psychopathology - ocd biological approach

Question 1

what is one form of biological explanation for OCD

Answer 1

the genetic explanation

Genes are involved in vulnerability to OCD.

Question 2

who observed OCD patients

Answer 2

Lewis (1936)

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

Question 3

what did lewis study suggest

Answer 3

genetic vulnerability to OCD runs in families

Question 4

what dose the diathesis stress model say about OCD

Answer 4

certain genes leave some people more likely to develop a mental disorder

Environmental stress needed to trigger this.

Question 5

what are candidate genes

Answer 5

specific genes which create a vulnerability for OCD,

Question 6

one example of a candidate gene for OCD

Answer 6

serotonin genes - implicated in the transmission of serotonin across synapses (NEUROTRANSMITTER)

Dopamine genes

Question 7

what dose the genetic explanation say OCD is

Answer 7

polygenetic

Question 8

who study polygenetic genes in OCD

Answer 8

Taylor (2013)

up to 230 different genes may be involved in OCD.

Question 9

Describe different types of OCD

Answer 9

aetiologically heterogeneous, meaning that the origins of OCD vary from one person to another.

Question 10

STRENGTH OF THE Genetic explanation

Answer 10

strong evidence base

Nestadt et al. reviewed twin studies
found that 68% of identical twins (MZ) shared OCD
31% of non-identical twins (DZ).

Marini and Stebnicki - person with a family member with OCD is around four times as likely to develop it as someone without.

people who are genetically similar are more likely to share OCD, supporting a role for genetic vulnerability.

Question 11

LIMITATION OF THE genetic explanation

Answer 11

existence of environmental risk factors.

environmental risk factors that trigger or increase the risk of OCD.

Cromer et al. (2007) - one sample over half of people with OCD experienced a traumatic event. OCD severely correlated positively with a number of traumas.

Question 12

describe the role of seretonin in OCD

Answer 12

believed to help regulate mood.

responsible for relaying information from one neuron to another. (The Basal Ganglia to the obitolfrontal cortex to motor area.)

Question 13

what happens if a person has low seretonin

Answer 13

normal transmission of mood-relevant information does not take place, mood is affected

ocd - explained by a reduction in the functioning of the serotonin system in the brain.

Question 14

how dose the decision making process work

Answer 14

associated with abnormal functioning of the lateral (side bits) frontal lobes of the brain.

frontal lobes are responsible for logical thinking and decision making.

Question 15

strength of the neural model of OCD

Answer 15

supporting evidence

Antidepressants that work on serotonin reduce OCD symptoms. This suggests that serotonin may be involved on OCD.

OCD symptoms form part of conditions that are known to be biological in origin, such as Parkinson’s disease

Question 16

limitation of the neural model

Answer 16

does not necessarily mean causality.

The biological model suggests this is explained by brain dysfunction causing the OCD.

just a correlation which does not necessarily indicate a causal relationship. OCD might cause the abnormal brain function.