Chapter 1. Release from PI

Introduction

In this experiment, you will be asked to remember three words. You will have to hold those words in your memory, after which you will have to type as many of those words as you can recall. Do your best to recall these words and please type your answers carefully.

Experiment Setup

Instructions

You will be presented with a list of three words. The list will be shown briefly. Your task will be to remember the words. There will be an intervening period, or delay, before you are asked to recall them. During this delay you will need to perform a task or set of task. If a number appears on the screen; immediately start counting backward by threes out loud as fast as you can from that number. If you lose track or forget the number, pick a different number and start over. It is vital that you do this task as quickly as you can.There will be a beeping tone to indicate the speed at which you should try to count. Do your best to keep up. In no case should you stop. If is a dot and a box on the screen; move your mouse to track the dot. If you see a number and the dot and box, you will have to simultaneously carry out both tasks. For this experiment to work, it is vital for you to be completely engaged in these intervening tasks.

After this intervening period, you will be shown three blank lines. Please type in the three words, one word per line, that you recall from the list just presented to you. When you are done, press the Done button and continue onto the next word list.

You will be presented with six lists.

Experiment

Results

Debriefing

This experiment examines one of the many causes of forgetting: proactive interference. Proactive interference is where earlier learned information leads to worse recall of later learned information. Remembering a list of three words should not be too difficult, right? Think about the first list of fruit. Typically people do very well in the recall of the first list. But if you then have to remember more lists of fruit, it begins to become confusing which words were presented on the most recent list. The fact that you do worse as you are given more lists to remember is what makes this proactive interference. (There is also retroactive interference; that is where later learning makes it harder to recall previously learned information.) This Proactive Interference experiment relies on the fact that the words in the first five trials are all drawn from the same category – in this case, fruit. We can see how category membership is the critical variable here because when on the last trial the list shifts from fruit to tools, suddenly your recall gets much better. This is the release from proactive interference. The finding that category membership can cause proactive interference fits with other experiments, some in this collection, that suggest that items in memory are stored in interconnected ways. In this experiment, one of the ways items in memory are connected is by the category they belong to.

References:

Ferraro, F., & King, B. (2004). Release from proactive interference with positive and negative words. The Psychological Record, 54(2), 199-206.

Wickens, D. D., Born, D. G., & Allen, C. K. (1963). Proactive inhibition and item similarity in short-term memory. Journal of Verbal Learning & Verbal Behavior, 2(5-6), 440-445.

Quiz