Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 25, 2013
Last Modified: January 11, 2025 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script runs a simple visual reaction time task.
4 minutes
The participant gets presented a fixation cross that is followed after variable time intervals by a visual target stimulus (here: circle). The participant's task is to press the spacebar as soon as the target stimulus appears on the screen. Latency, mean latency, and latency standard deviation are recorded in the data file.
• By default, the script runs 2 blocks of 20 trials each
• By default, the fixation cross as well as the target stimuli appear in the center of the screen. Changes can be made under
section Editable Parameter, including changing the script so that the target stimuli appear randomly in one of 9 screen positions.
• By default, the time intervals are randomly chosen from 2000ms, 3000ms, 4000ms, 5000ms, 6000ms, 7000ms, 8000ms
• By default, the fixation cross is black.
• By default, the color of the circle is red.
• By default, the color of the screen background is white.
see section Editable Instructions
File Name: srtvisual_summary*.iqdat
| Name | Description |
|---|---|
| inquisit.version | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| computer.touch | 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities |
| computer.hasKeyboard | 0 = no external keyboard detected; 1 = external keyboard detected |
| 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 |
| trial.srtt.totalMeanLatency | The mean latency across all trials.SRTT (in ms) |
| trial.srtt.totalMedianLatency | The median latency across all trials.SRTT (in ms) |
| trial.srtt.totalMinLatency | The fastest response across all trials SRTT (in ms) |
| trial.srtt.totalMaxLatency | The slowest response across all trials SRTT (in ms) |
| trial.srtt.totalSDLatency | The the standard deviation of the latency responses across all trials SRTT |
| trial.srtt.totalVarLatency | The variance of the latency responses across all trials SRTT |
File Name: srtvisual_raw*.iqdat
| Name | Description |
|---|---|
| build | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| computer.touch | 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities |
| computer.hasKeyboard | 0 = no external keyboard detected; 1 = external keyboard detected |
| date | Date the session was run |
| time | Time the session was run |
| subject | Participant ID |
| group | Group number |
| session | Session number |
| blockcode | The name the current block (built-in Inquisit variable) |
| blocknum | The number of the current block (built-in Inquisit variable) |
| trialcode | The name of the currently recorded trial (built-in Inquisit variable) |
| trialnum | The number of the currently recorded trial (built-in Inquisit variable) trialnum is a built-in Inquisit variable; it counts all trials run even those that do not store data to the data file. |
| stimulusItem | The first presented stimulus (=fixation cross) |
| focusx | The x-coordinate of the fixation cross |
| focusy | The y-coordinate of the fixation cross |
| focuscolor | The color of the fixation cross |
| focussize | The size of the fixation cross |
| stimulusItem | The second presented stimulus (=target) |
| targetcolor | The current color of the target circle |
| targetsize | The current color of the target circle |
| targetx | The x-coordinate of the target circle |
| targety | The y-coordinate of the target circle |
| fixed | 0= fixed position of target; 1 = random position of target |
| maxtrialnumber | The number of trials in a block |
| trials.srtt.count | Counts the SRTT trials run in a given block |
| stimInterval | The current stimulus interval |
| latency | The latency of the response (in ms) |
| trial.srtt.meanLatency | The mean latency in the current block (in ms) |
| trial.srtt.medianLatency | The median latency in the current block (in ms) |
| trial.srtt.minLatency | The fastest response in the current block (in ms) |
| trial.srtt.maxLatency | The slowest response in the current block (in ms) |
| trial.srtt.sdLatency | The standard deviation of the latency responses in the current block |
| trial.srtt.varLatency | The variance of the latency responses in the current block |
| trial.srtt.totalMeanLatency | The mean latency across all trials.SRTT (in ms) |
| trial.srtt.totalMedianLatency | The median latency across all trials.SRTT (in ms) |
| trial.srtt.totalMinLatency | The fastest response across all trials SRTT (in ms) |
| trial.srtt.totalMaxLatency | The slowest response across all trials SRTT (in ms) |
| trial.srtt.totalSDLatency | The the standard deviation of the latency responses across all trials SRTT |
| trial.srtt.totalVarLatency | The variance of the latency responses across all trials SRTT |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
Design |
||
| maxTrialNumber | Sets the number of trials that should be run in a block | 20 |
| fixed | Determines whether to use the fixed coordinates for the target stimulus (= 0) or to select randomly from 9 different screen positions (=1) | 0 |
Colors |
||
| screenColor | Sets the background color of the screen | white |
| targetColor | Sets the color of the circle; the default is red | red |
| focusColor | Sets the color of the focus stimulus; the default is black | black |
Sizes |
||
| targetSize | Sets the size of the circle; relative to the vertical canvas | 10% |
| focusSize | Sets the size of the focus stimulus; relative to the vertical canvas | 10% |
Coordinates |
||
| targetx | Sets the x-coordinate of the target circle ; the default is the center | 50% |
| targety | Sets the y-coordinate of the target circle , the default is the center | 50% |
| focusx | Sets the x-coordinate of the focus stimulus; the default is the center | 50% |
| focusy | Sets the y-coordinate of the focus stimulus; the default is the center | 50% |