Mental development

The sex chromosome abnormalities are generally less severe In terms of their effects on mental development, but two of them, the XO and XX abnormalities, are associated with sterility and other abnormalities In Individuals who develop as females or males, respectively The two other sex chromosome abnormalities, XXX and X Y, are more problematic The XXX constitution does not produce significant abnormalities In the females who have It but can. In some Individuals, be associated with a modest degree of mental slowness (45) The XYY constitution. In the males who have It, appears to be associated with Increased stature and, at least In some Individuals, with a tendency toward antisocial behavior (46, 47) While the absolute Incidence of such behavior of XYY Individuals Is probably quite low. It Is still thou t to be higher than In a chromosomally normal population These two sex-chromosome abnormalities have been specifically mentioned because they have engendered considerable concern about what types of counseling should be given In situations In which they are detected prenatally ... 

In the Oshsk Oblast (Kirgizia) in the 1960s, 65 children born to women with chronic granosan poisoning were observed to be retarded in their physical and mental development, ill, and/or unviable [A25]. 

Schroeder et al. (1985) and Schroeder and Hawk (1987) evaluated 104 black children of lower socioeconomic status at ages 10 months to 6.5 years, using the Bayley Mental Development Index (MDI) or Stanford-Binet IQ Scale. Hierarchical backward stepwise regression analyses indicated that PbB levels (range 6-59 pg/dL) were a significant source of the variance in IQ and MDI scores after controlling for socioeconomic status and other factors. Fifty of the children were examined again 5 years later, at which time PbB levels were 30 pg/dL. The 5-year follow-up IQ scores were inversely correlated with... 

Bradley JE, Baumgartner RJ. 1958. Subsequent mental development of children with lead encephalopathy, as related to type of treatment. J Pediatr 53 311-315. 

C2. Clay, P. R., and Potter, C. T., A case of galactosaemia with special reference to mental development. Arch. Disease Childhood 30, 147-149 (1955). 

Burks, B. S. (1928a). Chapter X. The relative influence of nature and nurture upon mental development A comparative study of foster parent-offspring child resemblance and true parent-true child resemblance. Yearbook of the National Society for the Study of Education, 27, 219-316. 

What are these subclinical effects Very simply, they are effects that occur at blood lead levels below those that produce clinically measurable effects - they occur in the absence of any sign of overt lead poisoning. These effects can be detected only by studying various forms of behavior, such as degree of hyperactivity and classroom attention span, and performance on various tests of intelligence and mental development. Deficits in neurobehavioral development, as measured by two widely used tests - the Bayley and McCarthy Scales - have been reported in children exposed prenatally (via maternal blood) to blood... 

Brain The usual signs and symptoms include ataxia, dementia, deafness and sometimes seizures. Not surprisingly, there is failure of mental development in children. 

Trace amounts of iodine are required for a healthy body. Iodine is part of the hormone thyroxin produced by the thyroid gland. Thyroid secretions control the physical and mental development of the human body. A goiter, a swelling of the thyroid gland, is caused by the lack of iodine. Adding thyroid medication and iodized salt to the diet helps prevent this disease. Radioactive iodine (1-131), with a half-life of eight days, is used to treat some diseases of the thyroid gland. 

Lead 0.015 mg/L Infants delay physical and mental development... 

The hallmarks of infantile hypothyroidism (e.g., retardation of mental development and growth) become manifest only in later infancy and are largely irreversible. Consequently, early recognition and initiation of replacement therapy are crucial. In the absence of thyroid hormone therapy, the symptoms of infantile hypothyroidism include feeding problems, failure to thrive, constipation, a hoarse cry, and somnolence. In... 

Birch, E.E., Garfield, S., Hoffman, D.R., Uauy, R., and Birch, D.G. (2000) A randomized controlled trial of early dietary supply of long-chain polyunsaturated fatty acids and mental development in term infants. Dev Med Child Neurol 42 174-181. 

Viggegal, G., Hagberg, B.S. and Laegreid, L., and Aronsson, M. (1993) Mental development in late infancy after prenatal exposure to benzodiazepines—a prospective study. J Child Psychol Psychiatry 34 295-305. 

When treating chronic conditions in children, pay special attention to tonifying the Kidney in order to support their physical and mental development. 

Infants with Iron Deficiency. B. l.o/off (Case Western Reserve University) and associates repotted that "Several consistent results have emerged from five studies of the behavior and development of infant with iron-deliciency anemia, a condition that affects at least 21) to 25 percent of the world s babies." All live studies used careful de lin it ions of iron status and included comparison groups without anemia All showed that infants with anemia scored lower on tests of mental development administered before treatment than infants without anemia did. 

Werner, H. Comparative Psychology of Mental Development. New York International Universities Press, 1957. 

Teratogenicity. Ability to cause dysmorphogenesis in the developing fetus. Behavioral teratogenicity. Ability to adversely affect the mental development of the fetus. 

Kjellstrom, T., P. Kennedy, S. Wallis, and C. Mantell. 1986. Physical and Mental Development of Children with Prenatal Exposure to Mercury from Fish. Stage 1 Preliminary Test at Age 4. Report 3080. Solna, Sweden National Swedish Environmental Protection Board. 

Non-thresholded chemicals that are not carcinogens are less frequently identified. For many years lead was considered to be thresholded because its effects on haemoglobin synthesis were not seen at low doses. However, recent work into the effects of lead on mental development suggest that there may be no threshold for this end-point. Food is a relatively minor source of lead exposure compared with air and dust in urban environments. For chemicals that relate to toxicological end-points that do not show thresholds it is not possible to identify a NOAEL or PTWI. In such cases it is desirable to estimate the level of risk associated with a given level of exposure. 

R.L. Naeye and E.C. Peters, Mental development of children whose mothers smoked during pregnancy, Obstet. Gynecol., 64(5) (1984) 601-607. 

Kjellstrom T, Kennedy P, Wallis S, Mantell C (1986) Physical and mental development of children with prenatal exposure to mercury from fish. Stage 1. Preliminary tests at age 4. Solna, National Swedish Environmental Board (Report No. 3080). 

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