In their new paper in the Philosophical Transactions of the Royal Society B, Ruhr University Bochum researchers Gianmarco Maldarelli and Onur Güntürkün highlight three central areas in which birds show remarkable parallels to conscious experience in mammals: sensory consciousness, neurobiological foundations, and accounts of self-consciousness.
Maldarelli & Güntürkün show that there is growing evidence that (i) birds have sensory and self-awareness, and (ii) they also have the neural architecture that may be necessary for this. Image credit: Kutte.
Firstly, studies of sensory consciousness indicate that birds not only automatically process stimuli, but subjectively experience them.
When pigeons are presented with ambiguous visual stimuli, they shift between various interpretations, similar to humans.
Crows have also been shown to possess nerve signals that do not reflect the physical presence of a stimulus, but rather the animal’s subjective perception.
When a crow sometimes consciously perceives a stimulus and does not at other times, certain nerve cells react precisely according to this internal experience.
Secondly, birds’ brains contain functional structures that meet the theoretical requirements of conscious processing, despite their different brain structure.
“The avian equivalent to the prefrontal cortex, the nidopallium caudolaterale (NCL), is immensely connected and allows the brain to integrate and flexibly process information,” Dr. Güntürkün said.
“The connectome of the avian forebrain, which presents the entirety of the flows of information between the regions of the brain, shares many similarities with mammals.”
“Birds thus meet many criteria of established theories of consciousness, such as the Global Neuronal Workspace theory.”
Thirdly, more recent experiments show that birds may have different types of self-perception.
Even though some species of corvids pass the traditional mirror test, other ecologically significant versions of the tests have shown further types of self-consciousness in other bird species.
“Experiments indicate that pigeons and chickens differentiate between their reflection in a mirror and a real fellow member of their species, and react to these according to context,” Dr. Güntürkün said.
“This is a sign of situational, basic self-consciousness.”
The findings suggest that consciousness is an older and more widespread evolutionary phenomenon than had previously been assumed.
Birds demonstrate that conscious processing is also possible without a cerebral cortex and that different brain structures can achieve similar functional solutions.
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Gianmarco Maldarelli & Onur Güntürkün. 2025. Conscious birds. Phil. Trans. R. Soc. B 380 (1939): 20240308; doi: 10.1098/rstb.2024.0308
