A preliminary analysis of the effect of individual differences on cognitive performance in young companion dogs

Abstract

Many factors influence cognitive performance in dogs, including breed, temperament, rearing history, and training. Studies in working dog populations have demonstrated age-related improvements in cognitive task performance across the first years of development. However, the effect of certain factors, such as age, sex, and temperament, on cognitive performance in puppies has yet to be evaluated in a more diverse population of companion dogs. In this study, companion dogs under 12 months of age were tested once on two tasks purported to measure aspects of executive function: the delayed-search task (DST) and the detour reversal task (DRT). Owners also filled out the Canine Behavioral Assessment and Research Questionnaire (C-BARQ) to evaluate how temperament influenced task performance. Contrary to prior research, performance did not improve with age on either task. However, the lack of age effects was likely the result of small sample sizes and individual differences across other factors influencing performance. Specifically, temperament differences as measured by the C-BARQ subscales for nonsocial fear and excitability predicted task performance on the DST, but the effect of temperament on task performance differed between males and females. Excitability also predicted performance on the DRT, but the effect depended on the age of the dog. In addition, no correlations were observed between task measures, indicating a lack of construct validity. Overall, these findings provide a preliminary analysis of factors that appear to influence cognitive task performance in young companion dogs and highlight suggestions for future research evaluating the impact of individual differences on cognitive performance.

Keywords: Cognition; Development; Executive function; Individual differences; Puppies.

Fig. 1

Illustration of the test set-up for the DST (not drawn to scale). Experimenter 1 (E1) held the puppy (represented by the star) at the starting location. Experimenter 2 (E2) placed the reward in one of the three buckets (represented by the circles) and then returned to the starting position behind the middle location facing away from the puppy

Fig. 2

Illustration of the test set-up for the DRT (not drawn to scale). Experimenter 1 (E1) held the puppy (represented by the star) at the starting location, a 1 × 1 m square marked by tape on the ground. A barrier separated the puppy from Experimenter 2 (E2) with the reward so that the puppy had to navigate around the barrier through an opening on one side of the room. A correct choice was defined as the puppy stepping out of the starting location with at least one front paw on the side corresponding to the barrier opening. During the reversal phase of the task, the barrier was moved so that the opening was switched to the opposite side of the room

Fig. 3

Percent correct as a function of increasing delay on the delayed-search task. Confidence bands represent 95% confidence intervals (CI)

Fig. 4

Interaction between sex and nonsocial fear on overall percent correct on the delayed-search task. The blue line indicates the function of nonsocial fear and percent correct for females (n = 13), and the orange line indicates the same function for males (n = 10). Confidence bands represent 95% CI

Fig. 5

Interaction between sex and excitability on overall percent correct on the delayed-search task. The blue line indicates the function of excitability and percent correct for females (n = 13), and the orange line indicates the same function for males (n = 10). Confidence bands represent 95% CI

Fig. 6

The difference score (i.e., latency on the first reversal trial – latency on the last acquisition trial) on the detour reversal task as a function of excitability for varying ages (orange = mean – 1 SD; blue = mean; green = mean + 1 SD). The lines illustrate predicted linear trajectories for each age with confidence bands representing 95% CI. A larger difference score indicates a greater increase in latency (i.e., the puppy took more time to navigate around the barrier) on the first reversal trial relative to the last acquisition trial