Two carrion crows named Iggy and Lemmy made visual decisions in an average of just 235 milliseconds when put to the test. The birds evaluated moving visual stimuli and acted on them nearly twice as fast as humans and other primates, according to research published in the journal Science. Neuroscientists Philipp Schmidbauer and Andreas Nieder conducted the study at the University of Tübingen in Germany.
The crows sat before a touchscreen displaying moving white dots during the experiment. Their task was to determine whether the majority of the dots traveled to the left or right, communicating their choice by pecking a target on the corresponding side of the monitor.
Some dot patterns offered clear movement signals. Others were difficult to interpret.
Even when the patterns were hard to recognize, the crows made decisions that exceeded random chance. With clear signals, they achieved an accuracy rate approaching 100 percent, according to Yahoo.
The Tübingen team compared these results against six earlier studies involving primates. Monkeys required approximately 410 to 600 milliseconds to make comparable visual decisions.
Humans took between 450 and 820 milliseconds, as reported by Zmescience.
Inside the Avian Brain
The researchers recorded the activity of individual neurons within a brain structure known as the nidopallium caudolaterale to see how the birds reached decisions so rapidly. This region governs information processing and decision-making in birds, performing a function comparable to the prefrontal cortex or neocortex in mammals.
The recordings indicated that the crows’ brains began distinguishing between leftward and rightward movement just 70 milliseconds after the dots appeared on the screen.
Neural activity then increased gradually as the birds processed the visual information. It functioned similarly to a neural tally that pushed the brain toward a choice.
Andreas Nieder noted that these neuronal dynamics align with established decision-making models observed in humans and non-human primates. These cognitive similarities exist despite anatomical divergence.
Unlike humans and other mammals, whose complex thinking occurs in a six-layered cerebral cortex, birds lack a layered cerebral cortex entirely. They instead possess a forebrain pallium where nerve cells are organized into clusters.
Evolutionary Pressures Shape Avian Vision
Researchers suggest that the exceptional speed of avian visual processing may be tied to the demands of everyday life.
Dodging obstacles and precisely guiding a beak toward food require rapid visual interpretation. If birds spent too long weighing their options, survival could be compromised.
This study builds on earlier work from the same research team.
In 2020, findings suggested that crows’ brains respond differently depending on whether the birds notice what they see, pointing toward a basic form of conscious awareness. A 2024 study demonstrated that crows can count out loud by producing specific numbers of calls when prompted.