Head size and intelligence, learning, nutritional status and brain development

Abstract

This multifactorial study investigates the interrelationships between head circumference (HC) and intellectual quotient (IQ), learning, nutritional status and brain development in Chilean school-age children graduating from high school, of both sexes and with high and low IQ and socio-economic strata (SES). The sample consisted of 96 right-handed healthy students (mean age 18.0 +/- 0.9 years) born at term. HC was measured both in the children and their parents and was expressed as Z-score (Z-HC). In children, IQ was determined by means of the Wechsler Intelligence Scale for Adults-Revised (WAIS-R), scholastic achievement (SA) through the standard Spanish language and mathematics tests and the academic aptitude test (AAT) score, nutritional status was assessed through anthropometric indicators, brain development was determined by magnetic resonance imaging (MRI) and SES applying the Graffar modified method. Results showed that microcephalic children (Z-HC < or = 2 S.D.) had significantly lower values mainly for brain volume (BV), parental Z-HC, IQ, SA, AAT, birth length (BL) and a significantly higher incidence of undernutrition in the first year of life compared with their macrocephalic peers (Z-HC > 2S.D.). Multiple regression analysis revealed that BV, parental Z-HC and BL were the independent variables with the greatest explanatory power for child's Z-HC variance (r(2) = 0.727). These findings confirm the hypothesis formulated in this study: (1) independently of age, sex and SES, brain parameters, parental HC and prenatal nutritional indicators are the most important independent variables that determine HC and (2) microcephalic children present multiple disorders not only related to BV but also to IQ, SA and nutritional background.

Lack of severe long-term outcomes of acute, subclinical B1 deficiency in 216 children in Israel exposed in early infancy

“…The long-term neurobehavioral development of young children is largely dependent on the environment they are exposed to (12)(13)(14). Intrauterine exposure of the fetus to neuroteratogenic agents such as heroin, cocaine, and alcohol may have deleterious effects on long-term postnatal development (15,16).…”

“…Intrauterine exposure of the fetus to neuroteratogenic agents such as heroin, cocaine, and alcohol may have deleterious effects on long-term postnatal development (15,16). Postnatal exposure of normal infants to a damaging environment, including nutritional deficiencies especially during the first year of life, may have long-lasting effects similar to those observed following intrauterine exposure (12,(17)(18)(19). Indeed, such long-term developmental consequences have been associated with deficiencies in several vitamins in childhood, including vitamin B 12 (20).…”

“…Postnatal exposure of normal infants to a damaging environment, including nutritional deficiencies especially during the first year of life, may have long-lasting effects similar to those observed following intrauterine exposure (12,(17)(18)(19). Indeed, such long-term developmental consequences have been associated with deficiencies in several vitamins in childhood, including vitamin B 12 (20). It is not clear whether mild or subclinical B 1 deficiency in infancy, which theoretically could cause slight Articles Ornoy et al…”

Cognitive decline is associated with nutritional risk in subjects with small head circumference (HC)

“…HC is also the most sensitive anthropometric indicator of prolonged malnutrition during infancy and can be associated with intellectual impairment (Ivanovic et al, 2000(Ivanovic et al, , 2002. Malnutrition alters brain development and intelligence in a multi-causal context, and poverty and deprivation exacerbate these negative effects, especially when these factors persist throughout a lifetime (Ivanovic et al, 2004). Under these conditions, a stable environment that provides adequate stimulation is very difficult to achieve, and for this reason the brain damage caused by malnutrition at an early age frequently is not reversible (Brown and Pollitt, 1996).…”

Parental IQ and cognitive development of malnourished Indonesian children

“…Elucidating the effect of malnutrition on cognitive development has remained difficult, due to covarying risk factors and the inability to perform randomized controlled studies (Grantham-McGregor, 1995). A number of studies have shown a small long-term negative effect of malnutrition on IQ after adjusting for socioeconomic factors and education (Freeman et al, 1980;Galler et al, 1983Galler et al, , 1990Rose, 1994;Mendez & Adair, 1999;Ivanovic et al, 2000Ivanovic et al, , 2004Berkman et al, 2002;Jianghong et al, 2003). However, these studies have not controlled for parental IQ.…”