Button
Category:
AddIn:
Scope:
Code Snippets:
Supports Material List:
Status Screen Widgets:
License:
Input Registration
Base Elements
Local
Triggered
no
no
Standard EventIDE license
In this article:
Introduction
The Button element monitors participant responses from standard input devices supported by Windows, including keyboards, computer mouses, gamepads, and joysticks. It provides accurate event timing information and is commonly used for response collection, reaction time measurement, behavioral task control, and participant interaction during experiments.
The element can detect presses, releases, or sustained button states, making it suitable for a wide range of experimental paradigms.
Description
The Button element continuously monitors a selected button on a chosen input device and records its activity relative to the onset of the parent event. The element automatically stores the exact triggering time, identifies which button was pressed, and exposes runtime properties that can be used in Flow Routes, Conditions, and Code Snippets.
Multiple Button elements can be used simultaneously to monitor different response keys or different input devices.
Typical applications include:
Reaction-time experiments
Go/No-Go paradigms
Two-alternative forced-choice (2AFC) tasks
Cognitive and behavioral testing
Motor response measurements
Gamepad-based experiments
Custom response box integration through keyboard emulation
Key Features
Supports keyboards, computer mouses, gamepads, and joysticks
Records precise button trigger times
Measures reaction times relative to event onset
Monitors specific buttons or any button on a device
Supports press, release, and continuous-state monitoring
Can trigger Flow Routes and event transitions
Exposes runtime status for Code Snippets and Conditions
Supports multiple simultaneous response devices
Properties
Name | Description | Type | |
Settings | |||
Device Type | Defines a type of the input button device | Design | Int32 |
Selected Device | Defines the selected input button device. If the system device is selected, button actions are recorded from all listed devices | Design | Int32 |
Triggering Mode | Defines the triggering mode for the button. The First Press Only mode is recommended for response time measurements | Design | enButt.. |
Monitored Button | Defines the button monitored by the element. If Any Button is selected, the element monitors all buttons on the selected device. The actual pressed button can then be identified using the Triggered Button property | Design | Int32 |
Runtime Status | |||
Triggering Time | Returns the local event time (ms) of the last button trigger. This value can be used as an accurate response time measure | Status | clTime |
Is Triggered | Indicates whether a button has been triggered at least once since the onset of the parent event. Commonly used to control flow routes and event transitions | General | Boolean |
Triggered Button | Returns the system name of the triggered button. Keyboard keys are reported as capital letters, while mouse and gamepad buttons are reported using names such as "Button 1" | Status | String |
Is Down | Indicates whether the monitored button is currently in the down state | General | Boolean |
Control | |||
Is Enabled | If set to false the element is completely omitted when the experiment is run | Design | Boolean |
Title | Title of the element | Design | String |
Practical Use
Technique 1: Recording Participant Responses and Reaction Times
Add a Button element to the stimulus event.
Select the desired input device in Selected Device property in the Properties Panel.
Choose the response key using Monitored Button.
Set Triggering Mode to First Press Only for reaction-time measurements.
Present the stimulus.
Create a Flow Route that advances when Is Triggered = True.
Read Triggering Time to obtain the participant's reaction time.
Example
A participant views a visual stimulus and presses the spacebar as soon as it appears. The Button element records the response time and signals the experiment to continue to the next event.
Technique 2: Two-Alternative Forced Choice (2AFC) Task
Add two Button elements to the response event.
Configure one element to monitor the left response key (e.g., A).
Configure the second element to monitor the right response key (e.g., L).
Use Flow Routes or Code Snippets to determine which button was pressed.
Store response accuracy and reaction time in user variables.
Example
Participants classify faces as male or female using two keyboard buttons. The selected button determines the recorded response category.
Technique 3: Monitoring Any Button Press
When the exact response button is unknown in advance, the Button element can monitor all buttons on a device.
Add a Button element.
Select the desired device in the Properties Panel.
Set Monitored Button property to Any Button.
When a response occurs, read Triggered Button property via a proxy variable to determine which button was pressed.
Example
A gamepad-based task allows participants to use any available button. The Button element records both the response time and the specific button identity.
Technique 4: Continuous Button-State Monitoring
The Button element can be used to detect whether a button is currently held down.
Configure the monitored button.
Read the Is Down property during runtime via a proxy variable.
Use Route Conditions or Code Snippets to react to sustained button presses.
Example
In a force-maintenance task, participants must hold a button continuously during stimulus presentation. The experiment terminates the trial if the button is released.
Notes
First Press Only triggering mode is generally recommended for reaction-time measurements because it prevents repeated triggers while a key is held down.
The Triggering Time property provides the most accurate response-time measure and should be preferred over manually calculated timestamps.
When monitoring Any Button, use the Triggered Button property to identify the participant's response.
Multiple Button elements can be combined to create multi-choice response interfaces.
Button elements are frequently used together with Condition, Flow Route, and Code Snippet elements for experiment control.
If a dedicated response device emulates keyboard input, it can usually be used directly with the Button element without additional configuration.