Down Syndrome Research and Practice 3(3)
Twenty-six adolescents and young adults with Down syndrome and 26 IQ- and CA-matched youth with other causes of intellectual impairment (comparison group) repeated a battery of audiological and auditory-cognitive tests on three annual assessments. Audiological tests revealed the following differences between the group with Down syndrome and the comparison group: a) Poorer acuity and longitudinal declines at each frequency from 250-8000 Hz for the group with Down syndrome, particularly at the highest frequencies; b) A tendency for the middle ear problems of Down syndrome individuals to be bilateral, chronic, and to reflect no mobility, retraction, or reduced mobility of the tympanic membrane; and c) Poorer reception and discrimination of speech in the group with Down syndrome. Correlational analyses revealed the following reliable relationships between performance on audiological and auditory-cognitive tests: a) individuals with Down syndrome who had lower speech discrimination scores, poorer acoustic reflexes, or bilaterally impaired tympanograms repeated spoken sentences less accurately; b) individuals with Down syndrome who had lower speech discrimination scores performed more poorly on a language comprehension task; and c) individuals with Down syndrome with impaired hearing (regardless of how it was measured) identified fewer spoken words when the words were rapidly followed by a masking noise or made discriminable by brief consonant sounds. It was suggested that poorer performance by hearing-impaired subjects with Down syndrome on auditory-cognitive tasks may have been due to an interaction of lower auditory acuity and slower processing speed. Also, because relationships between hearing and cognitive variables were not present in the comparison group, it was tentatively suggested that hearing loss may be more detrimental to cognitive abilities in intellectually impaired individuals with Down syndrome.
Joanna Nye, John Clibbens, and Gillian Bird
The aims of this study were to investigate the relationship between numerical and general ability and the contribution that receptive language makes to numerical ability in children with Down syndrome. Sixteen children with Down syndrome were tested on the following measures: two nonstandardised tests of numerical ability, two standardised numerical tests, two measures of receptive language and an IQ scale. Only one of the sixteen children attained a score on the IQ measure so the relationship between general and numerical ability in this population could not be assessed. All four numerical measures significantly correlated (positively) with each other, and receptive grammar (but not vocabulary) was found to significantly correlate (positively) to numerical skills. Details of the children's performance on the two main numerical measures under investigation are presented.
Glynis Laws, John MacDonald, Sue Buckley, and Irene Broadley
Children with Down syndrome who had followed a memory training programme were reassessed three years later. The programme, which involved training rehearsal and organisation strategies to improve short term memory, had resulted in significant gains on tests of auditory and visual memory skills. These gains were maintained for at least eight months after the end of the training period. However, after three years, memory capacity was found to have declined, although word spans were still significantly greater than those found before the training programme began. By comparing the performance of the children in the follow-up study with an untrained group matched for age, vocabulary and grammar understanding, it was concluded that this increase could be attributed to developmental progress and not to any residual effects of training. None of the children had continued to practice the memory training routines resulting in the loss of the trained memory skills over time.
This article reports on the effectiveness of an intervention programme designed to improve the morpho-syntax used by teenagers with Down syndrome in their speech. The intervention used reading to teach the language. All but one of the teenagers were using longer, more complex sentences, in their conversation at the end of the year's training. The extent of individual progress was significantly related to speech production ability and comprehension of grammar at the start of the year. Future language intervention programmes should focus on both phonology and grammar.