Memory Laboratory Homework

Dr. Robert Goldstone

Psychology Department/ Program in Cognitive Science

Indiana University

1. Conduct an experiment to look at proactive interference, following these steps:
A. Create a list of 15 nonsense words (or use the 15 “initial set” words at http://cognitrn.psych.indiana.edu/rgoldsto/courses/memorywords.htm), and show them one at a time to someone for about 4 seconds each.
B. Count the number of nonsense words that they recalled.
C. Repeat Steps A and B one more time, with a new list of nonsense words (or the second set of words for Question 1), recording the number of words recalled.
D. Is the number of words recalled for the two lists expected by proactive interference? If so, explain why. If not, describe a theory that would predict your results.

2. Conduct an experiment to look at retroactive interference, following these steps:
A. Create a list of 15 nonsense words (or use the initial set of words for Question 2 at http://cognitrn.psych.indiana.edu/rgoldsto/courses/memorywords.htm), and show them one at a time to someone for about 4 seconds each. Remind your subject that they will have to remember these words later. Call this List A. Count the number of List A words that your subject recalls.
B. Create a new list of 15 nonsense words (or use the second set of words), and show them to your subject for about 4 seconds each. Call this List B. Count the number of List B words that they can recall.
C. Tell your subject to recall as many words from List A that they can. Is the number less than or more than the number of List A words that they recalled before? Is this result consistent with retroactive interference? Specifically, what in your results is consistent/inconsistent with retroactive interference?
D. Given your results from Question #1, is retroactive interference stronger or weaker than proactive interference? What in your results indicates this?
E. Any evidence for retroactive interference that you may have found in Step C is also consistent with simple decay of memory over time (rather than intererence of List A due to List B). You don't have to run another experiment, but describe how you could create an experiment to unambiguously tell whether a person showed retroactive interference or simple decay. Describe how you would present the words in enough detail that we can tell that this final condition, combined with Steps A-C, allows you to get clear evidence regarding intererence and decay.

3. According to context-reinstatement, memory is best when the situation during study closely resembles the situation during test. Design an experiment to test this using RECOGNITION memory (not recall), by manipulating the kind of voice (e.g. high versus low pitch. You don’t have to have two speakers. You can say all the words yourself, just using two distinct voices) you use to read the words to your subject. So, is your subject more likely to recognize the word “street” as being old if you say it with the same voice that you initially said it? You will need to compare a condition with the SAME voice during study and test with one that has DIFFERENT voices during study and test. Describe how you formed each condition. You can use words that you create yourself, or you can use the Question 3 word lists at http://cognitrn.psych.indiana.edu/rgoldsto/courses/memorywords.htm. These word lists are helpful because they contain an original word list of 10 words, and a new word list that has all 10 words plus 10 new words. Report your subjects results for each condition. Do these results support context-reinstatement. Why or why not?