Ravens make quick visual decisions

A recent study found that two common ravens made certain visual decisions about twice as fast as humans and primates in similar tasks. The ravens’ decision-making speed was impressive despite having a brain structure different from that of primates.

Experiment setup for raven decision-making

Researchers tested the ravens by placing them in front of a touchscreen showing a cloud of white dots on a black background. Some dots moved in one direction, while others moved randomly. The birds had to identify the dominant direction and select the correct button to get a mealworm as a reward.

Ravens performed well even with weak signals

The ravens performed better than chance, even when only 3% of the dots moved in the same direction. Their decisions remained better than random choices, and when the movement was clear, they achieved nearly 100% accuracy in selecting the correct direction.

Ravens made decisions in 235 milliseconds

From the appearance of the dots to the start of their head movement toward the button, the ravens took an average of 235 milliseconds. This time included visual processing, decision-making, and the start of the motor response.

Brain activity showed early decision signs

The researchers recorded the activity of 248 neurons in the NCL, a brain region in birds linked to complex cognitive functions. Some neurons began to change activity as early as 70 milliseconds after the visual stimulus, well before the birds made a motor response.

Raven brain speed may be due to multiple factors

The researchers suggested that the speed of decision-making could be due to a combination of processes, including the birds’ highly sensitive visual system and a compact brain structure. Their higher body temperature may also speed up neurochemical processes.

Study results may not apply to all birds

While the study highlights the intelligence of corvids like ravens, it remains unclear if this speed of processing is common to all birds. Many species may not have the same cognitive abilities as corvids, and further research is needed to determine this.