Verbetering van visueel–motoriese integrasie by 6– tot 8–jarige kinders met Aandaggebrekhiperaktiwiteitsindroom / van Wyk J.
The visual system and good ocular motor control play an important role in the effective development of gross motor, sport, fine motor and academic skills (Erhardt et al., 1988:84; Desrocher, 1999:36; Orfield, 2001:114). Various researchers report a link between ocular motor problems and attention–deficit hyperactivity disorder (ADHD) (Cheatum & Hammond, 2000:263; Farrar et al., 2001:441; Gould et al., 2001:633; Armstrong & Munoz, 2003:451; Munoz et al., 2003:510; Borsting et al., 2005:588; Hanisch et al., 2005:671; Mason et al., 2005:1345; Loe et al., 2009:432). A few studies were carried out to analyse the links between ADHD and ocular motor control with regard to matters like visual attention, visual perception and ocular motor control like eye movement outside the normal fixation point, but no studies have been reported on the status of the ocular motor control of South African populations, and the effect of visual–motor intervention on the ocular motor control or visual–motor integration of learners with ADHD. The aim of the study was twofold, namely firstly to determine the ocular motor control functions and status of visual–motor integration of a selected group of 6– tot 8–year–old learners with ADHD in Brakpan, South Africa, while the second aim was to determine whether a visualmotor– based intervention programme can improve the ocular motor control and status of the visual–motor integration of a selected group of 6– to 8–year–old learners with ADHD in Brakpan, South Africa. Statistica for Windows 2010 was used to analyse the data. The Sensory Input Screening measuring instrument and the Quick Neurological Screening Test II (QNST–II) were used to assess the ocular motor control functions (fixation, ocular alignment, visual tracking and convergence–divergence), while the Beery Developmental Test of Visual–Motor Integration (VMI–4de weergawe) was used to determine the status of the learners’ visual–motor integration (VMI), visual perception (VP) and motor coordination (MC). The Disruptive Behaviour Scale, a checklist for ADHD (Bester, 2006), was used as measuring instrument to identify the learners with ADHD. Fifty–six learners (31 boys, 25 girls, with an average age of 7,03 years +0,65) participated in the pre–test and were divided into an ADHD (n=39) and a non–ADHD (n=16) group for aim one. Two–way tables were used to determine the percentage of ocular motor control deficits in the learners with and without ADHD, and an independent t–test was used to analyse the visual–motor integration of these learners. The Pearson Chi–squared test was used to determine the practical significance of differences in VMI and VP (d>0,05). The results of the study reveal that the majority of learners displayed ocular motor control deficits, regardless of whether they were classified with ADHD or not. The biggest percentage of learners fell into Class 2 (moderate deficits), particularly with regard to horizontal (68,57%; 52,63%; w=0,16) and vertical tracking (65,71%; 73,68%), as well as convergence–divergence (80%; 78,95%; w=0,11). However, it appears that ADHD learners experience more serious problems (Class 3) with visual tracking than learners without ADHD (both eyes: 22,86%; compared to 10,53% (w=0,22); right eye: 11,43% compared to 0% (p=0,05; w=0,34); left eye: 14,29% compared to 0% (p=0,02; w=0,38)). Learners with and without ADHD displayed a practically significant difference with respect to visual perception (d=0,37) and motor coordination (d=0,5) compared to learners without ADHD (who achieved better results). For aim 2 the subjects were divided into three groups. A pre–test–post–test design compiled from an availability sample of three groups (intervention group with ADHD (n=20); control group with ADHD (n=10) and control group without ADHD (n=17)) was used for this part of the study. The intervention group participated in a nine–week (3x/week and for 45 minutes) visualmotor– based intervention programme in which the ocular motor control functions section was applied for about 5 minutes per learner. Forty–seven learners (25 boys and 22 girls) with an average age of 6,95 years (+0,69) constituted the experimental group, while a control group with ADHD with an average age of 7,2 years (+0,79) and a control group without ADHD with an average age of 7,12 years (+0,60) did not receive any intervention and just participated in the pre– and post–test opportunity. A two–way cross–tabulation table was used to determine the changes in ocular motor control functions. These results mainly revealed that practically significant changes occurred in all three groups, be it improvement or deterioration in the various classes of ocular motor control. It appears that as far as horizontal and vertical visual tracking is concerned, and with convergence–divergence, more subjects were moved back from Class 3 (serious cases) to Class 1 (no deficits) and 2 (moderate deficits) in particular than in the other two groups that had received no intervention. Independent t–testing was used to analyse intragroup differences in the visual–motor integration subdivisions, while a covariance analysis (ANCOVA) (corrected for pre–test differences) was used to determine adjusted average post–test difference values. These results revealed that the motor coordination of the intervention group improved more than that of the control group with ADHD (p=0,18). This can lead to the conclusion that the intervention programme did have an effect on this specific skill. Abstract The overall indications of the results are that learners with ADHD have a general tendency to achieve poorer results in ocular motor control tests and with skills involving visual–motor integration, visual perception and motor coordination than learners without ADHD. Although only a minor improvement was identified in the experimental group after participation in the intervention programme, it is recommended with regard to motor coordination in particular that a similar programme be compiled for ADHD learners that focuses more specifically on the ocular motor control needs of each learner, and that it be presented on a more individual basis in order to accomplish greater improvement.
- ETD@PUK