Phenothiazines, a group of drugs used to treat schizophrenia, block the action of dopamine. A severe side-effect of this medication, if used over a long period of time, could be

Fred is afraid of spiders. He won't even watch a nature show on TV about them. When he sees a picture of a spider, he has a panic attack, but when he avoids looking at the image, his panic goes away. Fred's avoidance of spiders is being __________________

a) extinguished, because he feels anxious after doing so b) recovered spontaneously, because he will never get better c) positively reinforced, because he is rewarded by his anxiety going down d) negatively reinforced, because he is rewarded by his anxiety going down

Twins occur more often among __________ women than __________ women

A) white; black B) Asian; black C) tall; short D) younger; older