Crows are among the most intelligent animals in the world, protagonists of countless studies that have demonstrated their ability to solve complex problems, build tools, plan for the future and even do arithmetic. Part of this intelligence is linked to the extraordinary speed of their brain: when they have to make a decision based on visual stimuli, their reaction time is 235 milliseconds, which is about half of what it takes for monkeys (and us humans) to act. This is demonstrated by a study by the University of Tübingen, published on Science.
The crows are faster than you
The study involved two crows, who were taught to solve a classic “visual motion discrimination task“, a task based on the reaction to moving images. In this case, a screen showed an aggregate of white dots, programmed to move in semi-random directions, with a tendency to move more to the right or more to the left. The crows were asked to peck the screen at one of two points, one located to the right of the mass of dots and one to the left, depending on the direction identified.
The most obvious result is that the crows are extremely precise in identifying the average direction of a mass of randomly waving dots: the two involved in the study gave the correct answer in (almost) 100% of the cases. The most interesting aspect, however, concerns the speed with which they made the decisions: as mentioned, on average it took them 235 milliseconds, i.e. half of what it would take a human. Even faster is the speed with which they react and begin to set their cognitive machine in motion.
Why do crows decide so quickly?
The researchers in fact monitored the brain, in particular the region called the caudolateral nodopallium, which from a functional point of view has the same role as the prefrontal cortex of mammals, and therefore has “executive” functions, impulse control and decision making. They thus discovered that the crows’ brains activate on the required task in 70 milliseconds, turning on the first signals linked to the recognition of a direction. Once a certain activation threshold is exceeded, the decision is made and the bird acts.
The study therefore demonstrates that the brain of crows makes decisions in a similar way to how primates do, despite having a different structure and organization.
And it shows that it does it very quickly. It could be, according to the authors, an adaptation to their lifestyle: when flying, they need to make very precise decisions very quickly, especially when they are going hunting.
