Shane, who is 4 years old, had stolen some money lying on the coffee table three days ago. Ever since he stole the money, Shane has been a little gloomy. When Shane's mother informed him that he will not be able to watch his favorite cartoon show, as they were expecting guests that evening, Shane felt he deserved this as punishment for stealing and did not throw a tantrum. Shane's acceptance of his mother's word without a tantrum reflects the operation of ________ in this scenario.

Which of these helps explain why people continue an addiction, despite harm to their lives?

a. As tolerance to the substance increases, the pleasure increases also b. People tend to forget how unpleasant the withdrawal symptoms can be. c. The nucleus accumbens gradually becomes less sensitive to the substance. d. The person learns to use the substance to relieve distress.

In which of the following situations would the risk of developing schizophrenia be the lowest for a child?

a. A child's schizophrenic parent has a non-schizophrenic identical twin. b. A child's non-schizophrenic parent has a schizophrenic identical twin. c. A child's schizophrenic parent has a non-schizophrenic fraternal twin. d. A child's non-schizophrenic parent has a schizophrenic fraternal twin.