People who lived in New York City during the 9/11 terrorist attack on the World Trade Center experienced shared challenges due to the attack that are called __________ effects

Immediately before sleep the EEG shifts to patterns of larger and slower waves called __________ waves.

a. alpha b. beta c. delta d. spindle

After surviving an Amtrak derailment, John experienced frequent, vivid thoughts and images of the accident for several months. He also had problems sleeping and was irritable and withdrawn. John is suffering from ________

a. major depression. b. posttraumatic stress disorder c. generalized anxiety disorder. d. panic disorder.