Table 1. Eigenvalue of the first principal component (PC1, denoted “relationship”) derived by the PCA on the outcomes of the behavioural tests, variance explained, and loadings of the behavioural variables.

	PC1
Eigenvalue	1.97
Variance explained	0.56
Loadings
AD familiar	-0.34
Touch score familiar	0.39
AD unfamiliar	-0.35
Touch score unfamiliar	0.39
Latency to 1m	-0.41
Latency to contact	-0.40
Duration of contact	0.37