___________________________________________________________________________________________________________________ *Missing Scan Test* ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 04-03-2019 last updated: 08-11-2023 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 08-11-2023 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements a Missing Scan Test (MST) procedure based on the procedure described by Buschke (1963). Disclaimer: the procedure implemented is a best guess effort by Millisecond Software. In general the MST procedure presents lists of randomly ordered items (mostly numbers) of well known sets (Example: set 1-16) that leave out one set member (e.g. 5). Participants then have to name the missing set member. The MST procedure is believed to test item short term memory retention that is less subject to retrieval effects than recall/recognition tests. According to Bushke the MST method does not require retrieval by recall or recognition as it depends mainly on prior (well versed) knowledge of class membership. In order to correctly report the missing class member of such a well-known class, however, retention of all presented class members is still necessary and thus the MST can be used as a capacity measure for short term memory. Usually, the MST methodology uses lists of items that are greater in length than is used in digit span tests (e.g. N=13) and use items that are well-known such as lists of consecutive numbers. Reference Buschke, H. (1963). Retention in Immediate Memory Estimated without Retrieval. Science, New Series, Vol. 140, No. 3562 (Apr. 5, 1963), pp. 56-57 https://www.jstor.org/stable/1710736 ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ This script runs an MST task and Digit Span (DS) task* (optional). Order of task is determined by selected groupnumber. Both tasks are using the same stimuli lists which are generated at the beginning of each script run. By default, only the MST task is set to be run (see editable parameters). Participants are given a class of consecutive numbers of varying lengths (4, 6, 8, 10, 12, 14). The classes are taken from the numbers 1-16. Example class: '4, 5, 6, 7, 8, 9 ' Then participants hear a random order of these elements. However, one of the items is missing. Example presentation: "seven", "four", "five", "eight", "nine" MST: participants are asked to name the missing number (by default, the missing number is selected from a number dial) DS: participants are asked to name all the numbers that were presented, order is not important (by default, numbers are selected from a number dial) *the DS task is simplified: participants get the same stimuli lists as in the MST task and recalling the order of the items is not important (see Buschke, 1963) ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script* takes appr. 25-30 minutes to complete *by default, this script only runs the MST task. If the DS task is run duration will double. ___________________________________________________________________________________________________________________ DATA OUTPUT DICTIONARY ___________________________________________________________________________________________________________________ The fields in the data files are: (1) Raw data file: 'missingscantest_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. level: the currently tested level (length of sequence) missingNumber: the selected missing Number of the currently tested sequence (e.g. 6) class: the selected class (e.g. '5, 6, 7, 8') startNumber: the first class member lastNumber: the last class member presentationClass: the selected class in the randomly ordered presentation (e.g. 05080706) presentedNumbers: lists the presented numbers in order of presentation (missing number is not presented) enteredResponse: all the entered responses in the order entered (including those respones that might have been deleted) finalResponse: the final response given for the current trial Note: for DS trials the final values.finalResponse contains the ordered sequence of entered numbers (thus it may not reflect the order in which the items were named) correctResponse: the correct response for the current trial (Note: for DS trials it contains the ordered response) correct: accuracy of response: 1 = correct response; 0 = otherwise rt: the cumulative response time (in ms) of all trials that collected a number until the submit button is pressed/'done' measured from onset of first reponse collecting trial mainly used for debugging: parameter: debugMode: for data collection purposes this value should be 0 (if it's 1 participants will be able to see correct responses on the screen) sequenceLength: stores the length of the sequence (should be equal to values.level) theoreticalPresentedNumbers: the theoretically presented numbers (should be equal to values.presentedNumbers) (2) Summary data file: 'missingscantestSummary*.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) mst: retention span for the Missing Scan Test mstPropCorrectLevel4: stores the proportion correct responses for level 4 MST trials mstMeancorrRTLevel4: stores the mean reaction time for level 4 MST trials (correct trials only) (same for level6, level8, level10, level12, level14 trials) ds: retention span for the (simplified) Digit Span Test dsPropCorrectLevel4: stores the proportion correct responses for level 4 DS trials dsMeancorrRTLevel4: stores the mean reaction time for level 4 DS trials (correct trials only) (same for level6, level8, level10, level12, level14 trials) ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP (best guess effort) ___________________________________________________________________________________________________________________ This script is set up to run a Missing Scan Test (MST) and a Digit Span (DS) Assessment by default. The order of the tasks is counterbalanced by groupnumber: odd groupnumbers will run MST -> DS; even groupnumbers will run DS -> MST (Note: parameters.runDSAssessment controls whether the DS Assessment is run) Stimuli Preparation: At the beginning of the script, the script generates all the stimuli that are used for the MST/DS task: - the script generates stimuli for 90 trials: 15 trials for each of the 6 levels (4, 6, 8, 10, 12, 14) tested - the script randomly selects a level (4, 6, 8, 10, 12, 14) and randomly (without replacement) selects the missing number for the current level (1-15) (Note: each level runs numbers 1-15 once as the missing number) Example: level 4, missing number 5 - an algorithm randomly selects a suitable class/sequence for the selected level and selected missing number and randomizes the order of the numbers for presentation purposes. Note: the missing number is never 'a limiting number of the class' (Buschke, 1963) which Millisecond Software interpreted to be the highest number of the class. Example: class generated: '3, 4, 5, 6' => presentation class: '04050306' (the missing number '05' will not be presented) - the information is then added to several level specific lists (e.g. list.level4Class, list.level4_missingNumber, list.level4PresentationNumbers), so that MST and DS assessment run the very same stimuli for each level Response Format: By default, the stimuli are presented orally at 1 number per second and the response is collected in 'written' format (the numbers are selected from a number dial). Note: parameters.responseFormat can be set to collect oral responses. MST Task: (1) Demo: a minimum of one demo trial (level=3) is run to demonstrate the setup of the MST task (participants can decide whether they want to run additional demo trials) - the script randomly selects the missing number and generates a suitable class and random presentation order - the class is announced to participants (start button press starts the random sequence delivery) - the numbers are presented orally at 1 number per second - after a default delay of 0ms (editable parameter) the response is collected either in 'written' format (number selection from a number dial; default) or in verbal format (Response: missing number only) - participants receive feedback during the demo (2) Test: - the script randomly selects a level without replacement (levels: 4, 6, 8, 10, 12, 14; each tested 15 times) - the script randomly selects the missing number of the level as well as the generated class and random presentation order - the class is announced to participants (start button press starts the random sequence delivery) - the numbers are presented orally at 1 number per second in random order - after a default delay of 0ms (editable parameter) the response is collected either in 'written' format (number selection from a number dial; default) or in verbal format (Response: missing number only) - participants do not receive feedback during the test - after an intertrial interval (default: 500ms; editable parameters), the next class is presented DS Task: (1) Demo: a minimum of one demo trial (level=3) is run to demonstrate the setup of the MST task (participants can decide whether they want to run additional demo trials) - the script randomly selects the missing number and generates a suitable class and random presentation order - the class is announced to participants (start button press starts the random sequence delivery) - the numbers are presented orally at 1 number per second - after a default delay of 0ms (editable parameter) the response is collected either in 'written' format (number selection from a number dial; default) or in verbal format (Response: ALL the numbers presented; order is irrelevant) - participants receive feedback during the demo (2) Test: - the script randomly selects a level without replacement (levels: 4, 6, 8, 10, 12, 14; each tested 15 times) - the script randomly selects the missing number of the level as well as the generated class and random presentation order - the class is announced to participants (start button press starts the random sequence delivery) - the numbers are presented orally at 1 number per second - after a default delay of 0ms (editable parameter) the response is collected either in 'written' format (number selection from a number dial; default) or in verbal format (Response: ALL the numbers presented; order is irrelevant) - participants do not receive feedback during the test - after an intertrial interval (default: 500ms; editable parameters), the next class is presented Span Assessment: The assessment of the MST and the digit span was inspired by the method recommended by Woodworth and Schlosberg (1954): The script started with a base value of 2: MST: 2 + 2*x/15 (level4) + 2*x/15 (level6) + 3*x/15 (8) + 2*x/15 (10) + 2*x/15 (12) + 2*x/15 (14) DS: 2 + 2*x/15 (level4) + 2*x/15 (level6) + 3*x/15 (8) + 2*x/15 (10) + 2*x/15 (12) + 2*x/15 (14) => the span range possible with this algorithm: 2-14 Description of experimental setup in Buschke (1963): "The test items were the numbers from one to sixteen. Series containing 4, 6, 8, 10, 12, or 14 randomly ordered numbers were prepared so that in the 15 series for each number of items the missing number was randomly 1 through 15. This was achieved by using appropriate segments of the sequence one to sixteen as the classes from which one number was missing. The missing number was never a limiting number of the class. Before both digit-span and missing-scan tests the subjects were told the class or sequential series of numbers to which the numbers presented belonged." ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ Numbers 1-16, presented orally (using voiceover feature of text elements) __________________________________________________________________________________________________________________ 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: