ASD-similar social behaviour scores affect stimulus generalization in family dogs

Abstract

Generalization, the tendency to respond in the same way to different but similar stimuli, is one of the main cognitive abilities that make category formation possible and thus is a prerequisite for efficiency in learning. Individuals with autism spectrum disorder (ASD) experience pervasive difficulty with producing generalized responses across materials, people, places, and contexts. Increasing evidence suggests that "ASD-like" social impairments appear endogenously and spontaneously in family dogs providing a high-validity model for understanding the phenotypic expression of human ASD. The present study aims to further investigate the dog model of ASD by the approach of searching for analogues in dogs showing "ASD-like" social impairments of cognitive phenomena in humans specific to ASD, specifically impairments of generalization abilities. We have tested 18 family dogs with formerly established "ASD-like" behaviour scores (F1, F2, F3) in a generalization task involving three conditions (size, colour and texture). We found a significant association between F1 scores and test performance as well as improvement during testing sessions. Our study provides further support for the notion that dogs with lower social competence-similarly to humans with ASD-exhibit attentional and perceptual abnormalities, such as being sensitive to minor changes to a non-adaptive extent.

Keywords: Dog; Generalization; Minor differences; Social competence; “ASD-like” behaviour.

Figure 1

3-D representation of the distribution of subjects based on the 3 ISRS factor scores (F1: Contact seeking and synchronization; F2: Behaviour toward strangers; F3: Attention to human communicative signals).

Figure 2

Experimental arrangement. Blue circles represent the objects’ location (1–4) for the Training and Test phases. E = position of the Experimenter, O = position of the owner, D = starting position of the dog. The grey rectangle shows the location of the door used in the experiment.

Figure 3

Objects of the experiment. First row: Basic set of objects used in the Preference, Pre-training, Training and Test warm-up trials. Second row: objects used in the ‘Colour change’ condition. Third row: objects used in the ‘Texture change’ condition. Fourth row: Objects used in the ‘Size change’ condition. Objects’ category names from the left to the right: box, skittle, case, cup, shoe, spoon.

Figure 4

Summary of the procedure with example target- and non-target objects.

Figure 5

Dogs’ performance during test conditions.

Figure 6

Association between the total number of correct choices during the test trials in the three different conditions and F1 factor scores extracted from ISRS questionnaire (GLMM, F_1,644 = 11.898; p = 0.001).

Figure 7

Association between delta scores during test trials (i.e. difference in performance between the last- and first four test trials) and ‘Contact seeking and synchronization’ (F1) scores extracted from ISRS questionnaire (parameter estimate(F1): 0.914, χ²₍₁₎ = 3.9, p = 0.048).