in a memory study, the experimenter reads the same list of words to two groups. she asks group a to count the letters in each word, and she asks group b to focus on the meaning of each word for a later memory quiz. during a recall test, participants in group b recall significantly more words than participants in group a. memory researchers attribute this effect to differences in responses priming priming levels of processing levels of processing proactive interference proactive interference procedural memory procedural memory episodic memory