Visual continuum in non-human animals: serial dependence revealed in dogs

Area of Science:

• Cognitive Science
• Animal Behavior

Background:

• Serial dependence influences perception by biasing current stimulus evaluation based on prior attended stimuli.
• This phenomenon is thought to stabilize conscious experience through temporal integration.
• While studied in humans, its presence in other species remains unexplored.

Purpose of the Study:

• To investigate the occurrence of serial dependence in dogs.
• To determine if dogs' perception of quantity is influenced by preceding task-irrelevant stimuli.

Main Methods:

• Dogs were trained on a quantity discrimination task.
• A task-irrelevant stimulus preceded one of the discriminanda in a subsequent trial.
• The influence of the preceding stimulus on quantity perception was analyzed.

Main Results:

• Dogs exhibited serial dependence, perceiving quantities as closer to the preceding stimulus.
• The observed effect in dogs was comparable in direction and strength to that in humans.
• Analysis of dogs' attention suggested the use of distinct quantity estimation mechanisms.

Conclusions:

• Serial dependence is present in dogs, providing the first evidence beyond humans.
• This suggests a shared perceptual mechanism across phylogenetically distant mammals.
• The findings indicate sophisticated cognitive processes in dogs' quantity estimation.