Dr. Adam Brenner and Dr. Preston Wiles at the University of Texas Southwestern Medical Center in Dallas says some early warning signs of mental illness include:
-- Loss of interest in previously enjoyed activities such as spending less time with friends, quitting sports or other extracurricular activities.
-- Decline in functioning such as failing at school or no longer keeping up with regular chores at home.
-- Suspiciousness or strong nervous feelings such as spending excessive time alone in their room, or acting as though they are "being watched."
-- Changes in sleep, appetite or personal hygiene such as staying up all night, requiring frequent reminders to bathe or change clothing.
-- Problems with concentration, memory or speech such as talking in a disorganized or unusual way, talking too fast, or jumping between unrelated topics.
"It is often difficult for young people who are suffering from mental illness to be aware of changes in their thinking, feelings or behavior," Brenner said in a statement. "It may be a family member, friend or teacher who first notices the signs of the illness."
What should someone do who notices these signs in my child or teen? Brenner says a gentle talk with the child or adolescent about your concerns may be a good first step.
"They may already have noticed something but have been too ashamed or frightened to discuss it," Brenner says. "Consulting your primary care doctor or school counselor may also be beneficial when deciding how you can best help your child. Most importantly, if there is any concern that a person is a danger to themselves or others, either by voicing ideas of suicide or talking about shooting or harming others, call 911 or take the person to the nearest emergency room for assistance."
2014: The Year in Music [PHOTOS]