Script Author: David Nitz (dave@millisecond.com), Millisecond, Millisecond
Last Modified: January 15, 2023 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements the 'Game of Dice Task' (GDT), a test of risky gambling decisions, with and without feedback (optional). The script was customized for the ABCD Research Consortium and is generously shared via the Millisecond Test Library. This script has been optimized for smartphones (remote testing). A version for tablets (in person testing) is also available.
The implemented procedure is based on:
(with feedback): Brand, M., Fujiwara, E., Borsutzky, S., Kalbe, E., Kessler, J., & Markowitsch, H.J. (2005). Decision-making deficits of Korsakoff patients in a new gambling task with explicit rules - associations with executive functions. Neuropsychology, 19, 267–277.
And
(without feedback) Brand, M. (2008). Does the feedback from previous trials influence current decisions? A study on the role of feedback processing in making decisions under explicit risk conditions. Journal of Neuropsychology, 2, 431-443.
By default the script plays the version WITH feedback. To play the version WITHOUT feedback, go to Editable Task Parameters -> parameters.GDTversion and change to parameters.GDTversion = 2.
5 minutes
A dice is being rolled and participants have to bet on the outcome. They have the choice between 4 different kinds of bets: - a single bet (betting on a specific dice face: earns the most money if correct, but loses the most if incorrect (very risky bet) - a dual bet (betting on two possible dice faces: if either one of them is rolled, it's a win. earns/loses slightly less than single bet (risky bet) - a triple bet (betting on three possible dice faces: earns/loses less than dual bet (safe bet) - a quadruple bet (betting on four possible dice faces: ears/loses the least (safest bet) Participants can quit at any point before the default rounds (18) are played.
• one-trial for practice (does not count towards summary statistics)
• by default max. 18 rounds get played (set under section Editable Parameters)
• participant can quit at any point
• the faces are selected randomly without replacement from list.rolldice
• by default, participant get feedback of the dice throw and updating of account information
Revised instructions, visuals and other procedural details thanks to the helpful and generous input
from the original authors.
verbal instructions made available by the ABCD Research Consortium
File Name: abcdgameofdicetask_smartphone_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 |
| gdtVersion | 1 = original version with feedback (default); 2 = version without feedback |
| accountBalance | Amount participant owns at the end |
| single | Counts how many times participant has bet on 1 specific dice face |
| double | Counts how many times participant has bet on 2 possible dice faces |
| triple | Counts how many times participant has bet on 3 possible dice faces |
| quadruple | Counts how many times participant has bet on 4 possible dice faces |
| safe | Counts how many times participants selected a safe bet (bets on 3 or 4 dice faces) |
| risky | Counts how many times participants selected a risky bet (bets on 1 or 2 dice faces) |
| netScore | Reflects the number of safe (bets on 3 or 4 numbers) vs. risky (bets on 1 or 2 numbers) choices. It is computed as number of safe bets minus number of risky bets. |
| wins | Adds the number of winning bets |
| losses | Adds the number of losing bets |
File Name: abcdgameofdicetask_smartphone_raw*.iqdat
| Name | Description |
|---|---|
| build | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| date, time, subject, group, session | Date and time script was run with the current subject/groupnumber/session number |
| gdtVersion | 1 = original version with feedback (default); 2 = version without feedback |
| blockCode | Name of the current block |
| blockNum | Number of the current block |
| phase | "practice" vs. "test" |
| currentRound | Stores the current round number (resets after practice) |
| trialCode | Name of the current trial |
| trialNum | Number of the current trial |
| latency | The response latency (in ms) |
| chosen | The selected dice faces participants is betting on (example: "1", "12", "123", "1234") |
| throw | The dice face thrown |
| row | Reflects participant's betting choice For "singles" ("1", "2", etc.) values.row = 1 For "doubles" ("12", "34", etc.) values.row = 2 For "triples" ("123", "456") values.row =3 For "quadruples" ("1234", etc.) values.row = 4 |
| currentbet | The amount of money currently bet on values.chosen |
| gain | Amount of money won or lost in the current round (e.g. -500) |
| accountBalance | Amount participant owns |
| single | Counts how many times participant has bet on 1 specific dice face |
| double | Counts how many times participant has bet on 2 possible dice faces |
| triple | Counts how many times participant has bet on 3 possible dice faces |
| quadruple | Counts how many times participant has bet on 4 possible dice faces |
| safe | Counts how many times participants selected a safe bet (bets on 3 or 4 dice faces) |
| risky | Counts how many times participants selected a risky bet (bets on 1 or 2 dice faces) |
| netScore | Reflects the number of safe (bets on 3 or 4 numbers) vs. risky (bets on 1 or 2 numbers) choices. It is computed as number of safe bets minus number of risky bets. |
| wins | Adds the number of winning bets |
| losses | Adds the number of losing bets |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| gdtVersion | 1 = original version with feedback (default) 2 = version without feedback adjust instructions accordingly under section Editable Instructions | |
| nRoundsGdt | Number of rounds in feedback version (must be a multiple of 6); default is 18 | |
| nRoundsGdtNf | Number of rounds in no-feedback version (must be a multiple of 6); default is 18 IMPORTANT: When in- or decreasing the number of rounds in either version, adjust the number of items in list.rolldice accordingly. | |
| accountBalanceStart | Amount of points / Money at Task Onset | |
| currency | Exchange "$" with "€", "£", "¥", etc. | |
| gainSingle | Amount to be won/lost when betting on a single number (e.g. "3") | |
| gainDouble | Amount to be won/lost when betting on a combination of two numbers (e.g. "5 or 6") | |
| gainTriple | Amount to be won/lost when betting on a combination of three numbers (e.g. "1 or 2 or 3") | |
| gainQuadruple | Amount to be won/lost when betting on a combination of four numbers (e.g. "2 or 3 or 4 or 5") | |
| showQuitButton | True: the quit button is visibly presented during each trial false: the quit button is invisible | false |
| scriptLastUpdate | Should store the date of the last change made to the script |