Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endogenous P300 and exogenous slow vertex potentials were obtained with tone and speech stimuli in a group of five children using a cochlear implant (CI) with poor speech recognition (group A) and compared with those from another group of five children using a CI with good speech recognition (group B). The responses were also compared to those of children with normal hearing (n= 14) and a group of adult CI users (n=9). N1 and P2 latencies of CI group A and group B were prolonged compared to those of normally-hearing children. In group A, P300 was present when contrasts with tone stimuli were used. When speech stimuli were used, P300 potentials were absent or delayed. P300 potentials obtained in group B were no different from those obtained in normally-hearing children. It is suggested that the poor results evoked with speech stimuli in contrast to those evoked with pure-tone stimuli in group A are due to the immaturity of (sub) cortical generators associated with acoustical and phonetic processing. In contrast to the children in group B, all children in group A suffered from congenital deafness.
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PMID:Evaluation of cochlear implant benefit with auditory cortical evoked potentials. 1240 11

Behavioral indices and ERP parameters were analyzed in 5-6 years old children who were shown a previously unseen set of fragmented drawings of familiar objects. Within this set, each object was represented by a series of drawings of different degree of fragmentation. It is found that children of 5-6, when compared to 7-8 years old children, are capable to recognize less fragmented drawings. In these children, no increase was found in N350-400 prefrontal negativity and late positive complex, otherwise a typical feature of mature recognition involving executive control. A comparison of ERP for recognized vs. unrecognized stimuli showed a significant increase in P300 and N400 amplitude over the right occipital area. A key feature of children of this age is a lack of significant difference between ERP to recognized vs. unrecognized stimuli over extrastriatal cortex (T5/T6) which is the crucial structure for recognition of fragmented objects via integration of their sensory features. The data we obtained suggest that both executive control immaturity and insufficient involvement of the ventral visual system constitute a specifics of recognition in children of 5-6.
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PMID:[Neurophysiological mechanisms of recognition fragmented images in 5 to 6-year-old children]. 2233 23