Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 17, 2017
Last Modified: January 15, 2023 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements a child friendly Global-Local-Task; a test of perceptual processing of global and local features of stimuli.
The implemented procedure is based on:
Sjöwall, D., Roth, L., Lindqvist, S., & Thorell, L. B. (2013). Multiple deficits in ADHD: executive dysfunction, delay aversion, reaction time variability and emotional deficits. Journal of Child Psychology and Psychiatry, 54, 619–627.
7 minutes
Participants see Navon figures made up of an overall shape (circle vs. square) and detail shapes (circle vs. square). They work through 3 different rounds: (a) pay attention to global shape; (b) pay attention to local shape (c) a mixed design (measures shifting).
1. Block*: global task
- 10 practice trials (don't count toward summary statistics)
- 20 test trials (test trials are indistinguishable from practice trials)
- smiley feedback provided
- each of the two test stimuli is selected equally often during the test trials (order is randomized)
2. Block*: local task
- 10 practice trials (don't count toward summary statistics)
- 20 test trials (test trials are indistinguishable from practice trials)
- smiley feedback provided
- each of the two test stimuli is selected equally often during the test trials (order is randomized)
order of global/local tasks is randomized.
3. Block: mixed (assesses shifting costs)
- 11 practice trials (1 starttrial + 10 shift/nonshift trials) - don't count toward summary statistics
- the starttrial selects the first task randomly
- 40 test trials: 20 shift + 20 nonshift trials (order is randomized)
- smiley feedback provided
- each of the two test stimuli is selected equally often during the test trials (order is randomized)
- the starttrials
Trial Sequence:
stimulus -> until response -> Feedback (500ms) -> ITI (500ms)
provided by Millisecond:
Sizing can be controlled via an editable parameter
provided by Millisecond - can be edited under section Editable Instructions
The instructions are presented in slide format. Slides can easily be customized in PowerPoint.
File Name: globallocaltask_children_mi_summary*.iqdat
| Name | Description |
|---|---|
| inquisit.version | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| startDate | Date the session was run |
| startTime | Time the session was run |
| subjectId | Participant ID |
| groupId | Group number |
| sessionId | Session number |
| elapsedTime | Session duration in ms |
| completed | 0 = Test was not completed 1 = Test was completed |
| accGlobal | Proportion correct across all global test trials (block.global only) |
| meanRTGlobal | Mean correct latency (in ms) of all global test trials (block.global only) |
| accLocal | Proportion correct across all local test trials (block.local only) |
| meanRTLocal | Mean correct latency (in ms) of all local test trials (block.local only) |
| accShift | Proportion correct of all mixed, shift trials (block.mixed only) |
| meanRTShift | Mean correct latency (in ms) of all mixed, shift trials (block.mixed only) |
| accNonShift | Proportion correct of all mixed, nonshift trials (block.mixed only) |
| meanRTNonShift | Mean correct latency (in ms) of all mixed, nonshift trials (block.mixed only) |
| shiftCost | Estimates the shift cost by subtracting the mean correct latency on shift trials from those of nonshift trials |
File Name: globallocaltask_children_mi_raw*.iqdat
| Name | Description |
|---|---|
| build | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| date | Date the session was run |
| time | Time the session was run |
| subject | Participant ID |
| group | Group number |
| session | Session number |
| blockCode | Name of the current block |
| blockNum | Number of the current block |
| trialCode | Name of the current trial |
| trialNum | Number of the current trial |
| countTrials | Counts overall test trials (starttrial excluded from count) |
| task | Stores the task from the current task: "global" vs. "local" |
| prevTask | Stores the task from the previous task: "global" vs. "local" |
| globalForm | The global form of the current stim: "square" vs. "circle" |
| localForm | The local form of the current stim: "square" vs. "circle" |
| selectedStim | The itemnumber of the currently selected stimulus |
| stimulusItem | The selected image |
| response | The participant's response |
| responseCategory | "circle" vs. "square" (selected shape) |
| correctResponse | The correct response for the current task: "square" vs. "circle" |
| correct | Accuracy of response: 1 = correct response; 0 = otherwise |
| latency | The response latency (in ms); measured from: onset of stim |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| taskReminderDuration | Duration of the reminder that reminds participants what to pay attention to for the global/local block | 2000ms |
| feedbackDuration | Duration (in ms) of feedback smiley | 500ms |
| iti | Intertrial interval (in ms) | 500ms |
| readyDuration | Duration (in ms) of the 'get ready' trial | 5000ms |
| stimSize | Sizing of the stims proportional to the canvas height | 50% |