A box used in operant conditioning of animals, which limits the available responses and thus increases the likelihood that the desired response will occur, is called a ________ box

A 3-month-old infant who sucks her thumb, discovers that it is pleasurable, and sucks it again is demonstrating Piaget's concept of ______ circular reactions

Fill in the blank with correct word

. Because they have similar chemical structures, morphine and other opiates are able to lock into receptor sites for _____

A) GABA B) serotonin C) dopamine D) endorphins