Thyroid does control the way our thoughts and intelligence levels are. There are hundred of Dx's out there for people to be labeled at inadequent in mental stability when the thyroid ( or not having one) isreally the problem.
If you google up iodine and Free T3 hormone you will see a direct link to low functioning or non thyroid individuals and a connection on mental stability with this condition.
I was born without a thryoid~they found it in my blood work when I was 6 weeks old and put me on medication for it as soon as they could
I have learning disabilites as well as I suffer from bipolar disorder and aniexty
If my medication is out of wack then my depression and aniextyy is out of wack as well