Yelling At Your Dog Can Have Long-Term Negative Effects, Study Shows .br An analysis says using br negative commands can result br in long-term stress for your pooch.br The study can be found br in the journal BioRxiv.br Besides stress, it adds that a br dog's cognitive abilities can br be also be affected.br For the study, 92 dogs from training facilities br in Portugal were put into two groups.br One group was trained aggressively br and had choke collars used on them.br The other went through training in a docile manner br with rewards coming in the form of treats.br The three-year study saw the dogs br go through multiple stress tests.br In one, negatively-trained dogs approached bowls of food slower br than the other, a sign of pessimism.br "Dogs trained using aversive-based methods experienced poorer welfare as compared to companion dogs trained using reward-based methods ..."br - Researchers, via study.br "Dogs attending schools using aversive-based methods displayed more stress-related behaviors ..."br - Researchers, via study.