A study has found people with obsessive compulsive disorder (OCD) often find that their intrusive thoughts come along with "sensory experiences" — quasi-hallucinations that attach some physical sensation to the distorted thinking the disorder can produce.

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A study has found people with obsessive compulsive disorder (OCD) often find that their intrusive thoughts come along with "sensory experiences" — quasi-hallucinations that attach some physical sensation to the distorted thinking the disorder can produce.