Ch15 - Module 2

Disorders of Development

What is a teratogen?

What is a teratogen?

any chemical or toxin that detrimentally impacts the development of an embryo [Rubella, Zika - microcephaly]

Can a women drink alcohol when pregnant?

As of the 3rd or 4th week, alcohol can cause intellectual disability; A single drinking binge can cause severe damage

What are the effects of alcohol consumption on babies?

1. Babies are smaller than average

2. Babies develop slowly

3. Can develop fetal alcohol spectrum disorder

How does alcohol interrupt brain developmental?

• Interference with the neural adhesion protein which guides neuron growth

• Direct effect on neural plasticity

Can neuron growth be affected by father?

Alcohol consumption of father affects BDNF & NGF (nerve growth factors)

There are at least a hundred different inherited metabolic disorder that can affect the development of the brain but the most common is ____________

phenylketonuria (PKU)

What causes PKU?

an inherited lack of an enzyme that converts phenylalanine into tryosine. this creates an excessive amount of phenylalanine in the blood that affects myelination in the CNS and lowers IQ

How is PKU treated?

Dietary restrictions to foods containing phenylalanine

What is pyridoxine dependency?

• a genetic error of metabolism that damages the cerebral white matter, thalamus, and cerebellum

• treated with a large dose of Vitamin B6

What is galactosemia?

• a genetic error that makes one unable to metabolize galactose (milk sugar) and damages cerebral white matter and cerebellum

• treated with a sugar free milk substitute

What is Tay-Sachs disease?

• Occurs mainly in Eastern European children of Jewish decent

• causes brain swelling and damage from the skull on its folds

• Begins by 4 months of age

• Eggaerated startle response to sounds, listlessness, irritability, spasticity, seizures, dimentia, and death

• one of several untreatable metabolic storage disorders

What is down syndrome?

a congenital disorder (present at birth) that results in abnormal brain development and impaired intellectual disability

What causes down syndrome?

the presence of an extra 21st chromosome due to the mother’s age (over 35 years old)

What are the features of a down syndrome brain?

• learn to speak by 5

• brain is 10% lighter

• smaller, less folded convolutions

• smaller frontal lobes

• thinner superior temporal gyrus

• development of abnormal microscoic structures after 30

• brain degeneration in adulthood that resembles Alzheimer’s