H. Naudé

Can Cultural Behavior have a Negative Impact on the Development of Visual Integration Pathways

Optimal cognitive development and maturity depends on optimal auditory, visual and tactile-kinesthetic perception. It is therefore important that an infant should be actively involved and participate physically in the mastery of concrete objects during Piagets sensorimotor stage. We postulate that cultural behavior such as Pêpa (carrying the baby on the mothers back) can have a negative impact on the development of visual integration pathways, as it prevents the child to crawl adequately or enough during the sensorimotor stage. We believe that crawling is essential for cross-modality integration and that higher mental functions may suffer as a result of the interruption of the links that are part of the structure of a complex functional system. We therefore suggest that the prolonged Pêpa activity may have detrimental effects on the development of the visual integration pathways. These pathways develop during the sensorimotor developmental stage. Since the effect of Pêpa will only become evident during a school readiness screening or scholastic performance assessment, useful tests and practical assessment devices are proposed that school psychologists could use.

The Contribution of Prenatal Stress to the Pathogenesis of Autism as a Neurobiological Developmental Disorder: A Dizygotic Twin Study.

This paper reports on the contribution of prenatal stress to the pathogenesis of autism as a neurobiological developmental disorder in a dizygotic study. The aim was to explore whether the neurobiological impact of stress prior to week 28 of gestation might be related to the pathogenesis of autism. The following data‐generating strategies were employed: a diagnostic stress inventory, the 16‐Personality Factor Questionnaire, magnetic resonance imaging and blood plasma sampling. It was found that maternal stress during pregnancy may have produced elevated leucocytes and glucocorticoids during gestation, because stress affects cellular immunity due to involvement of the hipothalamic–pituary–adrenal axis. These were implicated in suboptimal placental functioning, heightened exposure of the foetus to glucocorticoids and altered neural development. The autistic subject’s blood plasma pathology results showed elevated glucocorticoids and serotonin. Significant cortisol and serotonin differences were noted in the blood plasma pathology results of the autistic subject and the control. Hyperserotonemia and elevated glucocorticoids were therefore implicated in altered programmed neural development, as suggested by the autistic subject’s magnetic resonance images. Differences in head circumference were also noted. It was concluded that prenatal maternal stress might have significantly contributed to the pathogenesis of autism.

Cognitive and learning strategies for longstanding temporal lobe lesions in a child who suffered from Herpes simplex virus encephalitis: a case study over 10 years

This article presents a case study indicating that Herpes simplex virus (HSV) encephalitis may cause permanent learning disabilities due to damage to the temporal lobes as it discusses the results of a case study extending over 10 years to determine the long‐term effects on both the anatomy of the brain and the intellectual functioning of the subject. Magnetic resonance imaging (MRI) scans were taken of the subject during the initial HSV encephalitis infection and subsequently six months after recovery. Follow‐up MRI scans were taken 10 years later. At this time the Senior South African Individual Scale—Revised IQ test was administered to determine any residual neuropsychological impairment due to HSV encephalitis infection. Follow‐up MRI analysis indicated permanent bilateral necrotic areas in the medial temporal lobe, while the IQ test revealed marked impairment of the short‐term memory, verbal memory, visual memory, visual scanning abilities and gestalt formation, which can be ascribed to temporal lobe lesions.

Executive emotional system disruption as causal agent in frontal lobishness among abused children

This article aims to explore Executive Emotional System (EES) disruption as causal agent in frontal lobishness among abused children. The Revised Senior South African Individual Scale (SSAIS‐R) was used to assess a sample population of seventy‐five male and female subjects between the ages of 8 years 0 months and 16 years 11 months who were exposed to child abuse to such levels that warranted admission to a Place of Safety. The data was computerized and frequencies projected as proportions and percentages. A one‐way analysis of variance parametric technique was implemented and p values calculated to verify significant tendencies. The results proved compromised memory and verbal processing abilities (p = 0.0001), with a reduction of global intellectual functioning among all subjects (p = 0.0001). Although frontal lobishness is usually associated with neurological insult, the authors argue that abused subjects displayed very similar manifestations. In addition to acknowledged symptoms, abused subjects presented with symptoms such as depressed explicit–declarative memory (especially the semantic memory), as well as poor error detection and restoration, despite advanced levels of social knowledge (episodic memory). The results provided support for EES disruption in frontal lobishness among abused subjects, with the interpretation that a build‐up of memory impairment accompanied by inaccessibility of existing memory deposits might account for frontal lobishness among abused children. Because these impairments cannot be purely ascribed to diagnosed frontal insult, the authors suggest that the term pseudo‐frontal lobishness be used to describe this type of executive dysfunction among abused subjects.

The Effects of Hypo- and Hypervitaminosis a and Its Involvement in Foetal Nervous System Development and Post-Natal Sensorimotor Functioning – A Review

(2006). The Effects of Hypo- and Hypervitaminosis a and Its Involvement in Foetal Nervous System Development and Post-Natal Sensorimotor Functioning – A Review. The British Journal of Development Disabilities: Vol. 52, No. 102, pp. 47-64.

Training the hippocampus and amygdala of preschool children by means of priming tasks: should parents rather focus on learning of facts than reading fairytales?

One of the main functions of the human brain is memory, and this forms the basis of learning and is the cornerstone of IQ. One of the important aims for both parents and educators of preschool children is to improve or develop the child’s self‐application of intelligence in the classroom, which indirectly involves memory capability development. The most obvious activity employed is reading. The current article investigates avenues of improving memory in preschool children and examines how memory skills and perhaps IQ levels can be improved. In this investigation the role of the hippocampus as well as the amygdale is investigated. Furthermore, two hypotheses are set: ‘reading’ of, for example, fairytales only once to a child without repeating and discussing they does not necessarily improve the memory of a child; while facts repeated or ‘replayed’ enhance ‘memory’, and ‘memory practicing’ and environmental enrichment should form an integral part of a child’s education. In order to investigate the two hypotheses discussed in this paper, a pilot study is based on a case study of a preschool boy whose IQ was tested at age five years and seven months, followed by regular memory ‘training’ and again tested at age six years. Results indicated large improvements on subtest scores resulting in a gain in functional age. We conclude, although controversially, that parents and educators should place more emphasis on memory ‘training’ activities followed by reinforcement of facts, than perhaps lengthy and sometimes taxing reading activities. Many parents and educators believe that reading should be done on a daily basis, but due to time limitations many of them struggle to create a positive reading climate conducive for learning. Priming tasks intended to stimulate those cortical structures involved in memory can be done in a much shorter time and can be successfully combined with the evening routines of the family.

Results from an Empirical Study: The impact of carrying a child on the back on the development of visual integration pathways

Optimal cognitive development and maturation depends on optimal auditory, visual and tactile-kinesthetic perception. It is therefore important that an infant should be actively involved and participate physically in the mastery of concrete objects during Piagets sensorimotor stage. In a previous study, Pretorius and coworkers postulated that cultural behavior such as Pêpa (carrying the baby on the mothers back) could have a negative impact on the development of visual integration pathways, as it prevents the child to crawl adequately or enough during the sensorimotor stage. To prove the hypothesis presented previously, we present results from an empirical study conducted in a black township in South Africa.

Can Excess Bilirubin Levels Cause Learning Difficulties

Objective. Jaundice due to excessive unconjugated bilirubin, is observed in approximately 60% of term infants during the first week of life and in approximately 80% of preterm infants. We hypothesize that excessive unconjugated bilirubin levels may result in learning difficulties because of damage to the thalamus, the hippocampus, the central areas of the cerebellum, the basal ganglia area, and in particular because of damage to the astrocytes associated with neurons of the basal ganglia area. We suggest that these infants appear to recover fully from jaundice but present with learning difficulties later when exposed to an educational environment. Methods. IQ scores of a group of children ( n =22) with learning difficulties (due to excessively high levels of unconjugated bilirubin) are also discussed. The Senior South African Individual Scale - Revised (SSAIS-R) was administered to determine the intellectual functioning of the subjects. The SSAIS-R has been standardised for South African children between the ages of 7 years 0 months and 16 years 11 months with Afrikaans or English as mother tongue. The SSAIS-R is a point scale (deviation IQ scale) and is based on research data derived from the Wechsler Intelligence Scale for Children - Revised (WISC-R). Observed verbal and non-verbal subtest scores, along with standardized total scores are summarized using descriptive statistics and Hotellings T-test and individual verbal and non-verbal subtest scores are discussed. Results. Results indicate that these children have lowered verbal abilities. The majority of subjects revealed impaired short-term and long-term memory. Based on the literature kernicterus and high levels of unconjugated bilirubin affects the basal ganglia and the formation of astrocytes, and possibly also the hippocampus, the thalamus and central parts of the cerebellum. The hippocampus has important functions in the storing of new information in forms that can be used in long-term memory. Damage to the left region of the hippocampus impairs verbal memory in all its modalities. Conclusion. Impaired formation of astrocytes associated with high levels of unconjugated bilirubin should be considered as an etiological factor in poor memory. We recommend that pediatricians should suggest early screening procedures to infants at risk. With early screening for possible deficiencies of attention, memory, and visual-motor integration functioning as well as intervention programs the learning difficulties can be addressed and remediation started earlier in life

Evidence of Early Childhood Defects Due to Prenatal Over-Exposure to Vitamin A: A Case Study.

One of the important nutrients during pregnancy is vitamin A or related compounds called retinoids. Although it is well‐known that vitamin A deficiency may be detrimental to foetal development, overdosage of retinoids might cause developmental defects, particularly affecting the central nervous system development of the foetus, causing hindbrain dysfunction which may be associated with cognitive impairment. Here we discuss a case study based on a 7 years 11 months grade one girl who was prenatally exposed to high dosages of vitamin A. The baby reached her developmental milestones later than expected, she never crawled properly, and she experienced difficulty in maintaining her balance. She suffers from lateral nystagmus and slight strabismus, resulting in diplopia, while tactile defensiveness was also reported. In the current study, the Senior South African Individual Scale – Revised (SSAIS‐R) as well as the Quick Neurological Screening Test – Revised Edition (QNST) were performed and this suggested that the hindbrain, the cerebellum and the hippocampus, including related pathways to the parieto‐temporo‐occipital region, were affected. Furthermore, sensory and motor impairment as well as inaccuracy of movements, poor timing and rhythm, compromised spatial perception, and associated somatoperceptual impairment were demonstrated. We conclude that results from the SSAIS‐R and the QNST both indicate cognitive impairment that can be linked back to hindbrain impairment and that cognitive impairment due to vitamin A overdose can be assessed using educational testing.

Piracetam: its possible mode of action in children with learning disabilities and its effect on in vitro cell growth

The use of pharmaceutical products such as Piracetam (Nootropil®) for the treatment of learning disabilities is becoming increasingly prevalent, and some studies have shown successful treatment of learning disabilities in children. This research article will discuss traditional uses of Piracetam, as well as uses in learning disabilities, with particular focus on case studies where it has been given to children with learning disabilities. Furthermore, we investigate how Piracetam could potentially enhance learning, with specific focus on brain areas. However, even though Piracetam may enhance learning, the question that arises is how safe it is at a cellular level. Therefore the effect of Piracetam at a cellular level was determined. To achieve this purpose the effect of a 24‐hour exposure to 0–70 mM Piracetam on the growth of the L929 cell line and chick embryonic neurons in vitro was investigated. No statistically significant changes in cell viability or number was observed at 0–7 mM Piracetam in both cell types, although at 70 mM cell viability in the L929 cell line was significantly reduced when compared with the control. Initial studies indicate that Piacetam is only toxic at concentrations greater than 70 mM; however, the effects of repeated dosages over long periods still need to be investigated.