___________________________________________________________________________________________________________________ SIMPLE REACTION TIME TASK - visual ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC last updated: 01-07-2025 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 01-07-2025 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script runs a simple visual reaction time task. ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ The participant gets presented a fixation cross that is followed after variable time intervals by a visual target stimulus (here: circle). The participant's task is to press the spacebar as soon as the target stimulus appears on the screen. Latency, mean latency, and latency standard deviation are recorded in the data file. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 4 minutes to complete ___________________________________________________________________________________________________________________ DATA OUTPUT DICTIONARY ___________________________________________________________________________________________________________________ The fields in the data files are: (1) Raw data file: 'srtvisual_raw*.iqdat' (a separate file for each participant) build: The specific Inquisit version used (the 'build') that was run computer.platform: the platform the script was run on (win/mac/ios/android) date, time: date and time script was run subject, group: with the current subject/groupnumber session: with the current session id blockCode, blockNum: the name and number of the current block (built-in Inquisit variable) trialCode, trialNum: the name and number of the currently recorded trial (built-in Inquisit variable) Note: trialNum is a built-in Inquisit variable; it counts all trials run; even those that do not store data to the data file such as feedback trials. Thus, trialNum may not reflect the number of main trials run per block. stimulusItem: the first presented stimulus (=fixation cross) (parameter) focusx: the x-coordinate of the fixation cross (parameter) focusy: the y-coordinate of the fixation cross (parameter) focuscolor: the color of the fixation cross (parameter) focussize: the size of the fixation cross stimulusItem: the second presented stimulus (=target) (parameter) targetcolor: the current color of the target circle (parameter) targetsize: the current color of the target circle (parameter) targetx: the x-coordinate of the target circle (parameter) targety: the y-coordinate of the target circle (parameter) fixed: 0= fixed position of target; 1 = random position of target (parameter) maxtrialnumber: the number of trials in a block trials.srtt.count: counts the SRTT trials run in a given block stimInterval: the current stimulus interval latency: the latency of the response (in ms) trial.srtt.meanLatency: the mean latency in the current block (in ms) trial.srtt.medianLatency: the median latency in the current block (in ms) trial.srtt.minLatency: the fastest response in the current block (in ms) trial.srtt.maxLatency: the slowest response in the current block (in ms) trial.srtt.sdLatency: the standard deviation of the latency responses in the current block trial.srtt.varLatency: the variance of the latency responses in the current block trial.srtt.totalMeanLatency: the mean latency across all trials.SRTT (in ms) trial.srtt.totalMedianLatency: the median latency across all trials.SRTT (in ms) trial.srtt.totalMinLatency: the fastest response across all trials SRTT (in ms) trial.srtt.totalMaxLatency: the slowest response across all trials SRTT (in ms) trial.srtt.totalSDLatency: the the standard deviation of the latency responses across all trials SRTT trial.srtt.totalVarLatency: the variance of the latency responses across all trials SRTT (2) Summary data file: 'srtvisual_summary*.iqdat' (a separate file for each participant) inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startDate: date script was run startTime: time script was started subjectId: assigned subject id number groupId: assigned group id number sessionId: assigned session id number elapsedTime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run) trial.srtt.totalMeanLatency: the mean latency across all trials.SRTT (in ms) trial.srtt.totalMedianLatency: the median latency across all trials.SRTT (in ms) trial.srtt.totalMinLatency: the fastest response across all trials SRTT (in ms) trial.srtt.totalMaxLatency: the slowest response across all trials SRTT (in ms) trial.srtt.totalSDLatency: the the standard deviation of the latency responses across all trials SRTT trial.srtt.totalVarLatency: the variance of the latency responses across all trials SRTT ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ * By default, the script runs 2 blocks of 20 trials each * By default, the fixation cross as well as the target stimuli appear in the center of the screen. Changes can be made under section Editable Parameter, including changing the script so that the target stimuli appear randomly in one of 9 screen positions. * By default, the time intervals are randomly chosen from 2000ms, 3000ms, 4000ms, 5000ms, 6000ms, 7000ms, 8000ms * By default, the fixation cross is black. * By default, the color of the circle is red. * By default, the color of the screen background is white. ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ see section Editable Instructions ___________________________________________________________________________________________________________________ EDITABLE CODE ___________________________________________________________________________________________________________________ check below for (relatively) easily editable parameters, stimuli, instructions etc. Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment. The parameters you can change are: targetColor: sets the color of the circle; the default is red targetSize: sets the size of the circle; the default is 10% of the vertical screen targetx: sets the x-coordinate of the target circle ; the default is the center (50%) targety: sets the y-coordinate of the target circle , the default is the center (50%) focusx: sets the x-coordinate of the focus stimulus; the default is the center (50%) focusy: sets the y-coordinate of the focus stimulus; the default is the center (50%) focusColor: sets the color of the focus stimulus; the default is black focusSize: sets the size of the focus stimulus maxTrialNumber: sets the number of trials that should be run in a block; the default is 20 screenColor: sets the background color of the screen fixed: determines whether to use the fixed coordinates for the target stimulus (= 0) or to select randomly from 9 different screen positions (=1) ; default is 0