In the present study, sleep characteristics in reading disabled (RD) children were recorded to examine suggested relationships among sleep, maturational and cognitive processes. Subjects were thirty-nine 8-10 year old boys (15 controls (Cs), M = 9.2, SD = 0.6 yrs; 24 RD, M = 9.0, SD = 0.5 yrs, (Boder criteria)). Reading disabled children were classified as: (a) dysphonetic (N = 8; (auditory-sequential processing deficits)); (b) dyseidetic (N = 8; (visual-simultaneous processing deficits)); or (c) nonspecific (N = 8; (absence of cognitive impairments)). Sleep was recorded in the laboratory for four consecutive nights (2 adaptation, 2 baseline) using standard polysomnography. All groups exhibited variations across nights reflecting adaptation to the sleep laboratory, although these seemed attenuated in the RD subtypes relative to the Cs. Group comparisons (with nights 3-4 collapsed) were undertaken between Cs and: (1) RD children pooled into one group; and, (2) the three RD subtypes. Relative to the Cs, RD children showed: (1) more stage 4 sleep (p .009); (2) less REM sleep (p .02); (3) an extended initial NREM cycle (p .009), composed of greater absolute amounts of stages 2 (p .03) and 4 (p .005); and, (4) a longer REM onset latency (p .009), also composed of more minutes of stages 2 (p .05) and 4 (p .003). Subtype analyses revealed that differences in REM sleep, initial NREM cycle duration and REM onset latency were largest among Cs and nonspecifics (p .05; p .05; p .01, respectively). Eye movement density (EMD) analyses revealed that, with the exception of the initial REM period, in which the RD children (pooled) exhibited higher mean values than the Cs (p .05), no significant group differences were noted over all REM periods, across the first 4 REM periods or for each individual REM period. The sleep profile observed in RD children, (the nonspecifics in particular), was characterized by a significantly extended initial NREM cycle with increased amounts of stage 4 sleep. This may reflect the influence of an underlying maturational delay, which decreases the functional quality of stage 4 sleep, resulting in a decelerated restitution process in RD children. The overall absence of differences between groups in EMD suggest that the presence or nature of its relationship to information processing in RD children remains unclear. The subtype differences observed were not expected, given Boder's description of the nonspecific subtype and suggest that her interpretation of the behavioral profile of these children may need revision.
| Identifer | oai:union.ndltd.org:uottawa.ca/oai:ruor.uottawa.ca:10393/7728 |
| Date | January 1992 |
| Creators | Mercier, Lise. |
| Publisher | University of Ottawa (Canada) |
| Source Sets | Université d’Ottawa |
| Detected Language | English |
| Type | Thesis |
| Format | 182 p. |
Page generated in 0.0016 seconds