Credit: Raul Hernandez/Eötvös Loránd University
Key points:
- Experiments with family dogs offer novel insights into the influence of food quality on dogs' motivation.
- The unique study combined behavioral and advanced neuroimaging data.
- The research focused on the dogs’ caudate nuclei, a brain region associated with reward processing.
A new study combining behavioral and neuroimaging data shows dogs’ food preferences are mirrored in their brain activity, particularly within their caudate nuclei—a brain region associated with reward processing. The study results offer novel insights into the influence of food quality on dogs' motivation.
Through two experiments, the study tested the influence of food quality on dogs' motivation to solve a problem, as well as their corresponding brain representations.
In the first experiment, 20 family dogs were trained to unwrap a box. The dogs were also taught to associate specific tones with two distinct food types: smoked ham, a highly rewarding treat, and fiber cookies, a less rewarding option. The results showed that the dogs unwrapped the box quicker when the sound associated with the higher quality food was played.
The second experiment involved a separate group of 20 family dogs, which were trained to remain still in a brain scanner. Initially, a scanning session exposed the dogs to both sounds, which held no meaning at this stage. Following this, the dogs participated in the wrapped box experiment. Finally, the dogs underwent another scanning session during which they listened to the sounds again, but this time, each sound had an association with either smoked ham or fiber cookies.
The focus of the brain analysis centered on observing changes in the caudate nucleus, a brain region linked to reward processing across species. Compared with the first session, the caudate nucleus exhibited a heightened response in the second session, responding more strongly to both sounds. It displayed an even more pronounced response to the sound associated with the highly rewarding smoked ham.
Of course, not all dogs had the same performance. The greater the discrepancy in the speed at which dogs unwrapped the two boxes, the more discernible their brain response patterns became for the two sounds in their right caudate nucleus.
“We were surprised to discover a distinct positive correlation between the behavior of the dogs and their brain representations,” said Laura Cuaya, first author of the study. “The direction of this relationship still intrigues us. Based on our data, we cannot determine whether a more distinct brain representation of both sounds enables a better behavioral performance or if it operates in the reverse. It’s likely that this process is not solely unidirectional.”