Mental Rotation

How it works

This is a careful experiment with visual attention. It is not a diagnosis or an established treatment for OCD, PTSD, or anything else.

Start Mental Rotation

The basic idea

Holding and rotating shapes in mind uses some of the same limited visual working-memory capacity involved in vivid imagery. That can make an image feel less accessible while the task is happening. Some clinical studies also found fewer later trauma-related intrusions, but other large studies did not find a lasting effect.

The strongest evidence is about visual memories after trauma. Direct evidence for OCD-generated images is missing, so Lab treats this as an experiment, not therapy.

What you do

Choose one recurring unwanted visual image and record a starting estimate.
Learn either Rotation Grid or Rotation Choice before bringing the image to mind.
Briefly recognize the image without analyzing or intensifying it.
Spend about 20 active minutes on the rotation task for that one image.
If you want, record one immediate check-in and track unexpected recurrences later.

Why so long? A commonly cited clinical protocol pairs a brief cue for one specific intrusive memory with 20 minutes of gameplay using mental rotation. Other studies have used somewhat different lengths, so 20 minutes should not be treated as a proven perfect dose. It is the closest match to the protocol this version mainly draws from.

The timer pauses when the page is hidden or the task is paused. There is no live therapeutic score.

The two tasks

Rotation Grid asks you to plan how a block should turn and fit before you move it. It is closer to the rotate-and-place behavior used in Tetris-based studies, but it is still Diffrint's own implementation.

Rotation Choice briefly shows a source shape, hides it, then asks how far it must rotate to match a target. It is simpler and also has a no-JavaScript version.

Practice happens first so the image cue is not followed by learning controls. Mirror trials and live accuracy scores are left out because they could shift the task toward checking and performance.

Why the follow-up matters

An immediate change in vividness or distress does not tell you whether the exercise had a lasting effect. The more useful question is whether the image shows up unexpectedly less often during days 1 through 7 and, optionally, days 29 through 35.

The diary is prospective: future dates stay locked until they arrive. It is meant to record spontaneous appearances, not prompt you to test the image.

OCD and safety

For OCD, repeatedly using any exercise to cancel an obsession, obtain certainty, or force anxiety down can become another neutralizing ritual. Mental Rotation is framed as one scheduled experiment, not something to do whenever an image appears. Established OCD care still centers on CBT with exposure and response prevention.

The safety question separates unwanted intrusive images or impulses from current intent. If someone may act on a harmful image or cannot keep people safe, this task is not the right tool for that moment.

Privacy and saving

The task runs in the browser and does not send your session or diary answers to Diffrint. It contains no advertising. Saving is optional and stays on the device. The private image label is kept only in page memory and is excluded from saved sessions and downloads.

Saved timestamps, ratings, task data, and diary counts can still be sensitive. Mental Rotation includes controls to erase its own current and older browser records without removing the shared Lab theme preference.