___________________________________________________________________________________________________________________ *Memory Scan Task* (subtest of COGDRAS) ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 09-09-2020 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 Memory Scan 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 view an initial triplet of digits (presented serially, one after other). They then view a series of 18 digits and have to decide whether the digit was one of the three by pressing a Yes or a No-key. ___________________________________________________________________________________________________________________ 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: 'memoryscan_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. trialCode: "target" vs. "foil" targetDigits: the three target digits stimulusItem: the presented digits response: the participant's response (scancode of response buttons) 16 = Q 25 = P 57 = spacebar responseLabel: "yes" vs. "no" responseCategory: "Hit" (pressed yes-key for a target digit) "Miss" (pressed no-key for a target digit) = omission error "CR" (pressed no-key for a foil digit) = correct rejection "FA" (pressed yes-key for a foil digit) = commission error correct: accuracy of response: 1 = correct response; 0 = otherwise latency: the response latency (in ms); measured from: onset of words (2) Summary data file: 'memoryscan_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) msAcc: proportion correct recognition (across old and new words) in Immediate Word Recognition Test msRT: mean response time (in ms) of correct responses (across old and new words) during recognition phase in Immediate Word Recognition Test msHitRT: mean response time (in ms) of correct responses for old words only rHIT: the hitrate (proportion correct responses for old words => participant said 'yes' to old words) rFA: the false alarm rate (proportion of incorrect responses for new words => participants said 'yes' to new words) msAPrime: non-parametric measure of sensitivity in Immediate Word Recognition Test Range: 0 (all incorrect responses) - 0.5 (random responses) - 1 (all correct responses) For Aprime measure see: Stanislaw, H. & Todorov, N. (1999). Calculation of signal detection theory measures. Behavior Research Methods, Instruments, & Computers, 1999, 31 (1), 137-149. Note: Nicholl et al (1995) used the non-parametric signal theory index (SI) presented by Frey and Colliver (1973) with a range of -1 (all incorrect) to 1 (all correct) ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ (1) Target Digit Learning - three digits are randomly (without replacement) selected from 1-9 Note: this script places the following constraint on the sampling process: The last sampled digit cannot be the third of three consecutive digits. Example: targetdigit = 4, targetdigit2 = 3 => the third targetdigit cannot be 2 nor 5. - each digit is presented for 2500ms (duration parameters editable, see section Editable Parameters) (2) MS Test - 18 trials: digits 1-9 are randomly selected Note: trial 1-9 randomly samples digit 1-9 (without replacement); trial 10-18 randomly samples 1-9 (without replacement) => 6 target trials; 12 foil trials (target:foil = 1:2) - digits are presented as long as needed to make response ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ provided by Millisecond Software - can be edited under section Editable Stimuli The size of the presented digits 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 = 18 //the number of test trials run (default: 18) //Duration Parameters: / firstStimDelay = 1000 //the delay (in ms) of the first stim after pressing spacebar to start / soa = 2500 //stimulus onset asynchrony (in ms) of the target triplets (default: 2500ms) / stimDuration = 2500 //the duration (in ms) that each target digit is presented (default: 2500ms) //Note: stimDuraton cannot exceed SOA //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