Short-Term Memory

This software creates an experiment modeled after Sternberg's short-term memory scanning task. The purpose is to study how information is retrieved from short-term memory (STM) based on the subject's reaction time.

Applet

Instructions

Method

Each experiment has multiple trials, and each trial consists of the following for each of the six number of study items:

1. the presentation of study items, one at a time
2. the presentation of a test item
3. a response from the subject whether the test item was in the original list or not

There are a total of 11 variables which are explained below.

Choosing Experiment Variables

Number of Study Items - This will specify the number of study items that will be presented to the subject. Each trial will consist of presenting each one of the six specified number of study items. The number must be between 1 and a maximum of 1 less than the number of items in the study set. For the set of consonants, the maximum is 20.
Study - The default set consists of the set of consonants. You may specify a custom study set by typing a space-delimited list of study items in the textbox. The items may be words or keyboard characters.
Distractor Items - The default is to use the same set of items for both the study set and the set of distractors. A custom distractor set may be specified by typing a space-delimited list of items in the textbox. The distractor items may be words or keyboard characters, and may have common elements with the study set.
Item Duration - This is the time in milliseconds (1000ms = 1 second) that each study item will be shown to the subject. It may be any positive integer.
Delay Time - This is the time in seconds that the subject must wait between seeing the last study item and being presented with the test item. It may be any integer 0 or greater.
Number of Trials - This controls how many trials will be presented in the experiment. An integer greater than 0 is required.

Starting and Running the Experiment

To begin the experiment, press the Start Experiment button. The subject will be shown a "#####" before each trial. Before the test item is presented, the subject will be shown a "=====". The subject then presses the 'f' key or the 'j' key depending on whether or not they recall the test item being present in the study list.