___________________________________________________________________________________________________________________ Number Vigilance Task (German Version) ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 09-25-2017 last updated: 02-25-2022 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-25-2022 Millisecond Software German translation provided by K. Borchert for Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements a computerized Number Vigilance Task, a measure of attention and cognitive control. The Number Vigilance Task is used as a subtest of the Cognitive Drug Research Computerized Assessment System (COGRAS). The Number Vigilance Task is a type of go/no go task with digits. The implemented procedure is similar to the one published in: Nicholl, C.G. et al (1995). The the Cognitive Drug Research Computerized Assessment System in the evaluation of early dementia- is speed of the essence? INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, VOL. 10: 199-206 Adjustments to z-scores as described by: Gregg, A. & Sedikides, C. (2010). Narcissistic Fragility: Rethinking Its Links to Explicit and Implicit Self-esteem, Self and Identity, 9:2, 142-161 (p.148) ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants view a stream of digits presented in the middle of the screen, one at a time. A new digit is presented ~750ms (for a presentation rate of: 80 words/minute). Whenever the digit is the same as the target digit (which is presented on the right of the screen throughout the task), they have to press the Spacebar. Otherwise they are instructed to not do anything but stay vigilant and wait for the next digit. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 3 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'numbervigilance_german_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. digitType: 1 = target digit (current digit = target digit); 2 = foil digit (current digit <> target digit) targetDigit: the randomly selected target digit that is presented at the right of the screen currentDigit: the currently randomly selected digit that is presented in the center of the screen response: the participant's response (scancode of response button) 57 => spacebar was pressed; 0 = no response responseCategory: "hit" (pressed spacebar for a target) "miss" (did not press spacebar for a target) = omission error "CR" (did not press spacebar for a nontarget) = correct rejection "FA" (pressed spacebar for a nontarget) = commission error correct: accuracy of response: 1 = correct response; 0 = otherwise latency: the response latency (in ms); measured from: onset of center digit (2) Summary data file: 'numbervigilance_german_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) propCorrect: overall proportion correct (across all test trials) parameters.nrTestTrials: the number of test trials run (default: 100) parameters.targetRate: the proportion of targets (signals) during the test (and practice) (default: 25%) list.hits.itemCount: the number of target (signal) trials during the test HITrate: hitrate (across test trials that presented a target digit) = pressed spacebar for a target FArate: false alarm rate (across test trials that presented a foil digit) = pressed spacebar for a nontarget Note: z-score calculations: adjustments (see Gregg & Sedikides, 2010, p.148) If the hit rate / FA rate is 0 => 0.005 is used instead (aka 0.005 is added to the hit/FA rate) IF the hit rate / FA rate is 1.0 => 0.995 is used instead (aka 0.005 is subtracted from the hit/FA rate) z-score of Hit Rate: z-score of hit rate z_FArate: z-score of false alarm rate dprime: d' = sensitivity index calculated as difference btw. z score of hit rate and z-score of false alarm rate => Range (in this script): -5.1516586840152740479 <= dprime <= 5.1516586840152740479 (=perfect performance) => The higher the value, the better signals (=targets) were overall distinguished from noise (=nontargets) and thus the better participant paid attention (d' = 0: chance performance; negative d-primes: participant treated nontargets as targets and targets as nontargets) hitRT: the mean hit latency (in ms) * separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section DATA ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ Target Digit: is sampled randomly at the start of the script. The same target is used for practice and test session. 1. Practice Block: (optional) - number of practice trials can be set under section Editable Parameters (default: 20) Note: if set to 0, the practice trials are skipped. Instructions automatically adapt. - proportion of target trials can be set under section Editable Parameters (default: 25%) - order of target and foil trials is random - selection of foil digits is random with replacement - SOA and digit presentation duration can be set under section Editable Parameters (SOA: 1000ms; digit presentation duration: 1000ms) 2. Test Block: - number of test trials can be set under section Editable Parameters (default: 100) - proportion of target trials can be set under section Editable Parameters (default: 25%) - order of target and foil trials is random - selection of foil digits is random with replacement - SOA and digit presentation duration can be set under section Editable Parameters (SOA: 750ms; digit presentation duration: 750ms) Trial Sequence: * target is presented throughout the blocks to the right on the screen * each block starts with the target presented alone for duration SOA current digit presentation (750ms), response window = SOA = 750ms ->current digit presentation ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ target = randomly determined digit from 0 to 9, presented in black font on the right side of the screen current digit = digit from 0 to 9, presented in black font in the center of the screen both digits are equal in size (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: /digitSOA_practice: the stimulus onset asynchrony (in ms) during practice trials (default: 1000ms) Note: participants have the entire SOA to respond /digitPresentationTime_practice: the presentation duration (in ms) of the current trial digit (default: 1000ms) Note: if digitPresentationTime_practice > digitSOA_practice, it's automatically set to digitSOA_practice /digitSOA_test: the stimulus onset asynchrony (in ms) during practice trials (default: 750ms) Note: participants have the entire SOA to respond Note: 1 word/750ms => 80 words/minute /digitPresentationTime_test: the presentation duration (in ms) of the current trial digit (default: 750ms) Note: if digitPresentationTime_practice > digitSOA_practice, it's automatically set to digitSOA_practice /errorFeedbackDuration: the duration (in ms) of the error feedback during practice (default: 5000ms) /readyDuration: the duration (in ms) of the 'get ready trial' (default: 5000ms) /nrPracticeTrials: the number of practice trials run (default: 20) Note: uses the same target: foil rate as the test Note: if set to 0, the practice session is simply skipped /nrTestTrials: the number of test trials run (default: 100) /targetRate: the proportion of targets during the test (and practice) (default: 25%) Note: the proportion of targets should result in an integer Example: 100 test trials * 0.25 targets = > 25 targets /targetDigitSize: the proportional size of the digits on screen (default: 20%) Responsekeys: /responseKey: the response key (default: " " -> spacebar)