Multiple stims on trial but presented sequentially

[mt_FF]

Hello! Here is the solution we came up with.

First, create trial templates for stimuli and responses only. To do this, you can leave "responses" and "stimuli" parameters blank, respectively. You should create multiple stimulus templates as some trials present 1 video and others present 2, for example, in your design. Here's what those templates would look like.

{
  // A separate template with only the desired response
  "Response_Template": {
    "type": "basic",
    "stimuli": [],
    "responses": ["rate"]
  },
  // A separate template for the string of only 1 video
  "Stimulus_Template_1_video": {
    "type": "basic",
    "stimuli": ["example_video_stimulus"],
    "responses": [],
    "auto_advance": true
  },

...  // Make separate templates for the string of 2 videos, 3 videos, and so on

Now, you have two options as to how to configure your procedure.

Option 1: Create a single block with manual placement of response trial template, like the following:

"ALL_video_presentation_block": {
        "trial_templates": [
          "Stimulus_Template_1_video",
          "Response_Template",
          "Stimulus_Template_2_videos",
          "Response_Template",
          "Stimulus_Template_3_videos",
          "Response_Template"
        ]
      },

Option 2: Create multiple blocks for stimulus templates, and use the response template as end trials for the separate blocks, like the following:

"ONE_video_presentation_block": {
        "trial_templates": ["Stimulus_Template_1_video"],
        "end_trials": ["Response_Template"]
      },
      "TWO_video_presentation_block": {
        "trial_templates": ["Stimulus_Template_2_videos"],
        "end_trials": ["Response_Template"]
      },

... // and so on

You can choose whichever option that works better for your design.

I hope this helps, and please let us know if you have any clarification questions.