O.C. experts say autism, aggression link uncertain - OC Register There appears to be a lack of definitive research about autism and aggressive behavior in children. In 2011, University of Missouri researchers surveyed the parents of 1,380 autistic children and adolescents and found that aggression appeared to be common. About 68 percent demonstrated aggression toward a caregiver and 49 percent toward non-caregivers. Aggression can vary in severity from tantrums to physical violence. Some area counselors say modifying diet, medicine and communication can help reduce it. In some cases, routine behavioral therapy may be needed.