Examples of restricted, repetitive patterns of behavior, interests, and / or activities include Stereotyped or repetitive movements or speech (eg, repeated hand flapping or finger flicking, repeating idiosyncratic phrases or echolalia, lining up toys) Inflexible adherence to routines and / or rituals (eg, having extreme distress with small changes in meals or clothing, having stereotyped greeting rituals) Highly restricted, abnormally intense, fixated interests (eg, preoccupation with vacuum cleaners, older patients writing out airline schedules) Extreme over - or under-reaction to sensory input (eg, extreme aversion to specific smells, tastes, or textures; apparent indifference to pain or temperature) Some affected children injure themselves.