Social Neuroscience

Glossary

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Menkes disease -- A copper-deficiency disorder affecting 1:100,000 newborns, Menkes disease results in irreparable harm to the brain and nervous system. Children with Menkes disease typically die during the first decade of life. Caused by a defect in the gene ATP7A on the X chromosome that regulates copper levels in the body, leading to abnormally low levels of copper in the brain and liver as well as excessive amounts of copper in the kidneys and intestines. Low levels of copper in the brain lead to deficient myelin formation. Affected children may experience seizures and below normal body temperature. Many also have distinctive kinky hair, which is steel-colored or colorless and is easily rubbed off the skull. Symptoms of Menkes disease usually appear as developmental delays around 2 to 3 months of age. By that time, however, the copper deficiency has already caused significant brain damage. Treatment consists of injections of a copper-containing drug, but must be initiated early and for a 2-3 year period to be effective. Research is currently being conducted to develop tests to detect the disease in newborns (see Kaler, Stephen G., et al. 2008. Neonatal Diagnosis and Treatment of Menkes Disease. NEJM 2008 Feb 7; 358(6): 605-614 ).

Myelin -- an insulating material that surrounds certain types of brain and nerve cells, enabling electrical transduction along the length of a neuron. The deposition of myelin around brain and nerve cells is nearly completed by age 2. Related disorders: Muscular dystrophy, Menkes disease.

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Termination period -- In developmental neuroscience a term coined by Warkany to refer to: "the time in development of an organ after which a specific malformation cannot occur by any teratogenic mechanism." The event leading to a malformation can occur prior to, but no later than, this given time period(Volpe 2001).