OCD

Question 1

Obsessions

Answer 1

Internal components of recurring intrusive thoughts or impulses that may be inappropriate

Question 2

Compulsions

Answer 2

External component of repetitive behaviours or mental acts done to reduce anxiety caused by obsessions and feelings that something bad will happen if they don’t

Question 3

Emotional characteristics of OCD

Answer 3

Anxiety - caused by obsessions and compulsions
Guilt and disgust - because aware their behaviour is excessive

Question 4

Behavioural characteristics of OCD

Answer 4

Compulsions
Avoidance - of situations that will trigger their anxiety

Question 5

Cognitive characteristics of OCD

Answer 5

Obsessions
Insight - know their obsessions and compulsions are irrational but can’t help it

Question 6

Polygenic

Answer 6

Caused by many genes

Question 7

How many genes may cause OCD (Taylor)?

Answer 7

Up to 230

Question 8

How do genes lead to OCD?

Answer 8

They predispose the individual to OCD so if in right environment, it can develop

Question 9

Aetiologically heterogenous

Answer 9

Origin of OCD has different causes and different groups of genes may cause OCD in different people, or cause different types of OCD

Question 10

SERT gene

Answer 10

Serotonin transporter

Question 11

What is the result of a mutated SERT gene in people with OCD?

Answer 11

Caused and increase in transporter proteins in the neuron’s membrane so there is an increase in reputase of serotonin into the neuron, decreasing levels of serotonin in the synapse

Question 12

Serotonin

Answer 12

Happy hormone

Question 13

COMT gene

Answer 13

Catechol-O-Methyl Transferase
Instructs an enzyme to break down neurotransmitters in the synapse

Question 14

Dopamine

Answer 14

Reward hormone
connects feelings of pleasure to certain behaviours

Question 15

effect of mutated COMT gene

Answer 15

causes decrease in COMT activity resulting in increased levels of dopamine

Question 16

genetic explanation for OCD evaluation

Answer 16

relative environment of twin concordance is stressful

Question 17

what is the “abnormal levels of neurotransmitters” explanation of OCD

Answer 17

low levels of serotonin mean mood-relevant information isn’t properly transmitted so mood and sometimes other mental processes are affected

Question 18

what is the “abnormal brain circuits” explanation for OCD?

Answer 18

the caudate nucleus is damaged, so fails to supress minor worries from the OFC, and instead the thalami is alerted, which sends signals back to the OFC, acting as a worry circuit

Question 19

Neural explanations of OCD evaluation

Answer 19

serotonin is a consequence of depressed associations and damage

Question 20

OFC

Answer 20

Orbitofrontal cortex

Question 21

where is the caudate nucleus?

Answer 21

in the basal ganglia

Question 22

SSRI

Answer 22

selective serotonin reuptake inhibitor

Question 23

what do SSRI’s do?

Answer 23

block the reuptake of serotonin in the brain so it remains active at the synapse where it continues to stimulate the post-synaptic neuron, reducing the symptoms of anxiety

Question 24

what may be done if SSRIs are not effective after 3-4 months?

Answer 24

the dosage may be increased, it may be used in conjunction with CBT or a different antidepressant may be used

Question 25

tricyclics action

Answer 25

block the transporter mechanism for both serotonin and noradrenaline into the presynaptic neuron after it has fired

Question 26

what is the downside of tricyclics?

Answer 26

they generally have more side effects than SSRIs

Question 27

Benzodiazepines

Answer 27

anti-anxiety drugs –> slow activity of CNS by enhancing activity of GABA

Question 28

GABA action

Answer 28

locks onto receptor sites outside neuron
opens channel allowing chloride ions to flow into the neuron
make it harder for the neuron to be stimulated by other neurotransmitters
slows it’s activity and produces calming effect

Question 29

Drug therapy for OCD evaluation

Answer 29

effective relapsing of cheap side effects working together

Question 30

Who did the twin study that supports the genetic explanation of OCD

Answer 30

Nestadt

Question 31

Nestadt figures

Answer 31

68% MZ concordance
31% DZ concordance

Question 32

Lewis findings (OCD)

Answer 32

37% had parents with OCD and 21% had siblings with OCD

Question 33

what is the low levels of neurotransmitter explanation for OCD based on?

Answer 33

The findings that OCD can be relieved by anti-depressants, especially those that increase levels of serotonin in the brain

Question 34

Zohar et al. findings

Answer 34

drugs that increased levels of serotonin in OCD patients benefitted 60% of patientsc

Question 35

challenge of Zohar et al. findings

Answer 35

most drug treatment studies have only found 50% improvement in OCD patients suggesting other factors involved.

Question 36

what did MacGuire et al. find?

Answer 36

brain imaging studies indicate brain regions such as the OFC and caudate nucleus are associated with OCD

Question 37

Soomro et al. findings

Answer 37

reviewed 17 studies in the use of SSRIs and found them to be more effective than placebos in reducing OCD symptoms up to 3 months after treatment, in the ST

Question 38

what is the % range of OCD patients that get no benefit from SSRIs?

Answer 38

30-50%

Question 39

relapse rates for OCD

Answer 39

90%