biological approach to explaining OCD

Question 1

Szechman et al

Answer 1

high doses of dopamine given to animals which induced OCD-like movements. Supports biochemical explanation.

Question 2

Pigott et al

Answer 2

antidepressants increase serotonin which reduces OCD symptoms. Suggests low serotonin causes OCD. Support for biochemical explanation.

Question 3

Tukel et al

Answer 3

COMT gene regulated dopamine. Lower activity version causes OCD.

Question 4

Ozkai et al

Answer 4

SERT gene codes for enzymes involved in serotonin transport. OCD form results in low serotonin. Found mutation of SERT gene in 2 unrelated families where most members had OCD.

Question 5

Nestadt et al

Answer 5

first degree relatives with OCD had greater risk of developing it themselves. Support for genetic explanation.

Question 6

Cromer et al

Answer 6

half OCD patients had traumatic event in past. Other explanations for biological explanation.

Question 7

Menzies et al

Answer 7

MRI scans of OCD patients. Grey matter in key regions such as OFC. Support for biological structures.