Class 4 — Custom Code Components

Write your own logic for the first time using a PsychoPy Code Component — dictionary-based accuracy scoring and dynamic feedback — plus the course-wide minimum-observations design constraint every final project must satisfy.

Class 3 was about reading and lightly editing Builder’s generated Python. Today you write your own logic using a Code Component, the Builder-safe way to add custom Python that survives Builder regenerating the script. You’ll build a dictionary-based accuracy check with feedback text, then program a minimal version of it into your own HW1 task. Along the way, you’ll name this course’s minimum-observations design constraint explicitly — already satisfied by the original Stroop task’s conditions file and reps setting, not by anything you build today.

Reading due: Think Python ch. 9–10 · Due today: —

What you’ll be able to do

1. Build and index a Python dictionary, count occurrences of a value in a list, and compute the mean of a list of numbers, reinforced through a Colab warm-up.
2. Explain what a PsychoPy Code Component is, where its six code tabs (Before Experiment / Begin Experiment / Begin Routine / Each Frame / End Routine / End Experiment) run relative to a routine’s lifecycle, and why it’s the Builder-safe alternative to Class 3’s direct script edits.
3. Add a code component to the original Stroop task that scores accuracy and/or produces dynamic feedback, using a dictionary lookup rather than hard-coded per-trial logic, and that saves each condition’s proportion correct to the data file.
4. Explain the course-wide minimum-observations design constraint — every final project needs at least 18 observations per level for its manipulated factor — and recognize that for the original Stroop task it’s already guaranteed by the conditions file and reps setting from Class 2, not by any runtime check built today.
5. Connect today’s dictionary-based scoring back to Class 3’s discovery of the correct-answer conditional in the generated code, and recognize that a code component is where you now write the kind of logic Builder was writing for you automatically.