By David Tolin, Ph.D., ABPP Intrusive thoughts are a common human experience, yet they take distinct forms that differ in structure, function, and clinical significance. Three of the most frequently discussed types are obsessions, worry, and rumination. Although they share features—repetitiveness, perceived uncontrollability, and cognitive intrusiveness—their underlying processes and diagnostic implications diverge in meaningful ways. Obsessions, as defined in obsessive‑co

While children understand and experience OCD differently than adults, they benefit from similar kinds of treatments.