What is human-directed aggression? By Will Bangura, M.S., CBCC-KA, CPDT-KA, (Dog Behaviorist) Certified Behavior Consultant. Human-directed aggression (HDA) in dogs refers to aggressive behaviors exhibited by dogs towards humans, which can range from growling and barking to biting. HDA is a serious issue that can have severe consequences for the dog and the humans involved. […]