Human Handlers May Influence Drug Detection Dogs

Researchers at UC Davis have found that drug and explosive sniffing canines' behavior may be affected by their human handlers' beliefs and their unintentional, subtle clues. According to an article in the San Francisco Chronicle, a study published in the January issue of the Journal Animal Cognition found that when their human handlers believed that a scent was present, specially trained detection-dog teams, over 200 times mistakenly "alerted" to a scent when no scent was present. Lisa Lit, the study's lead author, is a postdoctoral fellow in the Department of Neurology at UC Davis. She said, "It isn't just about how sensitive a dog's nose is or how well-trained the dog is. There are cognitive factors affecting the interaction between a dog and a handler that can impact the dog's performance." So it appears that even the most sensitive canine's schnozzola may be trumped by the interactional relationship with his or her handler. Anita M. Oberbauer, the study's senior author and chair of the Department of Animal Science at UC Davis said, "Dogs are exceptionally keen at interpreting subtle cues, so handlers need to be cognizant of that to optimize the overall team performance." For the research project, 18 handler-detection dog teams were recruited for the study. All were certified by an agency for either drug detection, explosives detection or both, chosen from law-enforcement agencies to evaluate how handler's expectations and beliefs might impact the performance of detection-dogs. All the dogs were trained to passively alert by sitting or laying down, actively alert by barking, or doing both. Teams were comprised of 14 male dogs, 4 female dogs. The breeds included were Labrador retrievers, German shepherds, Dutch Shepherds, and Belgian Malinois. Human partners had up to 18 years experience dog-handling, with dogs ranging from 2-7 years experience. In order to ensure the unlikelihood of the former presence of drugs or explosives, a church was chosen for the location of the study. Additionally none of the dogs or humans had ever been to that location before. Dividing the location into 4 rooms, the handlers were told that there might be three target scents in each room. Materials representing scents were placed in three of the rooms. And while there were no real targets placed in any of the rooms, interestingly there were three alerts made in each of them, demonstrating that the expectations of the handlers influenced the dogs to "alert". And while Lit doesn't want to minimize the actual skill of these teams, she believes that her findings are significant and hopes to be able to replicate them in other studies. However, it does give one pause to consider how often these teams make mistakes, with the concomitant need for careful training of handlers, don't you agree? Leave a comment to share your opinions. Image Source: Flickr user marcokalmann