Chimp Test Explained: Can You Beat a Chimpanzee at Memory?
In a famous 2007 experiment, a young chimpanzee named Ayumu consistently outperformed university students at this exact task. Here's why — and how you compare.
What Is the Chimp Test?
The chimp test is a spatial working memory task in which numbers appear briefly on screen, then vanish after you click the first one. You must then tap the remaining positions in ascending numerical order — entirely from memory. With each successful round, one more number is added.
The test is directly inspired by groundbreaking research conducted at the Primate Research Institute of Kyoto University, where a young chimpanzee named Ayumu repeatedly outperformed adult humans at this exact task — a finding that made international headlines in 2007 and challenged long-held assumptions about human cognitive superiority.
The Famous Ayumu Experiment
In the original study by Sana Inoue and Tetsuro Matsuzawa (published in Current Biology, 2007), chimpanzees were trained to touch numbers 1 through 9 in ascending order on a touchscreen. When the experimenter masked the numbers after the first touch, the chimps — particularly Ayumu — could still correctly identify all remaining positions with remarkable accuracy.
University students, given the same task, performed significantly worse. Even after extended practice, humans rarely matched Ayumu's performance.
Why are chimps better at this?
The leading explanation is eidetic-like photographic memory — the ability to retain a high-fidelity visual snapshot of a scene for a brief window of time. Researchers believe this capacity may have been evolutionarily advantageous for chimpanzees in their natural habitat: rapid assessment of a complex visual scene (which fruit is ripe, where are rivals positioned) requires instant, accurate spatial recall.
Humans, by contrast, evolved to prioritise language and sequential reasoning — cognitive capacities that came at the partial cost of instant visual capture. Our working memory is more flexible and multi-modal, but it's slower and less precise for raw spatial snapshots.
This trade-off is sometimes called the cognitive trade-off hypothesis (Matsuzawa, 2007): humans traded photographic memory for language.
What Does the Chimp Test Measure?
The chimp test isolates a specific and rarely tested cognitive capacity:
Rapid visuospatial encoding: The brief window in which numbers are visible requires you to capture their positions near-simultaneously, rather than reading them sequentially.
Short-term spatial memory: After the numbers vanish, you must retain a mental map of each number's position long enough to act on it.
Inhibitory control: You must suppress the natural tendency to click nearest numbers first or follow visual patterns — and instead follow strict ascending numerical order from memory.
Processing speed under pressure: The numbers vanish immediately after your first click, creating a hard time limit on encoding. Slow initial scanning = missed positions.
Average Chimp Test Scores
The chimp test is rated Hard on BrainRivals — and the scores reflect it. Most players find this the most challenging of all memory tests:
| Performance Level | Numbers Recalled | BrainRivals Tier |
|---|---|---|
| Elite | 10+ numbers | 🔴 Elite |
| Above average | 8–9 numbers | 💎 Diamond |
| Average | 5–7 numbers | 🥇 Gold |
| Below average | 3–4 numbers | 🥈 Silver |
| Beginner | 1–2 numbers | 🥉 Bronze |
The global average is around 6 numbers. Most humans plateau between 6 and 8, which matches the findings of the original Kyoto research — Ayumu routinely performed at the 9–12 level. A score of 8+ on BrainRivals is genuinely impressive and puts you above average globally.
Why Humans Struggle Beyond 7 Numbers
The chimp test exposes a specific bottleneck in human cognition: the speed of visuospatial encoding.
When numbers appear, you have a fraction of a second to register their positions before they vanish. Humans typically process spatial information sequentially — scanning from one item to the next. This serial scanning can only register 5–7 positions in the available time window before the first click erases the display.
Chimpanzees appear to process the array more holistically — capturing the gestalt of the entire display in one rapid take, rather than scanning item by item. This parallel processing strategy is far more efficient for this specific task.
Importantly, this doesn't mean chimpanzees are generally smarter than humans. They excel at this narrow task because evolution shaped their visual memory system for exactly this kind of rapid spatial assessment.
Chimp Test vs. Other Memory Tests
| Test | What Disappears | Key Skill |
|---|---|---|
| Chimp Test | All numbers after first click | Instant spatial capture |
| Sequence Memory | Nothing (visible during recall) | Sequential tile order |
| Visual Memory | Pattern after study phase | Pattern recreation |
| Number Memory | Entire number after display | Phonological rehearsal |
The chimp test is uniquely unforgiving: unlike sequence memory (where tiles stay visible during the recall phase) or visual memory (where you get a study period), the chimp test gives you only a single, brief look at the full display before information begins to disappear. There's no opportunity for rehearsal.
The Role of Eidetic Memory
Eidetic memory (sometimes incorrectly called photographic memory) is the ability to recall images with high detail and accuracy after brief exposure. True eidetic memory — holding a perfect visual snapshot that can be "read" like a photograph — is extremely rare and may not exist in adults at all.
What chimpanzees appear to have is not quite eidetic memory either, but rather an exceptionally fast and accurate visuospatial encoding system that operates over a very short time window (approximately 200–500ms).
Humans can partially replicate this with training, but rarely reach the natural fluency that young chimpanzees demonstrate. Interestingly, younger children (5–9 years old) sometimes outperform adults on similar tasks, suggesting that the capacity may exist in humans but is overwritten as language and sequential reasoning develop.
7 Strategies to Improve Your Chimp Test Score
1. Scan the full array before clicking
Before you click the number 1, take a deliberate half-second to scan the entire grid and build your mental map. This front-loads your encoding and reduces the information lost when numbers start vanishing.
2. Chunk by spatial region
Instead of memorising each number's position individually, group them by screen region: "top cluster has 2 and 5; bottom-left has 3 and 7; centre has 4." Regional chunking is more efficient than position-by-position memorisation.
3. Trace a path
Mentally draw a connecting path through the numbers in ascending order before clicking. Imagining the route you'll take converts a memory task into a partial motor planning task, which is handled by different (and often more reliable) brain systems.
4. Use peripheral vision
Rather than fixating your eyes on one number and scanning, try to soften your gaze and take in the full array with peripheral vision. Peripheral processing is less detailed but faster, and for the chimp test, coverage matters more than precision.
5. Start with lower levels and build fluency
Don't immediately jump to the hardest level. Spend time building fluency at 4–5 numbers until your encoding feels automatic. Automaticity frees up cognitive resources for the harder encoding demands of higher levels.
6. Reduce cognitive interference
The chimp test is exquisitely sensitive to mental noise. Attempting it while tired, distracted, or immediately after cognitively demanding tasks produces significantly worse results. Test in a calm, focused state.
7. Practice spatial memory more broadly
The Visual Memory Test and Sequence Memory Test train overlapping spatial memory systems. Cross-training on these tasks builds the underlying visuospatial capacity that the chimp test draws on.
What Your Score Means
Reaching 6 numbers (Gold tier) means you're performing at the human average — which is already remarkable given that you're competing with a task specifically designed around a chimpanzee's natural cognitive strengths.
Reaching 8 numbers (Diamond tier) puts you in the top tier of human performers globally. It indicates fast visuospatial encoding, strong spatial working memory, and good inhibitory control.
Reaching 10+ numbers (Elite tier) is exceptional. At this level, you're likely using sophisticated spatial strategies and have extensively trained your visuospatial system. You may have Ayumu's measure — at least on a good day.
Take the BrainRivals Chimp Test
Ready to find out how you measure up against one of nature's most remarkable memory performers? Take the Chimp Test on BrainRivals and see where you rank on the global leaderboard.
Remember:
- Numbers appear, you click 1, then all others vanish
- Click the remaining positions in ascending order (2, 3, 4…) from memory
- Each successful round adds one more number
- The game ends when you click a wrong position
Frequently Asked Questions
Can humans ever beat chimpanzees at the chimp test?
Some humans, with extensive training, have matched Ayumu's performance on the original task. But on average, untrained adult humans perform significantly worse. Interestingly, chimpanzees' performance degrades with age — young chimps (like Ayumu at age 5–6) are considerably better than older ones, mirroring the human developmental pattern in reverse.
Is the chimp test a real IQ test?
No. The chimp test measures one specific cognitive capacity — rapid visuospatial encoding and short-term spatial memory. It doesn't measure reasoning, language, problem-solving, or general intelligence. A low score doesn't imply low IQ; it simply reflects a specific limitation in rapid visual snapshot capacity.
Why do younger children sometimes beat adults?
Young children (approximately 5–9 years) sometimes outperform adults on chimp-like tasks. The dominant theory is that the development of language and verbal thinking gradually "overwrites" the earlier, more holistic visual processing style. As verbal strategies dominate cognition, the raw visual capture ability diminishes. This mirrors the chimp vs. human difference at a developmental scale.
Does screen size affect performance?
Yes, significantly. On a larger screen, numbers are spread further apart, making the encoding task harder. On a small phone screen, numbers are clustered more tightly, making peripheral capture easier. For fair comparison, use a consistent device — ideally a desktop monitor or laptop.
How does the chimp test relate to ADHD?
People with ADHD often struggle particularly with the chimp test due to the combination of brief presentation time and the demand for rapid, complete encoding. Impulsive clicking (tapping before fully encoding all positions) is a common failure mode. Practising deliberate, systematic scanning — pausing before the first click — helps significantly.