Carrion crows clock 235 ms visual decisions in reported study

Two crows judge the direction of moving dots

According to the report, researchers trained two hand-raised carrion crows to identify the direction of moving dots by pecking a target.

They recorded 248 neurons in the nidopallium caudolaterale (NCL), an avian brain region described as a functional counterpart to the primate prefrontal cortex. Fifty-eight sampled neurons reportedly differed by the direction the bird would choose and began showing that signal about 70 milliseconds after the dots appeared.

The report compares the crows’ result with closely matched monkey-task studies that recorded reaction times of roughly 410, 490, and 600 milliseconds. It does not establish a general decision-speed baseline for all birds or mammals.

In the reported experiment, two carrion crows averaged 235 milliseconds from the dots appearing to the start of a head movement toward their choice. The article says their accuracy was comparable to that of monkeys or humans in the same task, while their recorded neural activity showed a decision-related signal.

Early neural signals within a limited experiment

The reported result links fast performance in a matched visual task to a decision-variable signal—a running neural tally of evidence—in a bird brain organized differently from a mammalian cortex. Its scope is limited: it involved two crows, one task, and does not establish whether the finding applies beyond crows or other corvids.