Drawing Task

Version: v1 (current)

A free-form drawing task for assessing visuospatial ability, motor control, and creative expression.

Overview

The Drawing task allows participants to create drawings using a digital canvas (mouse, touchscreen, or stylus). It can be used for free drawing, tracing, or copying reference images. Drawing tasks are used in neuropsychological assessment (e.g., clock drawing test, Rey-Osterrieth Complex Figure), developmental research, and studies of motor control and spatial cognition.

Digital drawing provides rich data including stroke trajectories, timing, pressure (if available), and spatial organization. The task can range from simple shapes to complex figures depending on assessment goals.

Why Researchers Use This Task

1. Clock Drawing Test: Assess visuospatial function and executive function
2. Copy Tasks: Measure visuomotor reproduction accuracy
3. Free Drawing: Creative expression and developmental assessment
4. Trail Making: Connect numbered or lettered nodes in order
5. Neuropsychological Screening: Sensitive to cognitive decline and spatial deficits

Where to Configure

Study Form → Tasks → Drawing → Configure.

Configuration Parameters

Parameter	Type	Default	Description
Main Instructions	rich text	''	Instructions shown to the participant
Hint Instructions	rich text	''	Optional hint / secondary instructions
Trials Instructions	rich text	(empty)	Instructions shown above the drawing canvas
Reference Image	uploaded image	(none)	Optional image displayed above the canvas (e.g. a figure to copy). Uploaded in the config; stored as drawing_reference_url

Unlike other tasks, where trials instructions appear on a pre-trial page, the Trials Instructions here are rendered as a persistent caption above the drawing canvas during the drawing period.

The drawing canvas dimensions are fixed in the runtime (600 × 400 px, scaled to fit the viewport) and are not configurable. There is no time limit, brush/color/eraser tool selection, or stroke-data setting in this task's configuration.

Participant Flow

1. The participant sees a blank canvas. If a reference image was uploaded, it is displayed above the canvas.
2. The participant draws on the canvas using mouse, touchscreen, or stylus (pointer) input.
3. The participant can press Clear to erase the canvas and start over. Each non-blank clear captures a snapshot of the drawing at that point.
4. The participant presses the Next button to submit their final drawing and advance.

Data Output

Markers and Responses

The task records markers and responses with high-resolution timestamps (ts, hr). Each marker has the shape { "type", "ts", "hr", "data": { ... } }.

Markers

Marker	Data fields	Description
stimulus_shown	reference_url	Canvas shown (reference image URL, or null if none)
stroke_start	stroke_index	Pointer-down begins a new stroke (1-based index)
stroke_end	stroke_index	Pointer-up ends the current stroke
canvas_cleared	clear_index	Clear button pressed (1-based index)

Response Data

Each response row is written flat with ts and hr appended. A per-clear snapshot row carries clear_index, is_final: false, and (when a snapshot was captured) artifact_filename, type, size. The terminal submit row carries clear_index: null, is_final: true, responded, and (when a drawing was exported) artifact_filename, type, size. For example, the terminal row:

{
  "clear_index": null,
  "is_final": true,
  "responded": true,
  "artifact_filename": "drawing_2.png",
  "type": "image/png",
  "size": 52310
}

Drawing Artifact

The participant's drawing is exported as a PNG image. The terminal submission is saved as drawing_<taskIndex>.png. Each non-blank Clear also captures the canvas as drawing_<taskIndex>_<clearIndex>.png before erasing. These images can be scored manually. The task does not store vector stroke paths or per-point coordinates; only the rendered PNG plus stroke-start/stroke-end timing markers are captured.

Design Recommendations

• Reference Images: For copy tasks, upload a reference image; it is displayed above the canvas so participants can see both simultaneously.
• Instructions: Provide clear instructions about what to draw and whether the drawing should be as accurate as possible or free-form.
• Input Devices: Test with the same input device participants will use; mouse drawing differs substantially from stylus or touchscreen drawing.

Common Issues and Solutions

Issue	Solution
Drawing looks jagged	Ensure participants use slow, deliberate strokes; consider using a stylus for finer control
Reference image not visible	Re-upload the reference image in the task configuration and confirm the preview appears
Participants unsure what to draw	Provide clear instructions before the task; include a practice trial

References

• Freedman, M., Leach, L., Kaplan, E., Winocur, G., Shulman, K. I., & Delis, D. C. (1994). Clock Drawing: A Neuropsychological Analysis. Oxford University Press.
• Osterrieth, P. A. (1944). Le test de copie d'une figure complexe. Archives de Psychologie, 30, 206-356.

See Also

• Copy of Cube - Specific 3D drawing assessment
• Fitts' Law - Motor targeting precision