulation were also abnormal in the group of patients. Different clinical signs related to various defects of sensory functions showed a high correlation with electrophysiological anomalies. Non-linear discrimination analysis was carried out using 13 variants (the amplitudes were calculated from peak to peak and correlation coefficients were calculated between identical regions on the left and right side) comparing the group of patients with the control group. Using this method it was possible to establish the correct diagnosis in all cases of multiple sclerosis and 85% of healthy subjects could have been included into the asymptomatic group. Since the methods used in these investigations are easy and can be easily automated the authors think that they could be very useful in the clinical diagnosis of multiple sclerosis.

Acoustic Stimulation↗