Which principle of perception may explain why we tend to mentally group together people from a particular country or geographic region?

A boy is teaching his younger sister how to make her bed. At first, he tells her she did a good job if she gets the bedspread pulled up, even if the sheets are still rumpled. Each following day,

he encourages her to be a little neater before telling her she did a good job. The boy may not know it, but he is using a. secondary reinforcement. b. primary reinforcement. c. a fixed-interval schedule. d. shaping by successive approximations.

Procedural memories are dependent upon the amygdala

a. True b. False