___________________________________________________________________________________________________________________ *Choice Reaction Time Task* (subtest of COGDRAS) ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 09-08-2020 last updated: 02-10-2025 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-10-2025 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements a Choice Reaction Time Task, a subset of the Cognitive Drug Research Computerized Assessment System (COGDRAS). Reference Nicholl, C.G. et al (1995). THE COGNITIVE DRUG RESEARCH COMPUTERIZED ASSESSMENT SYSTEM IN SPEED OF THE ESSENCE? THE EVALUATION OF EARLY DEMENTIA. INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, VOL. 10: 199-206. ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants are asked to press a certain response key (here: Q) whenever the word YES appears in the middle of the screen or press another response key (here: P) whenever the word NO appears. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 2 minutes to complete Note: the test can easily be aborted by pressing "Ctrl+Alt+A" __________________________________________________________________________________________________________________ DATA OUTPUT DICTIONARY ___________________________________________________________________________________________________________________ The fields in the data files are: (1) Raw data file: 'choicereactiontime_cogdras_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. countTrials: custom counter of test trials (those that present word "YES") stimulusItem: the presented stimuli in order of trial presentation response: the participant's response (scancode of response buttons) 16 = Q responseLabel: "yes" or "no" correct: 1 = correct response 0 = error response latency: the response latency (in ms); measured from: onset of word YES iti: the intertrial interval (in ms) run at the end of the current trial (2) Summary data file: 'choicereactiontime_cogdras_summary*.iqdat' (a separate file for each participant)* inquisit.version: the Inquisit build/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) crtAcc: the overall proportion correct responses in the Choice Reaction Time test (across yes/no trials) crtRT: the mean response time (in ms) of correct responses in the Choice Reaction Time test (across yes/no trials) (measured from onset of word 'YES'/'NO' in the center of the screen) ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ 1. Test - 20 trials (editable parameters) - half the trial present YES, the other half NO (order is randomly determined, see list.trialselector) Trial sequence: - word YES/NO appears (wait for response) -> random iti (1000-2500ms) -> word YES.... ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ provided by Millisecond Software - can be edited under section Editable Stimuli The word YES/NO - size can be set under section Editable Parameters ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ provided by Millisecond Software - can be edited under 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: //StimSize: / stimSize = 20% //the proportional sizing of the yes/no-word on screen (default: 20%) //Experimental Design Parameters: / nrTestTrials = 20 //the number of test trials run (default: 20) //Response Keys: / leftKey = "Q" //the left response key (here: Q) / rightKey = "P" //the right response key (here: P) / yesKey = parameters.leftKey //the assignment of left/right key to the yesKey (here Q); left keys will appear on the left on touch screens / noKey = parameters.rightKey //the assignment of left/right key to the noKey (here P); right keys will appear on the right on touch screens