Page | 1
A-LEVEL PSYCHOLOGY AQA PAPER 1 2025|
BRAND NEW ACTUAL EXAM WITH 100%
VERIFIED QUESTIONS AND CORRECT
SOLUTIONS| GUARANTEED VALUE PACK| ACE
YOUR GRADES.
Cognitive characteristics of OCD - correct answer - Obsessions -
recurrent, intrusive thoughts or impulses that are perceived as
inappropriate or forbidden. Frightening or embarrassing. Themes
include: ideas (e.g. that germs are everywhere), doubts (e.g. the
worry that something important has been overlooked), impulses
(e.g. to shout out obscenities) or images (e.g. fleeting sexual
images).
Seen as uncontrollable. Person recognises that they are a
product of their own mind.
At some point during the disorder the obsessions or compulsions
are not recognised ad being excessive or unreasonable.
Behavioural characteristics of OCD - correct answer -
Compulsions - May be repetitive or unconcealed acts (such as
hand washing or checking), mental acts (such as praying or
counting). Feel they need to perform these actions. Not
connected in a realistic way with what they are designed to
neutralise. Some people have compulsions without obsessions
(such as compulsively avoiding certain objects)
, Page | 2
Biological approach to explaining OCD - correct answer - Genetic
explanations, neural explanations.
Genetic explanations - correct answer - COMT gene, SERT gene,
Diathesis-stress
COMT gene - correct answer - Regulates the production of
dopamine. Lower activity means higher levels of dopamine.
SERT gene - correct answer - Affects the transport of serotonin,
creating lower levels of this neurotransmitter.
Diathesis-stress - correct answer - Link between genes and
environment, not just genes, environmental 'stressors'
Neural explanations - correct answer - Abnormal levels of
neurotransmitters, abnormal brain circuits
, Page | 3
Abnormal levels of neurotransmitters - correct answer - Dopamine
levels are thought to be abnormally high in people with OCD.
Lower levels of serotonin are associated with OCD.
Abnormal brain circuits - correct answer - Several areas in the
frontal lobes of the brain are thought to be abnormal in people
with OCD.
The caudate nucleus (CN) should suppress signals from the
orbitofrontal cortex (OFC). In turn, the OFC sends signals to the
thalamus about things that are worrying. When the CN is
damaged, it can't supress minor worry signals, so the thalamus is
altered and sends signals back to the OFC, creating response.
> Supported by PET scans.
> Serotonin and dopamine levels are linked tot these areas.
Concordance rate - correct answer - A measure of genetic
similarity
Dopamine - correct answer - One of the key neurotransmitters in
the brain, with effects on motivation and 'drive'.
, Page | 4
Gene - correct answer - A part of a chromosome of an organism
that carries information in the form of DNA.
Neurotransmitter - correct answer - Chemical substances that
play an important part in the workings of the nervous system by
transmitting nerve impulses across a synapse.
Evaluation of biological approach to explaining OCD - correct
answer - Family and twin studies - high concordance, Billet et al
(1998)
Tourette's syndrome and other disorders - Pauls and Leckman
(1986)
Research support for genes and OFC - Menzies et al (2007)
Alternative explanation - two-process model can be applied.
Billet et al - correct answer - 1998. Meta-analysis. On average MZ
twins were more than twice as likely to develop OCD if their co-
twin had the disorder than was the case for DZ twins.
Menzies et al - correct answer - 2007. Used MRI to produce
images of brain activity in OCD patients and their immediate
family members without OCD and also a group of unrelated
A-LEVEL PSYCHOLOGY AQA PAPER 1 2025|
BRAND NEW ACTUAL EXAM WITH 100%
VERIFIED QUESTIONS AND CORRECT
SOLUTIONS| GUARANTEED VALUE PACK| ACE
YOUR GRADES.
Cognitive characteristics of OCD - correct answer - Obsessions -
recurrent, intrusive thoughts or impulses that are perceived as
inappropriate or forbidden. Frightening or embarrassing. Themes
include: ideas (e.g. that germs are everywhere), doubts (e.g. the
worry that something important has been overlooked), impulses
(e.g. to shout out obscenities) or images (e.g. fleeting sexual
images).
Seen as uncontrollable. Person recognises that they are a
product of their own mind.
At some point during the disorder the obsessions or compulsions
are not recognised ad being excessive or unreasonable.
Behavioural characteristics of OCD - correct answer -
Compulsions - May be repetitive or unconcealed acts (such as
hand washing or checking), mental acts (such as praying or
counting). Feel they need to perform these actions. Not
connected in a realistic way with what they are designed to
neutralise. Some people have compulsions without obsessions
(such as compulsively avoiding certain objects)
, Page | 2
Biological approach to explaining OCD - correct answer - Genetic
explanations, neural explanations.
Genetic explanations - correct answer - COMT gene, SERT gene,
Diathesis-stress
COMT gene - correct answer - Regulates the production of
dopamine. Lower activity means higher levels of dopamine.
SERT gene - correct answer - Affects the transport of serotonin,
creating lower levels of this neurotransmitter.
Diathesis-stress - correct answer - Link between genes and
environment, not just genes, environmental 'stressors'
Neural explanations - correct answer - Abnormal levels of
neurotransmitters, abnormal brain circuits
, Page | 3
Abnormal levels of neurotransmitters - correct answer - Dopamine
levels are thought to be abnormally high in people with OCD.
Lower levels of serotonin are associated with OCD.
Abnormal brain circuits - correct answer - Several areas in the
frontal lobes of the brain are thought to be abnormal in people
with OCD.
The caudate nucleus (CN) should suppress signals from the
orbitofrontal cortex (OFC). In turn, the OFC sends signals to the
thalamus about things that are worrying. When the CN is
damaged, it can't supress minor worry signals, so the thalamus is
altered and sends signals back to the OFC, creating response.
> Supported by PET scans.
> Serotonin and dopamine levels are linked tot these areas.
Concordance rate - correct answer - A measure of genetic
similarity
Dopamine - correct answer - One of the key neurotransmitters in
the brain, with effects on motivation and 'drive'.
, Page | 4
Gene - correct answer - A part of a chromosome of an organism
that carries information in the form of DNA.
Neurotransmitter - correct answer - Chemical substances that
play an important part in the workings of the nervous system by
transmitting nerve impulses across a synapse.
Evaluation of biological approach to explaining OCD - correct
answer - Family and twin studies - high concordance, Billet et al
(1998)
Tourette's syndrome and other disorders - Pauls and Leckman
(1986)
Research support for genes and OFC - Menzies et al (2007)
Alternative explanation - two-process model can be applied.
Billet et al - correct answer - 1998. Meta-analysis. On average MZ
twins were more than twice as likely to develop OCD if their co-
twin had the disorder than was the case for DZ twins.
Menzies et al - correct answer - 2007. Used MRI to produce
images of brain activity in OCD patients and their immediate
family members without OCD and also a group of unrelated
