July 3 (UPI) -- Neuroscientists in Canada have identified the neural circuit responsible for parrots' impressive intelligence.
The circuit is similar to the neural structure credited with providing primates their enhanced intelligence, an example of convergent evolution.
"An area of the brain that plays a major role in primate intelligence is called the pontine nuclei," said Cristian Gutierrez-Ibanez, a postdoctoral fellow in the psychology department at the University of Alberta, said in a news release. "This structure transfers information between the two largest areas of the brain, the cortex and cerebellum, which allows for higher-order processing and more sophisticated behavior."
The findings -- detailed this week in the journal Scientific Reports -- could also yield insights into the neural origins of human intelligence.
"In humans and primates, the pontine nuclei are large compared to other mammals," Gutierrez-Ibanez said. "This makes sense given our cognitive abilities."
The brains of birds feature a relatively small pontine nuclei, but another region called the medial spiriform nucleus offers enhanced connectivity between birds' cortex and cerebellum.
Though found in a different region of the brain, the medial spiriform nucleus, or SpM, works similarly to the small pontine nuclei.
"This loop between the cortex and the cerebellum is important for the planning and execution of sophisticated behaviors," said researcher Doug Wylie.
When scientists surveyed the size of the SpM among 98 different bird species, including chickens, owls and waterfowl, in addition to parrots, they found the psittacines had significantly larger medial spiriform nuclei relative to the size of their brains.
"The SpM is very large in parrots. It's actually two to five times larger in parrots than in other birds, like chickens," said Gutierrez. "Independently, parrots have evolved an enlarged area that connects the cortex and the cerebellum, similar to primates. This is another fascinating example of convergence between parrots and primates."
The enhanced region likely explains the self-awareness and tool-use abilities exhibited by parrots, researchers claim.
The discovery could help scientists better understand the role of the pontine nuclei in the human brain.
"This could present an excellent way to study how the similar, pontine-based, process occurs in humans," said Gutierrez. "It might give us a way to better understand how our human brains work."