1-17 The Development of the Brain (Part 2)

In their late teens, individuals will show a loss of significant numbers of brain cells in parts of the prefrontal cortex. At the same time, they will also show an increase in brain activity in these areas and improved cognitive ability—specifically, improvements in memory. The loss of less successful neurons and synapses make the brain more efficient.

Neurotrophins increase the branching of axons and dendrites in adults.

Fetal alcohol syndrome can occur in individuals who are exposed to high levels of ethanol in utero. The ethanol inhibits the release of glutamate—an excitatory neurotransmitter—during fetal development, and enhances the activity of GABA—an inhibitory neurotransmitter. Because of ethanol exposure, neurons receive less excitation than they normally would, receive fewer neurotrophins from incoming axons, and are more likely to undergo apoptosis.

Enriched environments stimulate dendritic branching.
Rats places in more stimulating environments show higher levels of dendritic branching as well as better performance on learning tests.

PET and fMRI studies have shown that blind people show activity in their occipital cortex when reading Braille, indicating that they are processing touch information in an area of the brain that is normally designated for visual processing.

In professional musicians, one area in the right temporal cortex is 30% larger than in non-musicians.

A protein that promotes the survival and growth of axons in the sympathetic nervous system and in certain parts of the brain

The self-destructive program that is initiated at a certain point in the development of a neuron unless the neuron is inhibited from killing itself

A chemical substance that promotes the survival and activity of neurons

A condition resulting from prenatal exposure to ethanol and marked by decreased alertness, hyperactivity, varying degrees of mental retardation, motor problems, heart defects, and facial abnormalities

A type of cramp experienced by musicians in which the touch receptors of two or more fingers overlap, leading to clumsiness, fatigue, and involuntary movements