What is Aphantasia?
Aphantasia is a condition where otherwise healthy individuals completely lack the ability to visualize mental images. While most people can easily imagine a red apple or recall visual memories, those with aphantasia experience no visual imagery in their "mind's eye."
Visualizing thoughts, past memories, or images of the future is ubiquitous in our daily lives. However, this visualization experience is entirely unknown for approximately 1-3% of the population who have aphantasia. Testing for this condition has evolved from subjective questionnaires to more objective methods like the binocular rivalry aphantasia test. Current Aphantasia Assessment Methods
The Vividness of Visual Imagery Quiz (VVIQ)
To determine whether someone has aphantasia, many researchers conduct an initial evaluation using the Vividness of Visual Imagery Quiz (VVIQ). This assessment asks you to rate the vividness of different scenarios to test the strength of your visual imagery. The VVIQ is a proven psychometric tool for measuring individual differences in visual imagination and is considered a reliable self-assessment for identifying potential aphantasia. However, it relies on subjective reporting, which led scientists to seek more objective measurement methods.
The Need for Objective Measurement
Until recently, it was unclear to scientists whether people with aphantasia: Could not imagine visually at all, or
- Had images in their minds but were simply unaware of them
To objectively address this question, a team of researchers from UNSW led by Dr. Joel Pearson conducted a study using binocular rivalry and a technique called perceptual priming. These studies are typically conducted in controlled laboratory environments with specialized equipment to ensure accurate results.
What is Binocular Rivalry Testing?
Important Note:
Professional binocular rivalry testing is typically conducted in controlled laboratory environments with specialized equipment, standardized protocols, and trained researchers. The home version described in this article is a simplified adaptation that can provide insights but will not have the same accuracy as laboratory testing.
Understanding Visual Perception
When light enters our eyes, it sends information to our brains about the world around us. The brain collects visual data from both eyes and combines this information to show us one unified image. However, the brain can get confused when both eyes receive completely different sensory information.
How Binocular Rivalry Works
Binocular rivalry is a phenomenon of visual perception where perception alternates between different images presented to each eye. Instead of overlapping conflicting images, only one image dominates, and that's what you consciously see.
In the red-blue superimposed images used for aphantasia testing, the red image is filtered to one eye while the blue image is filtered to the other eye through the colored glasses. For example, when viewing a superimposed red zebra and blue kangaroo image through red-blue glasses, your left eye might see only the red zebra while your right eye sees only the blue kangaroo. Your brain will "choose" to show you either the red zebra or the blue kangaroo, but not both simultaneously.
Test Image 1 - Kangaroo (blue) and Zebra (red) superimposed. Record which animal appears more dominant. Illustration by Helmo. Rabbit-Leopard: Brad Wilson/Getty Image. Perceptual Priming and Mental Imagery
Here's where it gets interesting: perceptual priming occurs when visualizing a specific image or color in your mind makes you more likely to see that image during binocular rivalry.
- People without aphantasia: Can visualize colors mentally, which primes their brain to see that color more often
- People with aphantasia: Cannot visualize colors mentally, so no priming occurs, and they see both images equally often
How to Test for Aphantasia at Home
Important Disclaimer:
This is a simplified home version of laboratory binocular rivalry testing. Professional testing in controlled environments with specialized equipment and trained researchers provides more accurate and reliable results. This home test should be considered exploratory and not diagnostic.
What You'll Need
- (old-school theater glasses work perfectly)
- A computer or mobile device
- A stable surface to rest your chin on (stack of books works well)
- Paper and pen to record results
Step-by-Step Binocular Rivalry Experiment
Phase 1: Baseline Testing
- Record your baseline results
Test Image 2 - Rabbit (blue) and Leopard (red) superimposed. Note which color dominates your perception. Illustration by Helmo. Rabbit-Leopard: Brad Wilson/Getty Images. Phase 2: Priming Test
- Repeat the viewing test (up to 10 times)
- Record your priming results
Phase 3: Results Analysis
Compare your results from Phase 1 and Phase 2: Did you see red more frequently in Phase 2?
- Was there a significant difference between the two phases?
- Record the percentage increase (if any) in red dominance
Test Image 3 - Butterfly (blue) and Spider (red) superimposed. Record your dominant perception. Illustration by Helmo. Tarantula: Davies and Starr/Getty Images. Results Tracking Template
PhaseRed DominanceBlue DominanceUnclearNotesBaseline__/ 10__/ 10__/ 10Priming__/ 10__/ 10__/ 10Differrence+/-__+/-__+/-__
Interpreting Your Results
Likely Non-Aphantasic Results
- Significant increase in red dominance during priming phase
- 6-8 out of 10 times seeing red when priming for red
- Clear difference between baseline and priming phases
Potential Aphantasia Indicators
- Little to no change between baseline and priming phases
- Difficulty or inability to visualize red during priming
- Randomor equal distribution of red/blue dominance in both phases
Important Considerations
This home test provides insight into your mental imagery abilities but has limitations:
Laboratory vs. Home Testing
- Professional labs use calibrated displays, controlled lighting, precise timing, and standardized protocols
- Home testing variables include screen quality, lighting conditions, glasses quality, and individual setup differences
- Research standards typically require multiple sessions with dozens of trials for reliable results
General Limitations
- Not a diagnostic tool: Only a qualified professional can diagnose aphantasia
- Requires repetition: Multiple trials increase accuracy
- Individual variation: Results may vary due to factors like fatigue or concentration
Are There Other Objective Tests For Aphantasia?
Researchers use several objective measures, typically in laboratory settings.
Laboratory-Based Tests
- fMRI studies measuring brain activity during imagery tasks in controlled scanner environments
- Pupillometry measuring pupil responses to imagined bright/dark scenes using specialized eye-tracking equipment
- EEG studies recording electrical brain activity during mental imagery tasks
- Reaction time studies measuring responses to imagery-based tasks with precise timing equipment
Clinical and Research Assessments
- Standardized drawing tasks comparing memory-based drawings under controlled conditions
- Multi-session binocular rivalry testing with calibrated equipment and statistical analysis
- Comprehensive imagery questionnaires administered by trained researchers
- Behavioral paradigms testing imagery across different sensory modalities
What Should I Do If I Think I Have Aphantasia?
If you think you might have aphantasia, consider: Taking the
- Contrasting your experience with how others and sharing about aphantasia
- Consulting with an about your experience
- Connecting with the for peer support
- Remember: Aphantasia is a variation, not a disorder requiring treatment
This article is for educational purposes only and does not constitute medical advice. If you have concerns about your mental imagery abilities, consult with a qualified professional. 
