The Brain of a Crow is Remarkably Fast? The Capability of a Small Brain Demonstrated by "Decisions Made About Twice as Fast as Humans"

Crows observing our movements in parks or in front of stations. Have you ever felt that they seem quite intelligent when you catch their gaze?

A new experimental result has added to that impression. A research team from the University of Tübingen in Germany confirmed that crows can respond in an average of 235 milliseconds, or 0.235 seconds, in a task that involves distinguishing movements on a screen.

When compared to previous studies on humans and monkeys, this speed is roughly twice as fast. Moreover, it doesn't seem like they're just rushing to answer.

The research has highlighted the surprising processing capabilities of a small brain and the "decision-making mechanism" shared by the brains of different animals.

A simple yet challenging test of responding to moving dots

The research was conducted by Philipp Schmidbauer and Andreas Nieder. The results were published in the scientific journal "Science" on October 22, 2026.

The experiment involved two crows, known as "carrion crows" in English, that were raised by humans.

In the task, numerous white dots are displayed on a black screen. Some of them move in the same direction, while the rest move randomly. The crows must determine the overall direction of flow and peck at the corresponding target with their beaks. If correct, they receive a mealworm as a reward.

If many dots move in the same direction, the flow is easy to discern. However, if only a few dots move together, the crows must pick up clues from the chaotic movements.

This is not a test of simply reacting reflexively to something that lights up. It is a task of observing information that changes over time and determining which direction it is moving.

Not just fast—choosing the correct answer with minimal clues

In the experiment introduced by Ars Technica, the proportion of dots moving in the same direction was varied to adjust the difficulty of the judgment.

Even under conditions where only 3% of the dots moved in the same direction, the two crows performed better than if they had chosen randomly. Under conditions with clear clues, the university reported that the accuracy rate reached nearly 100%.

The average time from when the stimulus appeared to when the crows began to move their heads to answer was 235 milliseconds.

In previous studies on similar tasks with monkeys, values of approximately 410 milliseconds, 490 milliseconds, and 600 milliseconds have been reported. The crows' response was significantly shorter than these.

Answering quickly could potentially increase errors. However, in this case, the explanation that crows prioritized speed and significantly reduced accuracy did not match the experimental results.

The researchers did not force the crows to answer as quickly as possible. Even when allowed to judge at their own pace, the crows were swift.

It doesn't mean "twice as fast as humans" in everything

It's important to be cautious about how we interpret the "about twice" figure.

This study did not involve a direct competition where crows and humans used the same equipment in the same venue. The comparison of speed with humans and monkeys uses past research results with similar tasks.

Additionally, crows answered with their beaks, while some experiments with monkeys involved indicating choices through eye movements. The time from seeing the stimulus to reacting involves not only visual processing and judgment but also preparation for movement.

Therefore, the 235 milliseconds cannot be reinterpreted as "pure thinking time."

Of course, this does not mean that crows outperform humans in decision-making time when shopping, understanding the meaning of conversations, or planning for the future.

This discovery is about crows achieving both speed and accuracy in a specific task of distinguishing the direction of moving dots. By understanding this scope, the interest of the findings becomes clearer.

Different brain structures, but similar decision-making processes

Another important aspect of the study is that it recorded the brain activity of crows until they reached an answer.

The team investigated a brain region called "NCL," which is involved in advanced information processing in birds and is thought to functionally correspond to the prefrontal cortex in primates.

According to Ars Technica, out of the 248 neurons recorded, 58 showed different activities depending on which direction the crow ultimately chose. This difference appeared at an early stage, about 70 milliseconds after the dots were displayed.

This 70 milliseconds is not the time when the decision was fully completed. It means that signals related to later choices were already beginning to appear.

Primate decision-making is explained by a mechanism where visible information is gradually accumulated, and a choice is made once a certain threshold is reached. The neural activity of crows also had features consistent with this.

For example, when judging whether a distant figure is an acquaintance, confidence increases as clues such as clothing and walking style accumulate. Although the task is different, the idea of accumulating information to reach a decision is easy to understand when imagining such a scenario.

Birds do not have the same layered structure as the mammalian neocortex. Nevertheless, it is possible that brains with different structures use similar computational principles. This goes beyond a mere speed competition and is a highlight of this study.

Is a small brain and high body temperature supporting the speed?

Why can crows react so quickly?

Currently, the cause has not been identified. Nieder explained to Ars Technica that rather than having one extremely fast process, multiple processes might be progressing quickly.

One candidate is the compactness of the brain.

If nerve cells are densely packed in a small space and the wiring between cells is short, it might reduce the time it takes to transmit information. While having a large brain has its advantages, there is also strength in being able to connect processes over short distances.

Another candidate is the high body temperature of birds. Nieder pointed out that birds can have body temperatures reaching 41–42 degrees Celsius, which might affect the speed of reactions related to neural transmission.

However, this experiment did not change body temperature or manipulate wiring length to confirm causality. Both need to be considered as hypotheses to explain the speed.

Flying while avoiding obstacles, determining landing spots, and accurately pecking at food. Many aspects of a bird's life require quick visual processing and coordination of movements. These demands may have been related to the evolution of processing capabilities.

Surprise at the ability on social media and thoughts about its relation to flight

Regarding this study, posts have been seen on the overseas bulletin board-style social media "Reddit."

In communities about crows, there were reactions suggesting that the abilities of crows are underestimated, and comments considering that fast information processing is necessary to fly without hitting obstacles.

In biology communities, there were humorous reactions with people jokingly claiming they could decide faster than crows. The comparison of "faster than humans" seems to serve as an entry point for interest in the study.

However, these are summaries of individual posts that could be confirmed and do not represent the overall opinion of social media or the reactions of Japanese readers. Additionally, comments about the relationship between flight and processing speed do not prove causality.

The surprise at the research results and the fun of imagining the reasons. Both are leading to interest in news about familiar birds.

Does this apply to crows on the streets of Japan as well?

For those of us living in Japan, crows are very familiar creatures. We might see them at garbage collection sites or observing their surroundings on power lines and in parks.

However, what was measured this time were two crows that had learned the task. It cannot be concluded that all crows in Japanese cities make judgments at the same speed.

Furthermore, it is still unclear whether this speed is a characteristic of birds in general or a particularly excellent trait of the crow family.

The small number of individuals is an important limitation. Although there are practical difficulties in combining complex tasks and recording neural activity, additional verification is needed to extend the discussion from two individuals to the entire species and further to all birds.

Nevertheless, this study slightly changes the way we view familiar crows.

We tend to measure intelligence by abilities similar to humans, such as the ability to use language or solve complex problems. However, the ability to quickly pick up clues from chaotic visual information is also an important aspect of intelligence for survival.

A small brain does not necessarily mean small processing capabilities. By studying brains designed differently from humans, we can gain a broader perspective on what it means to make judgments.

Sources

1. Ars Technica:
   Details of the task, reaction time, neural activity recording, interviews with researchers, and research limitations confirmed.
   https://arstechnica.com/science/2026/10/crows-can-evaluate-visual-info-twice-as-fast-as-mammals/

2. University of Tübingen research announcement (published on idw): Confirmation of experimental results and research positioning.
   Confirmation of the average reaction time of 235 milliseconds, high accuracy under clear conditions, and neural signals appearing about 70 milliseconds later.idw-online.de
   https://idw-online.de/en/news879357

3. Science published paper "Ultrarapid decision-making in an avian brain": Original research paper.
   Authors are Philipp Schmidbauer and Andreas Nieder. Details confirmed mainly through attached articles and university announcements due to restricted direct access to the text.
   https://doi.org/10.1126/science.aed6459

4. Reddit・r/crows: Reactions about the abilities and visual processing of crows.
   Summary of comments confirmed in search results. Not indicative of overall trends on social media.reddit.com
   https://www.reddit.com/r/crows/comments/1xd46xs/interesting_article_i_hope_its_not_a_repeat/

5. Reddit・r/biology: Reactions to posts introducing the research.
   Humorous comments about the decision-making speed of humans and crows confirmed in search results.reddit.com
   https://www.reddit.com/r/biology/comments/1xdsvmm/crows_may_make_some_decisions_twice_as_fast_as/