Selection and Learning Shape Communication Networks in the Dog Brain

Over tens of thousands of years of coevolution with humans, dogs have developed exceptional communicative abilities through both inherited adaptations and individual learning. Using diffusion MRI tractography in 108 dogs (50 males and 58 females), we disentangled how long-term selection and short-term training shape the neural architecture of communication. Comparing modern breeds to premodern dogs revealed that selective breeding for close interaction with humans has rewired communication-related networks, increasing hemispheric asymmetry and altering temporal and associative connectivity involved in vocal and lexical processing. In contrast, training induced localized plasticity: trained and released service dogs differed in sensorimotor and associative pathways supporting cue interpretation and response execution. Connectivity strength further predicted trainability, with higher behavioral scores linked to stronger cortical but weaker medial geniculate connections. Notably, trained dogs showed enhanced coupling between vocal premotor and secondary auditory regions associated with receptive vocabulary. Thus, the dog brain's communicative capacity reflects selection and experience acting across evolutionary and individual timescales.