I have been struggling with this issue with my 4.5 year old level 3 nonverbal son.. he is obsessed with hair.. pulling, parting, inspecting.. he also scratches and hits and thinks it’s so funny. He doesn’t understand he’s hurting me. I did just buy him one of those hair styling heads.. a Disney one that has long hair for him to play with.. so far he seems interested in it.. maybe try something like to redirect him away from your wife. 🙏🙏

I don't have any insight, but my four year old is being verbally beligerant and seems honestly confused when he gets on trouble. He thinks he's being funny. We have been trying to explain that other people have feelings, but it's not going too far.

I understand your frustration. My 4 year old son with ASD likes to touch my lips, incessantly. He pulls my bottom lip down and even tries to stick his fingers and hand in my mouth. I want to encourage him to self soothe but I don't want to taste everywhere he's been. Maybe trying some emotion cards, sad or hurt when he starts to scratch or pull your hair.

In autism, skin scratching can be a form of self-stimulatory behavior, or "stimming," used to manage sensory input and regulate emotions Addressing sensory sensitivities, managing anxiety, or redirecting scratching behavior with alternative stimming activities. Provide alternative sensory input: Offer items with different textures, provide opportunities for movement, or create a calming environment.
Teach coping mechanisms: Help the individual develop healthy ways to manage stress and anxiety