Through The Ages

CONCEPTION TO BIRTH PRENATAL The brain and nervous system develop and form an intricate network. But genetic errors and environmental factors like fetal exposure to alcohol or drugs can make this process go awry. Some common examples:

CEREBRAL PALSY Affects about 10,000 U.S. babies a year. More than 80% show signs in the womb or before they are a month old. Usually diagnosed by age 3

FETAL ALCOHOL SYNDROME Profound mental retardation caused by maternal alcohol abuse. Studies suggest that 1,200 to 8,800 FAS babies are born in the U.S. every year

NEURAL-TUBE DEFECTS These include spina bifida and anencephaly, each of which affects 1 or 2 of every 10,000 live births

DOWN SYNDROME The most common chromosome abnormality. Occurs in 1 of every 800 to 1,000 live births

INFANCY 0-5 yrs. Excess neurons and synapses are pruned in the first 18 months, but the brain keeps growing, reaching 90% of adult size. Brain cells become more adept at communicating; babies learn to talk

AUTISM DISORDERS Three to four times as common in boys

EPILEPSY About 10% of Americans will have a seizure sometime during their life. By age 80, about 3% will have been found to have epilepsy

ANTISOCIAL BEHAVIOR From lying and bullying to vandalism and homicide. More prevalent in boys, who tend to inflict physical harm on others

ATTENTION-DEFICIT/HYPERACTIVITY DISORDER Tends to run in families and affects two to three times as many boys as girls. Between 3% and 5% of U.S. schoolchildren are thought to have ADHD

DYSLEXIA Revealed when a child tries to learns to read

ANXIETY DISORDERS Most prevalent group of psychiatric illnesses among children and adults

LATE CHILDHOOD 5-10 yrs. Dramatic growth spurts in the temporal and parietal lobes, brain regions crucial to language and understanding of spatial relations, make this a prime time for learning new languages and music

DEPRESSION In any given year, nearly 10% of adult Americans-two-thirds of them women-experience a depressive disorder. Up to 10% of children ages 6 to 12 have symptoms of major depression, but the typical age of onset is mid-20s

CONDUCT DISORDER Various behaviors that show a persistent disregard for the norms and rules of society. Affects 6% to 16% of boys and 2% to 9% of girls under age 18

PUBERTY 10-13 yrs. Just before puberty, the brain's gray matter thickens, especially in the frontal lobe, the seat of planning, impulse control and reasoning. This growth may be triggered by surges of sex hormones

EATING DISORDERS In the U.S., most common in teen girls and young women; only 5% to 15% of anorexics or bulimics and 35% of binge eaters are male

OBSESSIVE COMPULSIVE Apparently caused by abnormally functioning brain circuitry. Neurotransmitter and hormone imbalances may also be involved

ADOLESCENCE 13-20 yrs. The brain begins to shrink, losing about 2% of its weight and volume in each successive decade. Abnormally high loss of gray matter during this period may be a cause of teenage schizophrenia

AGORAPHOBIA Affects twice as many women as men

PANIC DISORDER Afflicts 2.4 million Americans ages 18 to 54 in a given year. Twice as common in women