OCD

OCD diagnosis

A. Presence of obsessions, compulsions, or both: 5

• Obsessions are defined by (1) and (2):

• 1. Recurrent and persistent thoughts, urges, or impulses -- intrusive

and unwanted, most individuals cause marked anxiety or distress.

• 2.The individual attempts to ignore or suppress such thoughts,

urges, or images, or to neutralize them with some other thought or

action

• Compulsions are defined by (1) and (2):

• 1. Repetitive behaviors or mental acts that the individual feels driven

to perform in response to an obsession or according to rules that

must be applied rigidly

• 2.The behaviors or mental acts are aimed at preventing or reducing

anxiety or distress, or preventing some dreaded event or situation

B. The obsessions or compulsions are time-consuming (e.g., take more

than 1 hour per day) or cause clinically significant distress or

impairment in social, occupational, or other important areas of

functioning

What is obsession

Regular, intrusive thought that cause anxiety/distress

What is compulsion

Drive to perform rituals to alleviate obsession

Contamination dimension obsession and compulsion

Obsession: concern about dirt and germ

Compulsion: washing/showering/cleaning

Harm dimension obsession and compulsion

Obsession: concern about getting hurt

Compulsion: checking

Unacceptability dimension obsession and compulsion

Obsession: intrusive aggressive, sexual or religious thought

Compulsion: mental ritual/praying

Symmetry dimension obsession and compulsion

Obsession: concern about symmetry

Compulsion: ordering, straighening, repeating, counting

Hoarding dimension obsession and compulsion

Obsession: concern about hoarding

Compulsion: hoarding behavior

OCD with good insight

Knows OCD belief is not true or may or may not be true

OCD with poor insight

Think that OCD belief are probably true

OCD with absent/delusional belief

Thinks OCD beliefs are definitely true

OCD and related disorders

OCD, body dysmorphic disorder, trichotillomania (hair pulling), hoarding, excoriation (skin picking), Tourette, hypochondriasis, olfactory reference

OCD coexist with what other conditions

ADHD, tic disorders, stereotypic movement disorder

CSTC circuits relation to OCD early phase

Dorsal, ventral cognitive and ventral reward CSTC + frontolimbic more active

CSTC circuits relation to OCD late phase

Sensorimotor, dorsal and ventral cognitive CSTC involvement → causes compulsions

Molecular mechanism of OCD

Dopamine → causes stereotypic behavior; decreased D2 in striatum

Glutaminergic neuron relate to CSTC