Stimulus Presentation in Labvanced

In experiments, a stimulus is anything you show or play to a participant—such as text, images, videos, sounds, or even interactive tasks. Stimulus presentation simply means how and when these elements are displayed during your study.

In Labvanced, stimulus presentation is controlled visually, so you don’t need advanced programming skills to get started.

i.) Introduction - Understanding the Basics

Think of your experiment as a sequence of “screens” (called frames in Labvanced). Each frame contains the stimuli you want participants to see.

For example, in the instance of instruction-based tasks:

  1. Welcome screen (text)
  2. Instruction screen (text + image)

Or, in the instance of experimental tasks:

  1. Trial screen (image stimulus + response buttons)
  2. Feedback screen

Labvanced lets you design and control this flow step by step.

Step 1: Adding a Frame

A frame is like a slide in a presentation. The default frame in Labvanced that appears is a Canvas Frame.

  • Go to the Task Editor
  • Under the TRIAL TIMELINE section, click either + Canvas or + Page
  • Give it a meaningful name (e.g., “Trial 1” or “Instructions”)

Each frame can be used to contain / present your stimuli.

Canvas Frame vs. Page Frame

In Labvanced, the choice between canvas frames and page frames depends on the type of task you are designing. Page Frames are used for more structured, form-like screens such as instructions or questionnaires, where elements are arranged in a simple, vertical layout and precise positioning is not critical. In contrast, Canvas Frames provide full control over the placement and timing of elements, allowing stimuli to be positioned anywhere on the screen and presented with high temporal precision. Because of this, Canvas Frames are typically preferred for experiments that require accurate and dynamic stimulus presentation and response measurements, while Page Frames are better suited for more static content and user input.

Learn more.

Step 2: Adding Stimuli to a Frame

Inside a frame, you can add different types of elements / Objects, such as:

  • Text → instructions or questions
  • Image → pictures or visual stimuli
  • Video → clips or animations
  • Audio → sounds or spoken words
  • Buttons / Input fields → participant responses

To add one:

  • Click on the particular Object from the vertical menu
  • Choose the type (e.g., Text or Image)
  • It will be added to the editor automatically, then you can drag & drop it to the position you need and further user the Object Properties panel to further control its presentation (eg. X- and Y- coordinate position)

Step 3: Controlling When Stimuli Appear (Overview)

Stimulus timing is a key part of experiments.

In Labvanced, you control this using events and timing options:

Option A: Simple Timing

  • Select a frame
  • Set a duration (e.g., 2000 ms = 2 seconds)
  • The stimulus will appear for that amount of time

Option B: Event-Based Timing

You can make things happen based on events:

  • Show stimulus after a delay
  • Hide stimulus after a response
  • Move to next frame when a button is clicked

Example:

  • Show image → wait for response → go to next frame

ii.) Expanding your Trial Structure (Repeating Stimuli)

The vast majority experiments repeat stimuli multiple times.

Labvanced uses trials:

  • Utilize the Trial System
  • Each loop iteration presents a new stimulus

You can:

  • Randomize order
  • Load stimuli from a table / data frame (e.g., different images per trial)

Step 5: Using Variables to Control Stimuli

Variables allow you to change what is shown dynamically.

Example:

  • Variable “image_file” contains file names
  • Each trial loads a different image

This is useful for:

  • Personalized stimuli
  • Condition-based presentation
  • Custom randomization (ie. beyond the options already offered)

Step 6: Collecting Responses

Stimulus presentation is usually paired with responses.

You can:

  • Record button clicks
  • Capture keyboard input
  • Measure reaction time

Labvanced automatically logs:

  • What was shown
  • When it was shown
  • How the participant responded

Learn more.

Example: A Simple Reaction Task

Here’s a basic experiment flow:

  1. Fixation cross (“+”) appears for 500 ms
  2. Image appears
  3. Participant presses a key
  4. Next trial starts

In Labvanced:

  • Frame 1: Fixation (timed)
  • Frame 2: Image (wait for response)
  • Loop: Repeat for multiple trials

Tips for Beginners

  • Start simple: build one trial before scaling up
  • Name frames and variables clearly
  • Use preview mode frequently
  • Test timing carefully (especially for reaction-time studies)

Summary

Stimulus presentation in Labvanced is built around:

  • Frames → where stimuli are shown
  • Objects → what is shown (text, images, etc.)
  • Timing & events → when things happen
  • Trial System and/or Data Frames → repetition and structure

Once you understand these principles building blocks, you can create a wide variety of experiments—from simple surveys to complex cognitive tasks.