A 2017 study by Ivaylo Iotchev and colleagues, published in Scientific Reports, investigated the role of sleep spindles—brief bursts of brain activity in the sigma frequency range (9–16 Hz)—in dogs. These spindles are already known in humans and rodents to contribute to sleep-dependent memory consolidation and sleep stability.
Using an automated detection method adapted from studies in children, the researchers quantified spindle-like activity in dogs for the first time and tested whether it had functional correlates similar to humans. They found that the density of EEG transients during non-REM sleep was associated with better memory performance during recall tasks.
The study also revealed a notable sex difference: female dogs showed a higher number of transients per minute compared to males. Importantly, spindle density was greater in learning conditions, and this increase correlated with improved recall performance, suggesting that these EEG features are functional analogues of human spindles.
These findings provide strong evidence that dogs share key sleep-related mechanisms with humans, making them a valuable comparative model for studying memory consolidation, cognition, and sleep physiology.
Source: Iotchev, I., Kis, A., Bódizs, R., Luijtelaar, G., & Kubinyi, E. (2017). EEG Transients in the Sigma Range During non-REM Sleep Predict Learning in Dogs. Scientific Reports, 7.
