Structures of bird brains and their relationship to cognitive capacity, metabolic costs and limitations to brain growth
Final Report Abstract
This DFG project set out to get a better understanding of the cornerstones that give rise to avian complex cognition by executing a comparative analysis of the higher associative area NCL, and investigating the neuronal energy budget. Our work demonstrates that the NCL is highly variable across both closely and distantly related species, and that with more complex behaviour we observe an expansion of the NCL-like territory with an increase of dopaminergic innervation and a possible parcellation into neuroanatomical and functional subunits. Our findings will also function as a starting point to re-evaluate the definition of the NCL, and possibly higher-order areas across the vertebrate class. Our second major finding revealed that a neuron in the bird brain consumes three times less glucose compared to the average mammalian neuron. This is an important part of the explanation how birds are able to maintain such high numbers of neurons required to build complex networks that give rise to these impressive avian behaviours. Thus, we propose as additional building blocks of avian complex cognition (besides a small nucleated brain with high neuronal densities): an expanded and differentiated higher-order area, and low metabolic costs per neuron to sustain a multitude.
Publications
- (2018). fMRI reveals a novel region for evaluating acoustic information for mate choice in a female songbird. Current Biology, 28(5), 711-721
Van Ruijssevelt, L., Chen, Y., von Eugen, K., De Groof, G., Hamaide, J., Verhoye, M., Güntürkün, O., Woolley, S. C. & Van der Linden, A.
(See online at https://doi.org/10.1016/j.cub.2018.01.048)