AQA GCSE Psychology: Brain and Neuropsychology and Psychological Problems Revision Guide

Brain and Neuropsychology and Psychological Problems are two of the four topics examined on Paper 2 of AQA GCSE Psychology (8182). Together they cover some of the most scientifically grounded material on the specification -- from how neurons transmit signals and how scanning technology maps brain activity, through to the biological and psychological explanations for depression and addiction. Students who master these topics are well placed to pick up marks across the full range of question types, including extended-response evaluation questions that carry the highest tariffs.

This guide works through every sub-topic you need to know for the exam, explains the key theories and studies, and highlights how examiners expect you to present your answers.

Where These Topics Sit in the Exam

AQA GCSE Psychology is assessed through two written papers, each worth 50% of your final grade.

Paper 1: Cognition and Behaviour -- 1 hour 45 minutes, 100 marks. Covers Memory, Perception, Development, and Research Methods.

Paper 2: Social Context and Behaviour -- 1 hour 45 minutes, 100 marks. Covers Social Influence, Language Thought and Communication, Brain and Neuropsychology, and Psychological Problems.

Brain and Neuropsychology and Psychological Problems both appear on Paper 2. Each topic will have its own section of questions, typically progressing from short-answer recall (AO1) through application (AO2) to extended evaluation (AO3). You should expect a mix of multiple-choice, short-answer, and longer 6-mark or 9-mark questions across these sections.

For a broader look at exam technique across both papers, see the AQA GCSE Psychology Exam Guide.

Part 1: Brain and Neuropsychology

The Nervous System

The nervous system is the body's communication network. It is divided into two main parts.

The central nervous system (CNS) consists of the brain and the spinal cord. The brain is the control centre, processing information and coordinating responses. The spinal cord connects the brain to the rest of the body and handles some automatic responses (reflex arcs) without waiting for the brain to process information.

The peripheral nervous system (PNS) is everything outside the CNS -- the network of nerves running throughout the body. It is subdivided into two branches:

The somatic nervous system controls voluntary movements. When you decide to pick up a pen, the somatic nervous system carries signals from the brain to the muscles in your hand.
The autonomic nervous system controls involuntary processes such as heart rate, digestion, and breathing. It operates without conscious effort and is further divided into the sympathetic branch (which activates the fight-or-flight response) and the parasympathetic branch (which calms the body down after the threat has passed).

An exam question may ask you to identify the two divisions of the PNS or to explain the difference between voluntary and involuntary actions. Make sure you can give clear, concise definitions of each component.

The Structure of the Brain

The brain itself has several distinct regions, each responsible for different functions.

The cerebral cortex is the outer layer of the brain, responsible for higher-level functions such as thinking, language, and planning. It is divided into four lobes:

Frontal lobe -- located at the front of the brain. Responsible for higher cognitive functions including reasoning, planning, decision-making, and personality. It also contains the motor cortex, which controls voluntary movement.
Temporal lobe -- located at the sides of the brain, roughly behind the ears. Responsible for processing auditory information (hearing), language comprehension, and memory formation.
Parietal lobe -- located at the top of the brain towards the back. Responsible for processing sensory information such as touch, temperature, and spatial awareness. It integrates information from different senses to build a coherent understanding of the environment.
Occipital lobe -- located at the very back of the brain. Responsible for processing visual information. Damage to the occipital lobe can cause visual impairments even if the eyes are functioning normally.

The cerebellum sits beneath the cerebral cortex at the back of the brain. It is responsible for coordinating fine motor movements, balance, and posture. It does not initiate movement but ensures that movements are smooth and accurate. Activities such as riding a bicycle or playing an instrument rely heavily on the cerebellum.

The brain stem connects the brain to the spinal cord and controls basic life-sustaining functions such as breathing, heart rate, and sleep-wake cycles. It is sometimes called the "primitive" brain because these functions are essential for survival and operate automatically.

Neurons and Synaptic Transmission

Neurons are specialised cells that transmit electrical and chemical signals throughout the nervous system. There are three types you need to know.

Sensory neurons carry signals from sense organs (such as the eyes, ears, and skin) to the CNS. They convert external stimuli into nerve impulses.

Relay neurons are found within the CNS. They connect sensory neurons to motor neurons and play a key role in processing information. In a reflex arc, the relay neuron in the spinal cord connects the incoming sensory signal directly to the outgoing motor signal, which is why reflexes happen so quickly.

Motor neurons carry signals from the CNS to effectors -- muscles and glands -- causing a response. When a motor neuron sends a signal to a muscle, the muscle contracts.

Synaptic transmission is the process by which signals pass from one neuron to the next. Neurons do not physically touch each other. Instead, there is a tiny gap between them called a synapse. When an electrical impulse reaches the end of a neuron (the synaptic knob), it triggers the release of chemical messengers called neurotransmitters into the synaptic gap. These neurotransmitters cross the gap and bind to receptors on the next neuron, triggering a new electrical impulse. If the neurotransmitter does not match the receptor (like a wrong key in a lock), the signal will not be passed on.

This process is critical to understanding how the brain works and is also the basis for understanding how some drug treatments for psychological problems operate -- for example, SSRIs work by altering neurotransmitter levels at the synapse.

Hebb's Theory of Learning and Neuronal Growth

Donald Hebb proposed that learning occurs when neurons are repeatedly activated together. His theory is often summarised as "neurons that fire together wire together." When two neurons are activated at the same time, the connection (synapse) between them is strengthened. The more frequently this happens, the stronger the neural pathway becomes, making the signal more efficient.

This explains how practice and repetition improve skills and recall. When you revise a topic repeatedly, the neural pathways associated with that knowledge are reinforced, making retrieval faster and more reliable. Conversely, neural pathways that are not used regularly become weaker over time -- this aligns with the idea of "use it or lose it."

Hebb's theory has been supported by modern neuroscience research showing that synaptic connections do physically change with experience, a process known as neuroplasticity. This is a useful evaluation point in the exam -- you can argue that biological evidence supports Hebb's theory, giving it scientific credibility.

Neurological Damage: The Case of Phineas Gage

The effects of brain damage on behaviour provide some of the most compelling evidence for brain localisation -- the idea that different areas of the brain are responsible for different functions.

The most famous case study in this area is Phineas Gage. In 1848, Gage was a railroad construction foreman who survived a severe accident in which a large iron rod was driven through his skull, passing through his left frontal lobe. Remarkably, Gage survived and could still walk, talk, and perform many physical tasks. However, his personality changed dramatically. Before the accident he was described as responsible, reliable, and well-liked. After the accident he became impulsive, rude, and unable to plan or make good decisions. His friends said he was "no longer Gage."

This case is significant because it demonstrated that the frontal lobe is involved in personality, decision-making, and social behaviour. It provided early evidence for the localisation of brain function.

However, the case has limitations. It is a case study of a single individual, so the findings cannot be generalised to everyone. The evidence about Gage's personality changes comes largely from anecdotal reports, not systematic psychological testing. Some historical accounts may have exaggerated the extent of his changes. Despite these limitations, the case of Phineas Gage remains a landmark in neuropsychology.

Brain Scanning Techniques

Modern neuroscience uses several technologies to study the living brain. You need to know three techniques for AQA GCSE Psychology.

CT scans (computerised tomography) use X-rays taken from multiple angles to produce cross-sectional images of the brain. They are useful for detecting structural abnormalities such as tumours, blood clots, and brain damage. CT scans are relatively quick, widely available, and cheaper than other scanning methods. However, they only show brain structure, not brain activity, and they expose patients to a small dose of radiation.

PET scans (positron emission tomography) detect brain activity by tracking the movement of a radioactive tracer (usually glucose) injected into the bloodstream. Active brain areas use more glucose, so they show up more prominently on the scan. PET scans are useful for studying which areas of the brain are active during specific tasks. However, the radioactive tracer means they are slightly invasive, the images have lower spatial resolution than fMRI, and the process is expensive.

fMRI scans (functional magnetic resonance imaging) measure changes in blood oxygenation to detect brain activity. Active areas of the brain require more oxygenated blood, and fMRI detects this difference. fMRI produces high-resolution images of both brain structure and activity without using radiation, making it safer for repeated use. However, fMRI machines are extremely expensive, the scanner is noisy and enclosed (which can cause anxiety), and the images show correlation between brain activity and behaviour rather than proving causation.

When evaluating brain scanning techniques in the exam, a strong approach is to compare two methods -- for example, noting that fMRI provides better spatial resolution than PET but that PET was historically more accessible and could measure neurotransmitter activity directly in some applications.

Key Study in Brain and Neuropsychology

AQA specifies a key study for this topic. Make sure you can describe the aim, procedure, findings, and conclusions of the study, and that you can evaluate it in terms of strengths and limitations. Common evaluation points include the sample size, whether findings can be generalised, the use of scientific methods (brain scanning), and ethical considerations.

Practise writing out the key study under timed conditions. In the exam, you may be asked to describe the study (AO1), apply it to a scenario (AO2), or evaluate its methodology (AO3).

You can test yourself on all of these topics with the AQA GCSE Psychology: Brain and Neuropsychology course.

Part 2: Psychological Problems

Mental Health: An Introduction

A psychological problem -- sometimes called a mental health disorder or mental illness -- is a condition that affects a person's thinking, feelings, or behaviour to such an extent that it causes distress or difficulty functioning in everyday life. Mental health problems are very common. Approximately one in four people in the UK will experience a mental health problem in any given year.

Despite this prevalence, stigma remains a significant barrier to people seeking help. Stigma involves negative attitudes, discrimination, and misunderstanding about mental health conditions. It can lead people to hide their symptoms, avoid treatment, and feel ashamed. Reducing stigma through education and open discussion is an important public health goal.

Effects of Mental Health Problems

Mental health problems affect both individuals and society more broadly.

Effects on individuals include reduced quality of life, difficulty maintaining relationships, problems at work or school, physical health complications (such as disrupted sleep and appetite), and in severe cases, self-harm or suicidal thoughts.

Effects on society include the economic cost of lost productivity, the burden on healthcare services (the NHS spends a significant proportion of its budget on mental health), the strain on families and carers, and the social consequences of untreated mental illness including homelessness and involvement with the criminal justice system.

Characteristics of Clinical Depression

Depression is one of the most common psychological problems. AQA requires you to know its characteristics across three categories.

Emotional characteristics:

Persistent low mood and feelings of sadness
Feelings of worthlessness and low self-esteem
Feelings of hopelessness -- believing things will never improve
Loss of interest or pleasure in activities that were previously enjoyed (anhedonia)

Behavioural characteristics:

Changes in sleep patterns -- insomnia (difficulty sleeping) or hypersomnia (sleeping excessively)
Changes in appetite and weight -- either significant weight loss or weight gain
Reduced activity levels and loss of energy
Social withdrawal -- avoiding friends, family, and social situations
In severe cases, self-harming behaviour

Cognitive characteristics:

Negative thinking patterns -- focusing on the worst in every situation
Poor concentration and difficulty making decisions
Negative self-concept -- a distorted and critical view of oneself
Thoughts about death or suicide

In the exam, you may be asked to identify which category a particular symptom falls into. For example, "poor concentration" is cognitive, not emotional, even though students sometimes confuse the two.

Theories of Depression

Biological explanations propose that depression has a physical cause.

Genetic factors -- research with twins and families suggests that depression runs in families. If one identical twin has depression, the other twin has a significantly higher chance of developing it compared to a non-identical twin. This suggests a genetic vulnerability, although genes alone do not determine whether someone will become depressed.
Neurotransmitter imbalance -- the most widely cited biological explanation focuses on serotonin, a neurotransmitter involved in regulating mood. The theory proposes that low levels of serotonin at the synapse are associated with depression. This explanation is supported by the effectiveness of SSRI antidepressants, which increase serotonin levels. However, critics argue that correlation does not prove causation -- low serotonin may be a symptom of depression rather than its cause.

Psychological explanations propose that depression is caused by patterns of thinking.

Beck's cognitive triad -- Aaron Beck proposed that depression results from three types of negative thinking: a negative view of the self ("I am worthless"), a negative view of the world ("everything is terrible"), and a negative view of the future ("things will never get better"). These three components feed into each other, creating a cycle of negative thinking that maintains the depression. Beck argued that depressed people develop faulty thinking patterns (cognitive distortions) such as overgeneralisation (drawing broad conclusions from a single event) and catastrophising (expecting the worst possible outcome).
Ellis's ABC model -- Albert Ellis proposed that psychological problems arise not from events themselves but from the beliefs people hold about those events. The model has three components: A (Activating event) -- something happens, such as failing an exam; B (Belief) -- the person interprets the event through a rational or irrational belief, for example "I am a complete failure" (irrational) versus "I did not prepare well enough this time" (rational); C (Consequence) -- the belief leads to an emotional and behavioural consequence. Irrational beliefs lead to unhealthy consequences such as depression, while rational beliefs lead to proportionate responses. Ellis argued that challenging and replacing irrational beliefs could alleviate depression.

Treatments for Depression

Antidepressants (SSRIs) -- Selective serotonin reuptake inhibitors are the most commonly prescribed antidepressants. They work by blocking the reabsorption (reuptake) of serotonin at the synapse, leaving more serotonin available to bind to receptors on the next neuron. This increases serotonin activity in the brain and, over several weeks, alleviates symptoms of depression.

Strengths: SSRIs are effective for many people, relatively easy to administer (taken as a daily tablet), and allow patients to function while receiving treatment. They are supported by a large body of clinical research.
Limitations: They can cause side effects such as nausea, headaches, and sleep disturbance. They treat symptoms rather than underlying causes, so depression may return if the medication is stopped. They also take several weeks to become effective, which is problematic for patients in acute distress.

Cognitive behavioural therapy (CBT) -- CBT is a talking therapy based on the idea that thoughts, feelings, and behaviours are interconnected. It draws on Beck's and Ellis's theories. A therapist works with the patient to identify negative or irrational thought patterns and to challenge and replace them with more realistic and balanced alternatives. Patients are also given behavioural tasks (such as scheduling pleasant activities) to break the cycle of withdrawal and low mood.

Strengths: CBT addresses the root cause of depression (faulty thinking) rather than just the symptoms. It teaches skills that patients can continue to use after therapy ends, reducing the risk of relapse. It has no physical side effects, unlike medication. It is recommended by NICE (the National Institute for Health and Care Excellence) as a front-line treatment for depression.
Limitations: CBT requires active participation and motivation from the patient, which can be difficult for someone experiencing severe depression. It is time-consuming (typically 6 to 20 sessions) and access can be limited due to long waiting lists. It may not be suitable for all types of depression -- particularly severe cases where the patient cannot engage with the cognitive work.

Characteristics of Addiction

Addiction is a condition in which a person becomes dependent on a substance or behaviour despite harmful consequences. AQA requires you to understand several key features.

Physical dependence -- the body adapts to the presence of the substance and begins to rely on it to function normally. Without the substance, the person experiences withdrawal symptoms.
Psychological dependence -- a perceived need for the substance or behaviour to cope with stress, feel normal, or experience pleasure. The person may believe they cannot function without it.
Tolerance -- over time, the body becomes less responsive to the substance, meaning the person needs larger doses to achieve the same effect. This can lead to dangerous levels of consumption.
Withdrawal -- when the substance is reduced or stopped, the person experiences unpleasant physical and psychological symptoms such as anxiety, tremors, nausea, and irritability. The discomfort of withdrawal often drives the person to continue using the substance.

Theories of Addiction

Biological explanations:

Genetic vulnerability -- research suggests that some people are more genetically predisposed to addiction than others. Twin studies and family studies show higher rates of addiction among close relatives of addicts, suggesting a heritable component. However, not everyone with a genetic vulnerability develops an addiction, indicating that environmental factors also play a role.
Dopamine reward system -- addictive substances stimulate the release of dopamine in the brain's reward pathway (the mesolimbic pathway). Dopamine produces feelings of pleasure and reinforcement. With repeated use, the brain adapts by reducing its natural dopamine production, meaning the person needs the substance to feel normal. This creates a cycle of dependence.

Psychological explanations:

Positive reinforcement -- the substance produces pleasurable effects (such as euphoria or relaxation), which makes the person more likely to use it again. The behaviour is reinforced because it is associated with a rewarding outcome.
Negative reinforcement -- the substance removes or reduces unpleasant feelings (such as stress, anxiety, or withdrawal symptoms). The relief from discomfort reinforces continued use because the person learns that taking the substance makes them feel better.
Social learning theory -- people may develop addictions by observing and imitating role models (such as parents, peers, or celebrities) who use substances. If the role model appears to be rewarded for their behaviour (for example, seeming more relaxed or confident), the observer is more likely to imitate it. Vicarious reinforcement -- learning from the consequences experienced by others -- is a key mechanism here.

Treatments for Addiction

Drug therapy -- medications can be used to manage withdrawal symptoms, reduce cravings, or block the effects of the addictive substance. For example, nicotine replacement therapy provides nicotine without the harmful chemicals in cigarettes, while methadone is used as a substitute for heroin. Some medications block the receptor sites that the addictive substance targets, reducing its pleasurable effects.

Strengths: Drug therapy can reduce the immediate physical symptoms of withdrawal, making it easier for the person to stop using the substance. It is relatively easy to administer and can be combined with other treatments.
Limitations: It addresses the physical dependence but may not tackle the psychological causes of the addiction. There is also a risk of becoming dependent on the replacement medication itself. Side effects are possible.

Cognitive behavioural therapy (CBT) -- in the context of addiction, CBT helps the person identify the thought patterns and situations that trigger their substance use. The therapist works with the patient to develop coping strategies, challenge irrational beliefs about the substance (for example, "I need a drink to cope with stress"), and build healthier behavioural responses.

Strengths: CBT addresses the underlying psychological causes of addiction, not just the physical symptoms. It equips the person with long-term coping strategies, reducing the risk of relapse. It has no physical side effects.
Limitations: It requires commitment and motivation, which can be difficult for people in the grip of addiction. Access may be limited by waiting times. It is less effective if used in isolation for severe physical dependence -- it works best alongside other treatments.

Aversion therapy -- this treatment is based on classical conditioning. The addictive substance is repeatedly paired with an unpleasant stimulus (such as a drug that causes nausea when alcohol is consumed). Over time, the person learns to associate the substance with the unpleasant sensation rather than with pleasure, reducing their desire to use it.

Strengths: Aversion therapy can produce rapid results and is based on well-established principles of classical conditioning.
Limitations: The effects may not last long-term once the aversive pairing is no longer reinforced. It raises ethical concerns because it deliberately causes discomfort. It does not address the underlying reasons for the addiction, so relapse rates can be high. Many people drop out of aversion therapy because the experience is unpleasant.

How These Topics Are Assessed on Paper 2

Brain and Neuropsychology and Psychological Problems each have a dedicated section on Paper 2. You should expect questions that test all three assessment objectives.

AO1 (Knowledge and understanding) -- you may be asked to identify parts of the nervous system, describe the function of a brain region, outline the characteristics of depression, or state the features of a theory of addiction. Be precise with terminology.

AO2 (Application) -- you may be given a scenario describing a person's symptoms and asked to explain them using a theory. For example, a scenario about someone with depression might ask you to apply Beck's cognitive triad. Always refer back to the specific details of the scenario and use names and information provided.

AO3 (Evaluation) -- you may be asked to evaluate a brain scanning technique, compare biological and psychological explanations of depression, or discuss the strengths and limitations of a treatment for addiction. Structure your evaluation with clear points, each supported by evidence or reasoning. Use comparative language where appropriate -- for example, "A strength of CBT compared to drug therapy is..."

Extended-response questions (typically 6 or 9 marks) may combine AO1 and AO3, asking you to describe and evaluate a theory or treatment. Plan your answer before you write, allocating roughly equal space to description and evaluation.

Prepare with LearningBro

These two topics carry significant weight on Paper 2 and reward thorough revision. To test your knowledge and identify areas that need more work, try the dedicated courses on LearningBro:

Practise recalling key terms, applying theories to scenarios, and writing timed evaluation paragraphs. The more you retrieve information from memory rather than passively re-reading it, the stronger your neural pathways become -- Hebb would approve.