New research shows that the neurotransmitter GABA, which has been connected to autism, is involved in the production of unwanted thoughts. Specifically, hippocampal GABA (would anyone be surprised to learn the hippocampus is also involved in autism?).
“Our ability to control our thoughts is fundamental to our wellbeing,” explains Professor Michael Anderson from the Medical Research Council Cognition and Brain Sciences Unit at the University of Cambridge. “When this capacity breaks down, it causes some of the most debilitating symptoms of psychiatric diseases: intrusive memories, images, hallucinations, ruminations, and pathological and persistent worries. These are all key symptoms of mental illnesses such as PTSD, schizophrenia, depression, and anxiety.”
I have always had a hard time suppressing thoughts, and I have been known to go over and over and over and over and over situations, replaying them and thinking of everything I could have and should have said. You may note other typically autistic symptoms in Dr. Anderson’s list, most notably anxiety.
The inability to control one’s thoughts is likely related to the weak executive functioning we on the spectrum have as well. After all, weak executive functioning makes it hard to not only control one’s thoughts, but to control expressing those same thoughts. While they may be two different systems, would it be surprising if it were found they were connected?