THE EVOLUTION OF INFANTILE POSTURAL REFLEXES IN THE PRESENCE OF CHRONIC BRAIN SYNDROMES

Primary reflex persistence in children with reading difficulties (dyslexia): A cross-sectional study

The primary reflex system emerges during fetal life and is inhibited during the first year after birth. Our aim was to examine the effects of persistence of this early neurological system on the attainment of core literacy skills in dyslexic and non-dyslexic poor readers. We assessed the prevalence of a persistent primary reflex in a cross-sectional, representative sample of children (n=739) aged 7-9 years old attending mainstream primary school in Northern Ireland using standardised educational tests, and a clinical diagnostic test for a primary reflex (the asymmetrical tonic neck reflex (ATNR)). Multiple regression analyses, involving all of the sample children, revealed that persistence of the ATNR was significantly predictive of attainments in reading (t=-8.34, p<.001), spelling (t=-8.00, p<.001), non-word reading (t=-16.15, p<.001), and verbal IQ (t=-4.71, p<.001). ANOVA tests revealed that there were no differences between the performance of dyslexic and non-dyslexic poor readers on any of the outcome measures (reading (F(1, 289)=0.51, p=.48), spelling (F(1, 289)=0.02, p=.90), non-word reading (F(1, 289)=0.76, p=.38), ATNR level (F(1, 289)=2.54, p=.11)). Further ANOVA tests revealed that males had significantly higher levels of persistent reflex than females (F(1, 737)=15.21, p<.001), and that children from socially disadvantaged backgrounds had significantly higher levels of reflex than children who were not socially disadvantaged (F(1, 737)=20.84, p<.001). The findings suggest that for many children in mainstream schooling, the attainment of core educational skills may be affected by the persistence of a brainstem mediated reflex system that should have been inhibited in the first year after birth. Furthermore, these findings suggest that dyslexia is not a distinct category of poor reading, and that it may be more valid to term all poor readers as dyslexic irrespective of IQ.

Prevalence of persistent primary reflexes and motor problems in children with reading difficulties

It has been shown that some children with reading difficulties have underlying developmental delay and that this may be related to the persistence of primary reflexes. This study investigated the prevalence of persistent primary reflexes in the ordinary primary school population and how this related to other cognitive and social factors. Three groups of 41 children were drawn from a representative, cross-sectional sample of 409 children (aged 9-10 years) attending 11 ordinary primary schools in N. Ireland. The three groups represented the bottom, middle and top 10% respectively of readers from the total sample population. The relative persistence (on a scale of 0 to 4) of the Asymmetrical Tonic Neck Reflex (ATNR) and the prevalence of motor difficulties were assessed for these 3 groups. The rôle of 5 predictor variables (verbal IQ, social deprivation, sex, month of birth and religious affiliation) in determining the reading level of the total sample was also investigated. It was found that the lowest reading group had a significantly higher mean level of ATNR (1.56 [95% CI 1.22-1.90]) compared with the middle reading group (0.56 [0.22-0.90]) and the top reading group (0.59 [0.25-0.92]). 17% of children in the lowest reading group had extremely high levels of the ATNR while 24% showed no presence of ATNR. This contrasted with 0% and 66%, respectively for both middle and top reading groups. It was also found that there was a significant difference between the lowest reading group and the top reading group on a standardised test of motor ability. Furthermore, there was evidence that ATNR persistence but not motor ability was associated with the sex of the child with boys, in particular, at risk. There was no evidence that ATNR persistence or motor ability was significantly associated with social deprivation. It was also found that there were no significant differences between dyslexic and non-dyslexic children with reading difficulties in motor (including balance) performance. This study highlights the high levels of primary reflex persistence in children with reading difficulties and it provides further evidence of the association between reading difficulties and movement difficulties in young children. However, while the implications for intervention are discussed, it is stressed that the persistence of primary reflexes cannot be used as a causal model for reading difficulties, including dyslexia.

Primitive reflexes and postural reactions in the neurodevelopmental examination

The primitive reflexes and the postural reactions comprise one of the earliest, simplest, and most frequently used tools among child neurologists to assess the central nervous system integrity of infants and young children. Infants with cerebral palsy have been known to manifest persistence or delay in the disappearance of primitive reflexes and pathologic or absent postural reactions. The clinical significance of asymmetric tonic neck reflex, Moro, palmar grasp, plantar grasp, Galant, Babinski, Rossolimo, crossed extensor, suprapubic extensor, and heel reflex, alone or in combination, as well as their contribution to the early diagnosis and differential diagnosis of cerebral palsy, have been demonstrated in a number of studies. Moreover, infants with 5 or more abnormal postural reactions have developed either cerebral palsy or developmental retardation as reported in a number of studies. Although a comprehensive neurologic examination in the context of a motor assessment instrument is preferable to an informal list of items, the combined examination of primitive reflexes and postural reactions should be considered by the child neurologist, as a simple but predictive screening test for the early identification of infants at risk for cerebral palsy. It is quick and easy to perform, both in nonhospital environments and in underdeveloped countries, where time and specific recourses are limited. The combined examination is also useful in developed countries because many developmental disorders such as cerebral palsy appear in nonrisk groups whereas others are not detected by metabolic screening programs.

Effects of replicating primary-reflex movements on specific reading difficulties in children: a randomised, double-blind, controlled trial

BACKGROUND

Children with specific reading difficulties have problems that extend beyond the range of underlying language-related deficits (eg, they have difficulties with balance and motor control). We investigated the role of persistent primary reflexes (which are closely linked in the earliest months of life to the balance system) in disrupting the development of reading skills.

METHODS

We assessed the efficacy of an intervention programme based on replicating the movements generated by the primary-reflex system during fetal and neonatal life. A randomised, individually matched, double-blind, placebo-controlled design was used and children (aged 8-11 years) with persistent primary reflexes and a poor standard of reading were enrolled into one of three treatment groups: experimental (children were given a specific movement sequence); placebo-control (children were given non-specific movements); and control (no movements).

FINDINGS

From an initial sample of 98 children, 60 children, 20 in each group were matched on age, sex, verbal intelligence quotient (IQ), reading ability, and persistent asymmetrical tonic neck reflex. For asymmetrical tonic neck-reflex levels there was a significant (group by time) interaction (p<0.001). The experimental group showed a significant decrease in the level of persistent reflex over the course of the study (mean change -1.8 [95% CI -2.4 to -1.2], p<0.001), whereas the changes in the placebo-control and control groups were not significant (-0.2 [-0.9 to 0.6] and -0.4 [-0.9 to 0.2]).

INTERPRETATION

This study provides further evidence of a link between reading difficulties and control of movement in children. In particular, our study highlights how the educational functioning of children may be linked to interference from an early neurodevelopmental system (the primary-reflex system). A new approach to the treatment of children with reading difficulties is proposed involving assessment of underlying neurological functioning, and appropriate remediation.

Primitive reflexes. Their contribution to the early detection of cerebral palsy

In evaluating the infant for significant motor impairment, a framework to organize and analyze data is presented. Five general areas of information are essential: (1) motor milestone attainment, (2) the classic neurological examination, (3) primitive reflex and postural reaction patterns, (4) progressive vs static nature of the dysfunction, and (5) associated evidence for neurological dysfunction and/or structural nervous system damage. A sixth criterion, age of onset, is relevant--but controversial--to making the specific diagnosis of cerebral palsy. The treatment of and prognosis for children with cerebral palsy have been linked to the historical and examination features outlined, particularly primitive reflexes. For the practicing pediatrician, understanding the fundamentals of the primitive reflex/postural reaction transition and achieving clinical facility with the elicitation of these signs represent skills that are readily acquired, easy to incorporate in routine clinical practice, and diagnostically useful.

Athetoid cerebral palsy with cysts in the putamen after hypoxic-ischaemic encephalopathy

Three cases of athetoid cerebral palsy after hypoxic-ischaemic encephalopathy (HIE) are reported. All three neonates had haemorrhagic lesions in the basal ganglia and thalami on magnetic resonance imaging (MRI). Prior cranial ultrasound had detected the lesions in only two cases. In all three children athetoid movements began within the first year of life. Follow up MRI scans showed bilateral symmetrical cystic lesions in the posterior putamen. Although haemorrhagic lesions within the basal ganglia are a common MRI finding in neonates with HIE, few of these babies develop athetoid cerebral palsy. We believe this to be the first report of discrete cystic lesions found in the basal ganglia of children with athetoid cerebral palsy.

[Factors involved in the prognosis of walking in cerebral paralysis]

With the objective of studying the prognosis for walking in children with cerebral palsy a retrospective survey of 100 children being treated at the Associação de Assistência à Criança Defeituosa was made during the period from 1979 to 1988. The following parameters were analysed: (1) degree of motor dysfunction; (2) age of acquisition of sitting balance; (3) function of upper limbs; (4) degree of mental retardation; (5) presence of primitive reflexes. All the above parameters were analysed with respect to the capability of children acquiring or not walking. The results of our study show that the following factors are indicative of bad prognosis for walking: (1) severity of motor dysfunction; (2) acquisition of sitting posture after 3 years old; (3) precarius function of upper limbs; (4) severe mental retardation associated with severe physical deficiency. Clinical evaluation of primitive reflexes did not reveal direct relation to the walking prognosis.

Residual developmental disabilities in children with transient hypertonicity in infancy

Developmental disabilities occurred in children who manifested transient neurologic abnormalities in early infancy. In an attempt to identify associated problems at an earlier age, the neuromotor and developmental progress of 33 children who had transient hypertonicity during early infancy was analyzed. At 2-3 years of age, various developmental abnormalities were identified in more than two-thirds of these children. Delays in speech and language development and also in fine motor/adaptive and behavioral difficulties were most frequently present. Over time, these problems persisted and other disorders also became apparent. At 5 years of age or older, learning disabilities were frequent and associated with language and perceptual problems. None of the patients had epilepsy; mental retardation was present in only 2 children. Our study demonstrates that children with transient hypertonicity in early infancy are at risk for various developmental problems which can be identified as early as 2 years of age. It also indicates that although their severity lessens over time, these developmental abnormalities tend to persist.

The Bobath Approach and its Application in Occupational Therapy for Children with Cerebral Palsy

Each paediatric occupational therapist brings to the field his or her life and clinical experiences and theoretical frameworks. Since completing the Bobath course in London in 1981, the author's approach to the assessment and management of children with movement problems is based on the neurodevelopmental approach (and, if appropriate, the sensory and perceptual motor and behavioural approaches). This article outlines the Bobath approach and its application in occupational therapy for children with cerebral palsy, and finally reviews the approach based on the author's experience and from selected literature.

Hip dislocation in cerebral palsy: selection for treatment

Forty-five patients with cerebral palsy hip-dislocation were reviewed and it was found that some did well without treatment. For patients with hip pain, the best results were obtained with extensive resection arthroplasty: soft-tissue surgery alone was unsuccessful. Open reduction with femoral osteotomy achieved concentric reduction in all 15 patients who had this type of surgery: however, most retained their abnormal postural reflex activity to such a degree that subsequent scoliosis, pelvic obliquity, hip extension contractures and knee flexion deformities compromised the success of the hip surgery.

Motor functions: associated primitive reflex profiles

The results of reflex/motor activity interactions in 177 normal infants are evaluated. The asymmetrical tonic neck reflex, tonic labyrinthine reflex-supine, and Moro reflexes were assessed for each child at birth and at intervals up to 12 months. Ages of rolling prone to supine, rolling supine to prone, and sitting alone were elicited from parents. The effects of the primitive reflexes on early motor activity were assessed, and statistically significant correlations were demonstrated between decreased reflex activity and the emergence of motor milestones. The distinctive association of reflex activity with motor function suggests the interaction of several reflexes (a primitive reflex profile) rather than the influence of isolated reflex activity. Such patterns support the hypothesis that decreasing primitive reflex activity is associated with the onset of volitional motor activity in normal infants.

Delayed-onset dystonia in patients with "static" encephalopathy

Eight cases of persistent dystonia appearing one to 14 years after non-progressive cerebral insults are described. Five were due to perinatal anoxia, one to trauma, and two to cerebral infarction. This phenomemon of delayed-onset dystonia has not been described previously, although review of earlier literature reveals several probable examples. Delayed-onset dystonia due to perinatal anoxia is an important diagnostic alternative to dystonia musculorum deformans for dystonia occurring in childhood.

Clinical and experimental studies of phenytoin-induced hyperkinesias

Phenytoin administration occasionally leads to the induction of hyperkinetic movement disorders. The pathophysiologic basis of this phenomena is unknown, but thought to be a toxic effect of phenytoin. Study of two cases of this disorder and a review of the literature suggest that antecedant pathologic changes in the basal ganglia are prerequisites for the development of phenytoin-induced hyperkinesias. In an animal model of tardive dyskinesia, phenytoin was found to enhance neuroleptic-induced behavioral supersensitivity but have no effect in control animals. We conclude that phenytoin induced hyperkinesias reflect a specific effect of phenytoin on an abnormal neural substrate and suggest the presence of an otherwise silent pathological alteration of the corpus striatum. The diagnostic value of an episode of phenytoin-induced hyperkinesia is discussed.