The definition of abnormal psychology includes the practice of

Evidence suggests that during wakefulness a sleep-promoting chemical is produced and builds up in the blood until the person becomes tired and falls asleep.

a. true b. false

Collectively known as ________, these conditions are defined by academic achievement below expectations for age, years in school, and IQ.

a. thinking disorders b. mental retardation c. specific learning disorders d. pervasive developmental disorders