Sentence memory of individuals with Down's syndrome and typically developing children.
BACKGROUND
Individuals with Down's syndrome (DS) have an auditory short-term memory span disproportionately shorter than the non-verbal mental age (MA). This study evaluated the Baddeley model's claim that verbal short-term memory deficits might arise from slower speaking rates (and thus less material rehearsed in a 2 s passive store) by using the sentence memory subtest of the Stanford-Binet. Previous work had shown digit span recall speaking rate to be comparable to the examiner's slow rate (one syllable per second) for both DS and language-matched participants.


METHODS
Thirty individuals with DS were compared to two control groups [non-verbal MA-matched and mean length of utterance (MLU)-matched] on the sentence span and speaking rate for the longest verbatim recalled sentence. Sentence stimuli were presented at a normal speaking rate.


RESULTS
The DS group had shorter sentence memory span than the MA-matched group and a faster, rather than slower, speaking rate (syllables per second) than the MLU-matched controls.


CONCLUSIONS
Language production level accounted for a substantial portion of the variance in the sentence memory span in the DS group. Thus, language production skill, rather than speaking rate, predicts variability in verbal memory span.
Seung
H-K
HK
University of Florida, Gainesville, FL, USA. hkseung@hp.ufl.edu
Chapman
R
R
D000293:Adolescent; D000328:Adult; D001288:Attention; D001309:Auditory Threshold; D002648:Child; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007360:Intelligence; D008297:Male; D008570:Memory, Short-Term; D011939:Mental Recall; D010700:Phonetics; D011594:Psychometrics; D012016:Reference Values; D012660:Semantics; D013067:Speech Perception; D013195:Stanford-Binet Test / Q000706:statistics & numerical data; D014705:Verbal Behavior; D014706:Verbal Learning