Implicit Motor Sequence Learning in Children With Learning Disabilities: Deficits Limited to a Subgroup With Low Perceptual Organization

Children with developmental dyslexia showed greater sleep disturbances than controls, including problems initiating and maintaining sleep

AIM

Although there have been frequent clinical reports about sleep disturbances in children with learning disabilities, no data are available about the prevalence of sleep disturbances in children with developmental dyslexia (DD). This study evaluated sleep disturbances in children with DD referred to a hospital clinic and compared their scores with healthy controls.

METHODS

We consecutively enrolled 147 children (66% male) aged 10.26 ± 2.63 years who were referred by clinical paediatricians to the Clinic for Child and Adolescent Neuropsychiatry at the Second University of Naples with DD and 766 children without DD (60% male) aged 10.49 ± 2.39 years recruited from schools in the same urban area. Sleep disturbances were assessed with the Sleep Disturbances Scale for Children (SDSC), which was filled out by the children's main carers.

RESULTS

Compared with the controls, the children with DD showed significantly higher rates of above threshold scores on the total SDSC score (p < 0.001) and on the subscales for disorders in initiating and maintaining sleep (p < 0.001), sleep breathing disorders (p < 0.001) and disorders of arousal (p < 0.001).

CONCLUSION

Sleep disorders were significantly more frequent in children with DD than in healthy controls. A possible relationship between dyslexia and sleep disorders may have relevant clinical implications.

Occlusal traits in developmental dyslexia: a preliminary study

AIM

The objective of the study reported here was to assess the orthodontic features in children affected by developmental dyslexia (DD).

PATIENTS AND METHODS

A total of 28 children affected by DD (22 boys, six girls; mean age: 9.78 ± 1.69 years) were compared with 51 healthy children (38 boys, 13 girls; mean age 9.41 ± 1.48; range 7-10 years). Reading and writing skills were evaluated along with orthodontic features.

RESULTS

The DD and control groups were not significantly different in terms of total intelligence quotient (P = 0.441) and writing skills (P = 0.805 and P = 0.240, respectively), whereas significant differences were observed between the DD group and control group in both word reading (2.018 ± 1.714 vs 0.917 ± 0.563; P = 0.000) and non-word reading (2.537 ± 1.543 vs 0.862 ± 0.244; P = 0.000). Moreover, for many orthodontic features, there was no significant difference between the two groups; only in prevalence of diastemas (57.14%, P = 0.006), midline diastemas (46.42%, P = 0.007), overbite > 4 mm (71.42%, P = 0.006) and overjet > 4 mm (53.57%, P = 0.001), was there a statistically significant difference. According to univariate logistic regression analysis, the presence of diastemas (odds ratio [OR] 4.33; 95% confidence interval [CI] 1.61-11.65), midline diastemas (OR 4.68; 95% CI 1.61-13.43), an overbite >4 mm (OR 1.75; 95% CI 0.64-4.71), or an overjet >4 mm (OR 2.76; 95% CI 1.06-7.20) seems to play a role in the relationship between occlusal abnormalities and DD in children.

CONCLUSION

Children with DD tend to present with altered dental features, particularly in the area of the incisors, suggesting that a persistently different tongue kinematic profile may thus affect both the developmental variability of the tongue and lip and the occlusion.