OCD

Question 1

what is the main approach used to explain OCD?

Answer 1

biological

Question 2

what is OCD?

Answer 2

an anxiety disorder characterised by persistent, recurrent, unpleasant thoughts and repetitive, ritualistic behaviours

Question 3

what are obsessions?

Answer 3

-things people think about
-forbidden/inappropriate ideas and images that aren’t based on reality

Question 4

what are compulsions?

Answer 4

-things people do as a result of obsessions
-urges to repetitively perform tasks and behaviours
-attempt to reduce distress/ prevent feared events
-avoiding situations that trigger obsessive ideas/images

Question 5

what are the statistics of ocd sufferers?

Answer 5

-less than 2% of the population
-no gender differences in prevalence, but there are gender differences in the types of ocd suffered (Females are more focused on cleaning and contamination, while men have more religious and sexual obsessions)
-males tend to have an earlier gradual onset with more severe symptoms, females have later sudden onset with fewer severe symptoms

Question 6

what are the behavioural symptoms of obsessions?

Answer 6

-hinder everyday functioning
-social impairment

Question 7

what are the emotional symptoms of obsessions?

Answer 7

-extreme anxiety

Question 8

what are the cognitive symptoms of obsessions?

Answer 8

-recurrent and persistent thoughts
-recognised as self-generated
-realisation of inappropriateness
-attentional bias

Question 9

what are common obsessions?

Answer 9

-contamination
-fear of losing control
-perfectionism
-religion

Question 10

what are the behavioural symptoms of compulsions?

Answer 10

-repetitive behaviours
-hinder everyday functioning
-social impairment

Question 11

what are the emotional symptoms of compulsions?

Answer 11

-distress

Question 12

what are the cognitive symptoms of compulsions?

Answer 12

-uncontrollable urges
-realisation of inappropriateness

Question 13

what are common compulsions?

Answer 13

-excessive washing/cleaning
-excessive checking
-repetition
-mental compulsions eg praying to prevent harm
-hoarding

Question 14

what are the two ways of explaining OCD?

Answer 14

genetic explanations
neural explanations

Question 15

how do genetics explain OCD?

Answer 15

-inherited through genetic transmission
-gene-mapping studies used to compare the genetic material of OCD sufferers to non-sufferers

Question 16

is it more likely a single gene or combination causes OCD?

Answer 16

combination, can determine vulnerability

Question 17

what was grootheest, cath, beekman and boomsma’s 2005 research on OCD?

Answer 17

-reviewed twin studies
-2 types of studies:
-‘old literature’ - between 1929 - 65
-‘studies meeting modern criteria’ - patients diagnosed under DSM criteria
-genetic influence ranged from 45-65% in children, 27-47% in adults
-indicated heritability
-studies weren’t properly controlled
-need to assess whether the sub-types of OCD have different levels of genetic transmission

Question 18

research on the genetic explanation

Answer 18

-samuels et al 2007 - used gene mapping to compare OCD sufferers to non sufferers, finding a link to chromosome 14 marker D14S588, implying genetic influence is correct
-davis et al 2013 - used genome-wide complex trait analysis, which simultaneously compares the whole genome, not singular genes, used 1500 OCD p’s and 5500 non-OCD (also 1500 tourettes vs 5200 non-tourettes), showed both had a genetic basis, and although they had shared genetic characteristics, they had distinct genetic architectures

Question 19

evaluate the genetic explanation

Answer 19

-must be some environmental influences or else concordance rates between MZ twins would be 100%
-doesn’t appear to be a lone gene in transmission, seems to be many genes that contribute to a person’s risk of developing it, which will then depend on environment
-pato et al 2001 - altho research shows heritability, few details are understood abt the genetic mechanisms underpinning the disorder
-the fact some develops in childhood while others develop in adulthood supports the idea that some forms are more genetic
-compulsions are different within the fam, eg kid lining up dolls vs mother washing constantly, if it was genetic wouldn’t it be the same type?

Question 20

what is the neural explanation of OCD?

Answer 20

-breakdowns in the immune system through throat infections, flu and lymes disease damages neural mechanisms
-PET scans show low levels of serotonin activity in brains of OCD p’s, and drugs that increase serotonin have decreased symptoms

Question 21

what brain area is linked to the neural explanation of OCD?

Answer 21

-PET scans show higher activity in the orbital frontal cortex of OCD sufferers (brain area associated with higher-level thought processes and the conversion of sensory info into thoughts)
-initiates activity upon receiving impulses to act, and stopping the activity when the impulses lessen

Question 22

research on the neural explanation

Answer 22

-fallon + nields 1994 - 40% of people contracting lymes disease incur neural damage resulting in psychiatric conditions including OCD
-zohar et al 1987 - gave mCPP (serotonin reduction drug) to 12 OCD p’s and 20 non-OCD p’s, finding symptoms were significantly enhanced in OCD sufferers

Question 23

evaluate the neural explanation

Answer 23

-its thought infections that reduce immune system functioning don’t cause OCD, but trigger symptoms in those that are genetically vulnerable
-the extent of involvement of serotonin and orbital frontal cortex as causes and not effects hasn’t been established
-may be a genetic connection to neural mechanisms, NIMH study examined DNA samples of sufferers, found OCD was associated with 2 mutations of the human serotonin transporter gene (hSERT), causing lower levels
-still not known how the neural differences relate to the precise mechanisms of OCD
-not all sufferers respond well to serotonin enhancing drugs, lessening support

Question 24

what are the 2 other minor explanations for OCD?

Answer 24

-evolutionary
-cognitive

Question 25

what is the evolutionary explanation for OCD?

Answer 25

-has an adaptive survival value eg washing to prevent infection, hoarding for hunting
-chepko-sade et al 1989 - rhesus monkeys that groomed others the most were retained in a group following fights, suggesting their tendencies had a survival value
-can be seen as an extension of the genetic explanation, as genes cause evolution
-behavioural features of OCD would have been useful in the EEA, and remain now due to genome lag, where genes take time to adapt to their current environment

Question 26

what is the cognitive explanation for OCD?

Answer 26

-fault-persistent thought processes, focusing on anxiety-generating stimuli
-rachman + hodges 1987 - some are more susceptible to obsessional thinking bcs of increased vulnerability due to genetics
-faulty thought processes could be due to having impaired neural functions, allowing cog explanation to be put into a biological framework, rather than a separate explanation
-the fact there are different forms of OCD focusing on different anxiety-generating stimuli promotes cognitive explanation