The aim of this study is the assessment of maturational changes of median long-latency somatosensory evoked potentials (LL-SEP) components using mapping procedure in 11 normal and 19 congenital hypothyroid school-age children. The hypothyroid group was subdivided in 3 subgroups: 5 patients detected by a screening program (group A), 6 not screened presenting neurological and intellectual deficits (group B), and 8 without deficits (group C). In normal children P40 showed latency, morphology and scalp topography similar to adults, while N60 had a more anterior distribution. In all children P100 was better expressed over the parietal region contralateral to the stimulated side: in adults it is usually bilaterally distributed and only few cases present a clear lateralization. The main negative component was only in some cases N140, as observed in adults: some subjects had a predominant N260 with a typical central distribution. Moreover, in normal cnildren P300 was always greater than P200. Absolute and interpeak latency increases of LL-SEP components were present in the hypothyroid group, mostly in subgroups A and B. The maps showed in 31% of the patients a significant reduction, usually diffuse, of LL-SEP waves, particularly the later components. In group B, the frequency of alterations reached 66.7%. Our results suggest that childhood maturation of the somatosensory system is not yet completed, and abnormalities are present in pathological conditions proportional to cognitive impairment.
|Number of pages||8|
|Publication status||Published - 1992|
- brain mapping
- somatosensory evoked potentials
ASJC Scopus subject areas
- Clinical Neurology