Dementia is often thought of as something that happens later in life, but doctors say symptoms of some forms of dementia can begin much earlier, including in a person's 40s.

September is World Alzheimer's Month, making it an important time to raise awareness about the signs of dementia and the importance of catching changes early.

Dr. Jessica Shultz, a neurologist with Memorial Hermann, says people may not recognize that early-onset dementia symptoms can appear at a relatively young age.