Soft neurological signs and EEG pattern in rural malnourished children

Neuropsychology and Electroencephalography in Rural Children at Neurodevelopmental Risk: A Scoping Review

Children from rural areas face numerous possibilities of neurodevelopmental conditions that may compromise their well-being and optimal development. Neuropsychology and electroencephalography (EEG) have shown strong agreement in detecting correlations between these two variables and suggest an association with specific environmental and social risk factors. The present scoping review aims to describe studies reporting associations between EEG features and cognitive impairment in children from rural or vulnerable environments and describe the main risk factors influencing EEG abnormalities in these children. The method for this purpose was based on a string-based review from PubMed, EBSCOhost, and Web of Science, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Qualitative and quantitative analyses were conducted from the outcomes that complied with the selected criteria. In total, 2280 records were identified; however, only 26 were eligible: 15 for qualitative and 11 for quantitative analysis. The findings highlight the significant literature on EEG and its relationship with cognitive impairment from studies in children with epilepsy and malnutrition. In general, there is evidence for the advantages of implementing EEG diagnosis and research techniques in children living under risk conditions. Specific associations between particular EEG features and cognitive impairment are described in the reviewed literature in children. Further research is needed to better describe and integrate the state of the art regarding EEG feature extraction.

Physiological slowing and upregulation of inhibition in cortex are correlated with behavioral deficits in protein malnourished rats

Protein malnutrition during early development has been correlated with cognitive and learning disabilities in children, but the neuronal deficits caused by long-term protein deficiency are not well understood. We exposed rats from gestation up to adulthood to a protein-deficient (PD) diet, to emulate chronic protein malnutrition in humans. The offspring exhibited significantly impaired performance on the 'Gap-crossing' (GC) task after reaching maturity, a behavior that has been shown to depend on normal functioning of the somatosensory cortex. The physiological state of the somatosensory cortex was examined to determine neuronal correlates of the deficits in behavior. Extracellular multi-unit recording from layer 4 (L4) neurons that receive direct thalamocortical inputs and layers 2/3 (L2/3) neurons that are dominated by intracortical connections in the whisker-barrel cortex of PD rats exhibited significantly low spontaneous activity and depressed responses to whisker stimulation. L4 neurons were more severely affected than L2/3 neurons. The response onset was significantly delayed in L4 cells. The peak response latency of L4 and L2/3 neurons was delayed significantly. In L2/3 and L4 of the barrel cortex there was a substantial increase in GAD65 (112% over controls) and much smaller increase in NMDAR1 (12-20%), suggesting enhanced inhibition in the PD cortex. These results show that chronic protein deficiency negatively affects both thalamo-cortical and cortico-cortical transmission during somatosensory information processing. The findings support the interpretation that sustained protein deficiency interferes with features of cortical sensory processing that are likely to underlie the cognitive impairments reported in humans who have suffered from prolonged protein deficiency.

Early childhood stunting and later fine motor abilities

AIM

The aim of this study was to determine the effects of early childhood stunting (height for age 2SD or more below reference values) and interventions on fine motor abilities at 11 to 12 years, and the relationship between fine motor abilities and school achievement and intelligence.

METHOD

A cohort of stunted children who had participated in a randomized trial of psychosocial stimulation and/or nutritional supplementation in early childhood was compared with a group of non-stunted children. Fine motor abilities were assessed in 116 stunted (67 males, 49 females) and 80 non-stunted children (43 males, 37 females) at a mean age of 11 years 8 months (SD 4.3 mo) and 11 years 9 months (SD 3.8 mo) respectively. Testers were blind to the children's group assignment.

RESULTS

Two fine motor factors were derived: rapid sequential continuous movements (RSCM) and dexterity. No effect of the early intervention was found. RSCM scores were lower in the stunted group than in the non-stunted group (p=0.01), but differences in dexterity were not significant (p=0.18) after adjusting for social background. Among stunted children, the RSCM score was significantly associated with IQ (p=0.04) and school achievement (all p<0.05).

INTERPRETATION

Stunting in early childhood is associated with poor scores on tests of rapid sequential continuous hand movements in later childhood. Children with poorer scores are at greater risk for low IQs and low levels of school achievement.

Effects of prenatal protein malnutrition on the electrical cerebral activity during development

Early protein restriction during the prenatal period has significant repercussions on the ontogeny and development of the central nervous system. The present study investigates whether early prenatal protein malnutrition could alter the electrical cerebral activity of the progeny. We used Sprague-Dawley female rats of 200 g randomly divided into three groups: a control group that received a diet with 25% of the protein content (lactalbumin), the experimental group, that received a diet with 6% of the protein content and the rehabilitated group that initially received a diet with 6% of the protein content, then switched to a diet with 25% of the protein content after the weaning period (P20D) up to 60 days of life (P60D). Reduction of the protein content from 25% to 6% of lactalbumin in the diet of pregnant rats produces impairment in the electrical cerebral activity in the progeny at P20D and at P60D. The power spectral analysis for each one of the electroencephalograms revealed that prenatal protein malnutrition in rats produced a significant reduction of the alpha (8-13 Hz) and the beta bands (13-30 Hz) and a significant increase of the theta (4-8 Hz), and delta bands (1-4 Hz), at two different stages of life (P20D and P60D). Similar results were obtained for the rehabilitated group. These results indicate that early malnutrition in life affects the ontogeny of the electrical cerebral activity. This insult probably disrupts the establishment of cortical neural circuits during the critical period of brain development. The rehabilitation period did not revert the impairment in the electrical cerebral activity produced by malnutrition. We used one-way ANOVA analysis, followed by Tukey test (*p<0.001).

Motor co-ordination in a South Indian population of children

AIMS

To examine the associations of motor co-ordination in Kerala, South India.

METHODS

The Modified Oseretsky Test of motor co-ordination was administered to 1155 representative children during a door-to-door survey of 8-12 year olds. Reading, vocabulary and visuospatial reasoning were measured, as were height and weight. Information on medical history, socio-demographic background and behaviour was systematically collected.

RESULTS

Age was the major association of motor incoordination indicating the importance of maturation. Behaviour, vocabulary, visuospatial reasoning, material deprivation, perinatal complications, chronic physical symptoms and occupational status of the father were also independently associated with motor co-ordination. Using sibling pairs, evidence of familial aggregation of motor co-ordination was found.

The importance of boron nutrition for brain and psychological function

Boron (B) nutriture has been related to bone, mineral and lipid metabolism, energy utilization, and immune function. As evidence accumulates that B is essential for humans, it is important to consider possible relationships between B nutriture and brain and psychological function. Five studies conducted in our laboratory are reviewed. Assessments of brain electrical activity in both animals and humans found that B deprivation results in decreased brain electrical activity similar to that observed in nonspecific malnutrition. Assessments of cognitive and psychomotor function in humans found that B deprivation results in poorer performance on tasks of motor speed and dexterity, attention, and short-term memory. However, little support was found for anecdotal reports that supplementation with physiologic amounts of B helps alleviate the somatic and psychological symptoms of menopause. Parallels between nutritional and toxicological effects of B on brain and psychological function are presented, and possible biological mechanisms for dietary effects are reviewed. Findings support the hypothesis that B nutriture is important for brain and psychological function in humans.

Impact of chronic undernutrition on higher mental functions in Indian boys aged 10-12 years

Undernourished rural children 10-12 years of age demonstrated the following, when compared to normal nourished children: (i) a relative deficit of memory quotients assessed by the Wechsler memory scale; (ii) lower scores for abilities related to personal and current information, orientation, mental control, logical memory, digit span, visual reproduction and associative learning; (iii) impaired set formation and flexibility in attention as assessed by the card sorting test; and (iv) impairment in conditional learning on maze and conditional associative learning tests. The performance on the finger dexterity test for fine motor coordination was not affected in undernourished children.

Muscular sufficiency, serum protein, enzymes and bioenergetic studies (31-phosphorus magnetic resonance spectroscopy) in chronic malnutrition

Muscle sufficiency was significantly lower in 1336 children with chronic malnutrition of moderate to severe degree. Eighteen children with a chronic moderate degree of malnutrition and 8 well-nourished, age-matched controls were selected for biochemical and 31-phosphorus magnetic resonance spectroscopy (31-P MRS) studies. The results showed that: (a) serum total protein, albumin, iron, calcium and inorganic phosphate were similar in both groups; (b) serum enzyme levels were significantly increased in the malnourished group; (c) 31-P MRS showed significantly higher means for total ATP, beta-ATP, alpha-ATP and inorganic phosphate for the malnourished compared to the control group. In chronic malnutrition, proteins are maintained by degradation in muscle resulting in release of amino acids and enzymes. 31-P MRS studies showing increases in total ATP, beta-ATP and inorganic phosphate and a decrease in phosphocreatine suggest that ATP is maintained at the cost of phosphocreatine.

Early child health in Lahore, Pakistan: XII. Milestones

Psychomotor development was assessed in 1476 infants from four different levels of urbanization in and around Lahore, Pakistan. Development was assessed monthly at birth to 24 months of age by using a set of 10 milestones selected from the Denver Developmental Screening Test and the Developmental Screening Inventory. The psychomotor development of children in the upper middle (Um) class was consistent with reference population groups in Europe and North America, hence this group was used as control. There was significant delay in the psychomotor development of infants belonging to the poorer areas compared to the Um class. There was no sex difference in the development of the milestones in any study area, except for girls in the Um class who were earlier for about one month than boys in talking. Infants in the poorer areas were, on average about 3 months, delayed in their walking and fine motor activity (building a tower of 3 cubes) in comparison with the Um class. Observed disturbance in psychomotor development at an early age may affect the abilities and achievements in later life.

Partial imitation and partial sensory agnosia in mentally normal children with convulsive disorders

Mentally normal 6-9 year old children with or without convulsive disorders were examined using the procedures of the five soft signs (SS) selected from conventional soft neurological signs and Bergès' gesture imitation tasks. In comparisons of SS between the 60 children with convulsive disorders (CD group) and the 38 without (N group), the average number of SS detected in each case and the incidence ratio of the two signs--partial imitation (PI) and partial sensory agnosia (PSA)--were higher in the CD group than the N group. Examinations of relationships between age, IQ, error index (EI; an index taken from the Continuous Performance Test) and SS, and of correlations among the SS, found two kinds of SS: age-related and El-related signs. The former included right-left confusion, clumsiness and PI, which correlated with each other, while the latter included unstableness of lateral gazing and PSA, which did not correlate with each other. Even though several factors belonging to characteristics of convulsive disorders were evaluated concerning the presence or absence of PI and PSA, there was only one relationship: PSA was more common in children with febrile convulsions than in those with epilepsy. We speculated that PSA reflected an immaturity of the brain in children with febrile convulsions.