Immobility experiments with dogs of the Arkansas Line of Nervous Pointers.

As demonstrated in four experiments, dogs and pups of the Arkansas Line of Nervous Pointers, in contrast to kennel-mate dogs of the normal line, respond to manual inversion and brief restraint in an open sling with prolonged, mainly hypertonic, immobility. This response is consistent and replicable. At least in 4-month-old pups, the duration of sling immobility is positively correlated with the degree of behavioral pathology as determined by the objective Human Interaction Test. We found no evidence of basic difference between upright freezing and supine immobility.