Yantis1 Specs
This experiment was constructed from Folk2 with the following changes.
1. The basic task (is the target present?), the number of targets and distractors, and their colors, all remain the same. But in Yantis1 the target is always a single randomly selected digit (1-9) placed among the red letters (A-Z). Select a digit from 1-9 and place it randomly among the red letters.
2. The green distractors should be randomly selected digits (1-9).
3. There is no wave form played. The subject knows he is always looking for a red digit – any red digit -- and doesn’t need to be given any further instructions.
4. The display is presented for 2.0 seconds and then disappears. We are primarily interested in the subject’s accuracy rather than reaction time. The subject then distinguishes the displayed digit by clicking the appropriate digit on the displayed keypad.
5. Here is the complicated thing: on some trials, there is another task, in addition to the search. The task is to respond to 10 tones. The tones will be either high or low in pitch. The subject will respond to each tone with their left hand, by pressing S for high-pitched tone, and X for low-pitched tone. When the subject does this task, you present the tone (a 100-msec wavefile) and wait for the response. When the subject responds, you wait 100 msec before presenting the next tone. The visual display should be presented 100 msec after tone #6.
6. Here is the design. There are 4 blocktypes:
blocktype tone
task? Distractor condition
1 No Static green distractors
2 Yes Static green distractors
3 No Flickering green distractors
4 Yes Flickering green distractors
There should be 12 blocks each composed of 20 trials per block. At the beginning of the block in which there will be a tones task, tell the subject (4-second display followed by 2-second blank period) “There will be a tone task in this block. Please prepare for both tasks.”
The following is a list of headers for the resulting data fields in the order they appear in the data files.
trialNumber, BlockNumber, blockType, orderCondition,
targetNumber, targetPosition, targetPositionX, targetPositionY, userAnswer,
tonesTrial, completed, numTonesCorrect, avgResp
For clarification:
userAnswer: 0 for wrong, 1 for correct
tonesTrial: 1 for a trial type with tones test, else 0
completed: number of tones that were played
avgResp: average response time per tone in ms