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When separated from their owners dogs express distress. They cry, bark, scratch at the door, and even stop eating. Separations are occasionally necessary. After all, people go to work and take vacations. And, dogs might have to go to the vet. A very interesting study conducted by Sumegi, Garci, and Topal (2014) shows that separation related behaviors previously treated with sedatives can be brought under behavioral control with conditioning and placebos.
In a study aimed to investigate the role of placebos in reducing dogs’ separation distress, Sumegi et al. randomly assigned 28 dogs to two conditions: Conditioned and Control. Dogs in the conditioned group were administered liverwurst and a sedative and observed after their owner left the room. The Control Group was treated identically except they were given liverwurst and a vitamin. To test the effectiveness of the intervention (sedative or vitamin), both groups of dogs were given vitamins only, (no sedative) with the liverwurst and their owners were instructed to leave the room. On these final test trials, the conditioned group (dogs who had received the sedative) were significantly more passive and showed fewer distress behaviors (eg. barking, crying, and scratching the door) even though they had received a vitamin only and not a sedative.
The authors interpret these results as a conditioned placebo effect and discuss implications for treating separation anxiety in dogs. Personally, I think the sedated dogs were desensitized to the room and being left alone. The desensitization then transferred to the final test trial without a drug. At any rate, this is a very interesting study. For more details and to form your own opinion, follow this link: Sumegi, Z., et al., Conditioned placebo effect in dogs decreases separation related behaviours. Appl..Anim. Behav. Sci. (2014). http://dx.doi.org/10.1016/.applanim.2014.07.005.
