Transcript OCD - UCSD Cognitive Science

Obsessive Compulsive
Disorder
Features of OCD
• Obsessions
– Recurrent and persistent thoughts; impulses; or
images of violence, contamination, and the like
– intrusive and distressing
– Individual tries to ignore, suppress, or neutralize
• Compulsions
– Repetitive behaviors individual feels driven to perform
– Ritualistic/need to follow a set of rules
– Intended to prevent or reduce distress or some
dreaded event
DSMIV
• See webpage:
• http://anxiety.psy.ohio-state.edu/ocd1.htm
OCD Features
• Data from the Epidemiological Catchment Area
•
•
(ECA) survey found a 6-month point prevalence
of 1.6% and a lifetime prevalence of 2.5% in the
general population
Sex ratio is 1:1.1 (men to women)
Mean age of onset is 20.9 years (SD=9.6)
– Males is 19.5 years (SD = 9.2)
– Females is 22.0 years (SD = 9.8)
• Most develop their illness before the age of 25
• Symptoms can be remembered as far back as
the onset of puberty.
Comorbidity
• Major depression is the most common comorbid
disorder
– 1/3 have concurrent MDD
– 2/3 have a lifetime history of MDD
• Other Axis I disorders include panic disorder
•
with agoraphobia, social phobia, generalized
anxiety disorder, Tourette’s syndrome,
trichotillomania, schizophrenia
Axis I comorbid disorders can effect the severity
and treatment of OCD.
Comorbidity
• Obsessive-compulsive personality disorder
(OCPD) is an Axis II disorder. OCPD differs
from OCD by the lack of true obsessions
and compulsions.
More features
• Types of Obsessions
– Aggressive obsessions
– Contamination obsessions
– Sexual obsessions
– Hoarding/saving obsessions
– Religious obsessions
– Symmetry/exactness
– Somatic obsessions
• Types of compulsions
– Cleaning/washing compulsions
– Checking compulsions
– Repeating rituals
– Counting compulsions
– Ordering/arranging
– Hoarding/collecting
– Mental rituals
IS OCD Experienced by the Normal
Population??
• Most people experience intrusive thoughts
throughout their life
• Individuals who develop OCD may react
more negatively to their intrusions
Neurobiology/physiology
• No chronic hyperarousal
• Over activation of the orbitofrontal cortex
(thought generation) and under activation
of the caudate nuclei (thought
suppression)
Psychosocial
• Learning
– Animal models
• High stress or repeated frustration leads to
increase in ritualistic-like behaviors
• Fixed action pattern- innate and adaptive
behavioral sequences to specific stimuli
– Biological preparedness
• Washing and checking may have once promoted
survival
• Cognitive deficits
– Increased attention allocated to fear related
stimuli
– Tend to encode negative stimuli more indepth
than neutral and positive stimuli, leading to
better memory for negative stimuli
– Overattention to detail
Cognitive theory of OCD
• Obsessional thoughts:
– If obsessions occur frequently in normal populations,
why don’t most people suffer from OCD?
– It’s not the thought itself that is disturbing, but rather
the interpretation of the thought.
• Example: having an unacceptable sexual thought leads to
beliefs that the person is depraved, perverted, abnormal,
evil, etc…., which leads to affective states such as anxiety
and depression.
– The issue of responsibility is believed to be a core
belief or cognitive distortion of people with OCD.
– There are three main consequences of
neutralizing behavior
• It results in reduced discomfort, which leads to
the development of compulsive behavior as a
tool for dealing with stress. This reinforcing
behavior may result in a generalization of this
strategy
• Neutralizing will be followed by nonpunishment, and can lead to an effect on the
perceived validity of the beliefs (NAT)
• The neutralizing behavior itself becomes a
powerful and unavoidable triggering stimulus.
The neutralizing behavior serves to reinforce
the belief that something bad may happen
Pharmacotherapy
• Serotonin (5-HT) neurotransmission
abnormalities have been implicated in the
pathophysiology and treatment
• Antidepressant medications of the
Serotonin Reuptake Inhibitor classification
and specific tricyclic antidepressants
(Clomipramine) have been proven to be
effective in the treatment of OCD
• Currently there are 6 SSRIs that are
FDA approved for the treatment of OCD
– Clomipramine (Anafranil)
– Fluoxetine (Prozac)
– Fluvoxamine (Luvox)
– Paroxetine (Paxil)
– Sertraline (Zoloft)
– Citalopran (Celexa)
– See Graybiel article for hypotheses
regarding neural etiology of disease state!!