Text Stimuli
Version: v1 (current)
Display text content (words, sentences, paragraphs, stories) to participants during research studies.
Overview
The Text stimuli task presents standardized text passages to participants for reading, comprehension, or priming purposes. Content is authored with a rich text editor supporting bold, lists, headings, links, and embedded images or video. The content is saved as HTML and rendered as-is during the task.
Common research uses include:
- Memory encoding: Read a story, then answer questions about it later
- Priming: Show word lists or priming passages before another task
- Reading comprehension: Present passages for comprehension testing
- Instruction displays: Task-specific detailed instructions beyond the standard instructions task
Where to Configure
Study form → Tasks → Stimuli tasks → Text → Configure.
Configuration Parameters
Text-Specific Parameters
| Parameter | Type | Default | Description |
|---|---|---|---|
| Text Content | string (HTML) | '' | Rich text content authored via the editor |
| Font Size (px) | number | 24 | Font size for the displayed text |
| Text Align | string | 'center' | Text alignment ('left', 'center', 'justify') |
Common Stimuli Parameters
| Parameter | Type | Default | Description |
|---|---|---|---|
| Display Duration (ms) | number | 0 | Duration to show stimulus (0 = until participant advances) |
| Auto Advance | boolean | false | Auto-advance after duration (requires Display Duration > 0) |
| Button Text | string | 'Continue' | Text for advancement button |
| Show Timer | boolean | false | Display countdown timer |
| Background Color (hex) | string | 'FFFFFF' | Background color |
Participant Flow
- The participant sees the text content displayed on screen.
- If self-paced (Display Duration = 0), the participant reads and clicks the button to continue.
- If timed, the text is shown for the specified duration and may auto-advance.
Design Recommendations
- Font size: Use 18-24 px for body text to ensure readability across screen sizes.
- Contrast: Ensure high contrast between text and background color.
- Length: Keep passages concise and legible; pretest reading time for your target audience.
- Encoding studies: Use fixed durations (e.g., 5 s per paragraph) for consistency across participants.
- Reading tasks: Self-paced is preferred so participants control when they finish.
Common Issues and Solutions
| Issue | Solution |
|---|---|
| Participants skip without reading | Set a minimum Display Duration or use the Instructions task with scroll-to-bottom requirement |
| Text too small on some screens | Use a font size of at least 18 px; test on target devices |
| HTML formatting not rendering | Ensure valid HTML in the rich text editor; test rendering in preview mode |
Data Output
Markers and Responses
Markers (stimulus_shown):
{
"type": "stimulus_shown",
"ts": "2024-01-01T00:00:01.000Z",
"hr": 1234.56,
"data": {
"type": "text",
"text": "<p>Read the following passage carefully...</p>"
}
}
Markers (response_recorded):
{
"type": "response_recorded",
"ts": "2024-01-01T00:00:08.000Z",
"hr": 8234.56
}
Response Data:
{
"type": "text"
}
Summary Artifact
None. The text stimulus task does not generate a summary artifact.
References
References depend on specific stimuli used. For general text presentation in research:
- Foroni, F., & Semin, G. R. (2009). Language that puts you in touch with your bodily feelings: The multimodal responsiveness of affective expressions. Psychological Science, 20(8), 974-980.
Verbal stimuli databases:
- ANEW: Affective Norms for English Words
- MRC: MRC Psycholinguistic Database (word properties)
- SUBTLEX: Word frequencies from subtitles