Summary of Paper presented at THE 5TH BDA INTERNATIONAL CONFERENCE. DYLSEXIA: AT THE DAWN OF THE CENTURY. University of York 18th-21st April 2001
A study of 54 children who had received an independent diagnosis of Dyslexia revealed that they all showed evidence of immature motor skills and related difficulties on a range of standardised neurological tests. These findings suggest that physical factors do play a significant role in some children diagnosed with Dyslexia.
It is an accepted medical fact that primitive reflexes should not persist above 6 months of age (12 months at the latest), and that postural reflexes should be fully developed by three-and-a- half years of age. Abnormalities in an individual's profile of primitive and postural reflexes at a later age provide reliable diagnostic signposts of central nervous system immaturity.
A sample of 54 children aged 8 - 15 years who had previously received a diagnosis of Dyslexia were examined for the presence of primitive and postural reflexes. An historical control was assumed on the basis of the accepted medical premise that primitive reflexes should not be present above 6 months of age and that postural reflexes should be developed by three and a half years of age. Additional tests were carried out to assess oculo motor functioning (control of eye movements), visual-perceptual performance, cerebellar involvement and dysdiadochokinesia (difficulty with rapid alternate movements).
Abnormal primitive and postural reflexes were found to be a significant underlying factor in this sample. The Asymmetrical Tonic Neck (ATNR) and Tonic Labyrinthine (TLR) reflexes were present in 100% of the sample. Both of these reflexes have a direct affect upon the functioning of the vestibular system (balance mechanism) and its connections to the centres which control eye movements. Other reflexes found to be significant were: The Symmetrical Tonic Neck Reflex, the Spinal Galant reflex, Palmar, Plantar and Rooting reflexes. Postural reflexes were also found to be under-developed.
*53% showed some signs of cerebellar involvement and 85% had difficulty with at least one of the tests for dysdiadochokinesia indicating poorly developed bilateral integration.
*92% of the sample demonstrated difficulties with oculo-motor skills, of which:
*83% had difficulty with visual tracking;
*59% had difficulty with near-point convergence (necessary to fuse the two separate images seen by each eye to send a single unified image to the brain);
*42% had difficulty with visual discrimination;
*77% showed evidence of stimulus bound effect
*98% had difficulty with hand-eye co-ordination
The results suggest that whilst individual reflex abnormalities impair functioning in specific skills, the combined effect of a cluster of abnormal reflexes can have an impact upon learning in general, particularly those areas of learning which require co-operation with the motor system. Reading may be affected because it requires a level of oculo-motor functioning. Writing is a motor task that depends upon co-ordination of the hands and the eyes with automatic support from the postural system. Lack of automisation in the acquisition of motor related skills can then affect performance on written language and other motor dependent skills.
Two recent studies have demonstrated improvements in reading (McPhillips, Hepper and Mulhern 2000) and in eye movements (Bein-Wierzbinski 2001) as a result of specific reflex stimulation and inhibition movements. The results of this study suggest that examination of patterns of motor development, oculo-motor functioning and visual-perceptual performance should be more widely used as part of the assessment procedure of a child suspected of having Dyslexia ,so that appropriate intervention at a physical level can be included in addition to specialist teaching.
Bein-Wierzbinski W 2001 Persistent primitive reflexes in elementary school children. Paper presented at The 13th European Conference of Neuro-Developmental Delay in Children with Specific Learning Difficulties. Chester. March 2001
McPhillips M, Hepper PG, Mulhern G 2000 Effects of replicating primary reflex movements on specific reading difficulties in children. Lancet 355
Full transcript of the paper available on CD from The British Dyslexia Association. Proceedings of the 5th BDA International Conference or from the corresponding author:
Sally Goddard Blythe
The Institute for Neuro-Physiological Psychology (INPP)
4, Stanley Place
Chester CH 2LU