In adult humans, successive exposures to amphetamine have been ...

[saraeharris]

In adult humans, successive exposures to amphetamine have been shown to produce
 
  a. intensification of most of its subjective effects
  b. tolerance to all of its subjective effects
  c. intensification of some of its effects while other effects exhibit tolerance
  d. virtually no tolerance to amphetamine's subjective effects

Question 2

Drugs typically classified as psychostimulants
 
  a. exhibit inverted U-shaped dose-response functions with respect to their performance enhancing effects
  b. only enhance performance of fatigued subjects or those with symptoms of attention deficit disorders
  c. generally increase the activity of neurons throughout the CNS
  d. all of these

[bigcheese9]

Answer to Question 1

c

Answer to Question 2

a