Puppies are known for tilting their heads, especially when they hear new or interesting words or sounds. They may also do this when they see something they find strange and fascinating. They may tilt to one side and then return to normal and then tilt to the other side, this behavior is most common in puppies, it is considered normal for dogs of all ages.
Head tilt can sometimes be a sign of a serious health problem. In most cases, health-related head tilting is involuntary. The head tilt will likely occur constantly ,normal head tilt is intermittent and occurs in response to stimuli, an abnormal head tilt may be accompanied by other signs of illness such as involuntary eye movement (nystagmus), dizziness, drunken gait (ataxia), weakness, nausea, and/or lethargy.
An abnormal head tilt is typically caused by some kind of vestibular dysfunction. Located in the middle/inner ear and brain stem, the vestibular system is responsible for balance and coordination. Inflammation of the ear or problems in the brain can affect the nerves and structures of the vestibular system. This inflammation can lead to head tilt and other signs of vertigo.