This episode is about a difficult aspect of autistic life and includes discussion about the urge to give yourself physical pain to get some relief from extreme emotions. You may want to avoid this one if you feel fragile or if children are around. Meltdowns are an outward explosion of emotions whereas shutdowns are when some autistic people internalise what’s happening and withdraw and go quiet as a result. Robyn holds onto her support bat Henry as she relives her most recent meltdown and describes the impact it had. We phone autistic mum of autistic kids Shona Murphy who is an expert on "behaviour that challenges" - learning to punch a pillow rather than throw an iPad are the kind of tactics she advocates. Another guest, Jonny Profane, had shutdowns for 60 years and didn't know why until he was diagnosed recently. He talks about the Embarrassment and shame he feels when they happen. This podcast is longer than usual because the presenters weren't ready to leave when the producer said they could leave, so they kept talking. The final 15 minutes of this episode are even more raw and honest than usual. With Robyn Steward, her support bat Henry, Jamie Knight and Lion. Produced by Emma Tracey. Subscribe to the podcast on BBC Sounds or say "Ask the BBC for 1800 Seconds on Autism" to your smart speaker. Email stim@bbc.co.uk