Causes
#OCD and Learned Behaviour: derieved from Mawrer's two process theory of
avoidance learning. Neutral stimuli become associated with frightening thoughts or
experiences through classical conditioning and come to elicit anxiety. Once having
made this association, the person may discover that the anxiety can be reduced by
da specific behavior. Doing this ritual just makes it stronger and very resistant to
extinction.
#Preparedness: evolutionary context of fears may be adaptive to our early ancestors.
For example: fear of contamination. The same behavior is visible also in animals.
#Cognitiva casual factors:
. Attempting to suppresshe effects of attempting to suppress obsessive thoughtsT##
thoughts can paradoxically increase them. People with normal and abnormal
obsessions differ primary in the degree to which they resist their own
thoughts and find them acceptable. OCD patients indeed do it much more
than normal people although it is not affective.
. Inflated scence of responsibility.Appraisals of responsibility for intrusive thoughts##
Beliefs that simply having a thought about doing something is morally
equivalent to actually doing it. "Thought-action fusion".
their attention is drawn to disturbing material-Cognitive Biases and distortions##
relevant to their obsessive concerns- like in other anxiety disorders. They
have difficulty in blocking out negative irrelevant input or distracting
information, so they attempt to suppress these thoughts.
#Biological factors:
: Twin studies: high concordance rate for monozygotic twins and aGenetic Factors##
lower one for dizygotic twins. Family studies: 3 to 12 times higher rates of
OCD in first degree relatives.
One type of OCD- starts in childhood and is characterized by chronic motor
tics is strongly linked to Tourette syndrome.
Moreover- molecular genetic studies: different genetic polymorphism
(naturally occurring variations).
: Abnormalities occur primarily in certain cortical structures asOCD and the Brain##
Which is linkedBasal Ganglia.well as in certain subcortical structures as the
at the amygdala to the limbic system which controles emotional behavior.
Pet scans show high abnormal activity in two parts of prefrontal cortex:
orbital frontal cortex and the cingulate cortex. Also high activity in caudate
nucleus and basal ganglia. These primitive structures are involved in
executing primitive patterns of behavior: sex agressuin and hygene concerns.
Primitive thoughts in orbital frontal cortex filtered by caudate nucleus
allowing only the strongest ones to pass to the thalamus. This circuit is
responsible for behavioral responses.
: Clomipramine affects neurotransmitter serotoninNeurotransmitter abnormalities##
which is strongly implicated with OCD. Also, other drugs from the SSRi family.
Increased serotonin activity and increased sensitivity of some brain structures to
serotonin are involved in OCD symptoms. Clomipramine- at first increases
serotonin and then lowers it. Its also becoming clear that dysfunction in
serotonin is not enough to explain OCD. It can be also dopaminergic, GABA
and glutamate systems.
Treatments
#Exposure and response prevention: involves having the client develop hierarchy of
upsetting stimuli and rate them from 0 to 100 scale. Then the client is asked to
expose themselves repeatedly so stimuli that will provoke their obsessions.
Following each exposure they are asked to not engage in their rituals. Many drop out
but the ones who stay show 50-70% of reduction of the symptoms. These results
considered superior to medications.
#Family Therapy: Family Accommodation Behaviors are things families do that
enable OCD symptoms. Families are constantly affected by the demands of OCD.
Research shows that how a family responds to the OCD may help fuel OCD
symptoms.
#Medications: Medications that affect the neurotransmitter Serotonin seem to be
the primary class of medication. Anti-depressant drugs as Clomipramine and
fluoxetine (Prozac), which alter functioning of the serotonin system, appear to
reduce the intensity of the symptoms. Those who don't respond to that- a small
whenpsychotic drugs may help. The major disadvantage is:-dosage of anti
Combiningmedication is discontinued, relapse rates are generally very high.
medication with psychological therapy is more helpful than the therapy only..
# Gamma knife radiosurgery is a treatment for OCD that does not require opening
the skull. In gamma knife procedures, multiple gamma rays pass through the skull.
On its own, a single gamma ray poses no danger to brain tissue. However, when
gamma rays intersect, the energy level is high enough to destroy the targeted brain
tissue. The most recent version of this procedure is called gamma ventral
capsulotomy. This is because the procedure is limited to the ventral (bottom) half of
a brain area called the anterior capsule. About 60% of those who did not respond to
behavior therapy or medicines for OCD got some benefit from the procedure.
# Repetitive transcranial magnetic stimulation (rTMS) We tested whether lowfrequency
repetitive transcranial magnetic stimulation (rTMS) could normalize
overactive motor cortical regions and thereby improve symptoms. Suggestions of
clinical improvement were apparent as early as the first week of rTMS.
We report a clinically significant improvement in OCD and TS symptoms with
benefits lasting up to 3 months in almost two thirds of the patients, similarly to that
reported with conventional treatments.
# Deep Brain Stimulation: This intervention is only for individuals who do not
respond well to behavior therapy or medicines for OCD.
What is deep brain stimulation (DBS)?
• DBS has been used since the mid 1980s to treat the symptoms of movement
disorders such as Parkinson’s disease.
• DBS involves placing electrodes in targeted areas of the brain. Once the
electrodes are in place, they are connected by wires under the skin to pulse
generators under the skin (usually just below the collarbone).
# Surgery: Anterior cingulotomy – This is a brain surgery that involves drilling through the
skull and using a heated probe to burn an area within a part of the brain called the anterior
cingulate cortex.
Anterior capsulotomy - This procedure is very similar to the surgery listed above. However,
in this surgery, doctors operate on a different part of the brain, called the anterior limb of
the internal capsule.