Memory: Models and Structures

Memory is usually explained using the Multi-Store Model (Atkinson and Shiffrin). It has three stores: Sensory Register, Short-Term Memory (STM) and Long-Term Memory (LTM). Information moves between stores through attention and rehearsal.

• Sensory Register: holds information for less than half a second; huge capacity but very brief duration.
• STM: limited capacity, around 5 to 9 items (7 plus or minus 2, Miller's magic number); duration is about 18 to 30 seconds without rehearsal.
• LTM: potentially unlimited capacity and duration can last a lifetime.
• Rehearsal (repeating information) moves it from STM to LTM. Without rehearsal, information decays or is displaced from STM.

Capacity, Duration and Coding

Examiners love exact figures here, so learn them precisely.

• STM capacity: 7 plus or minus 2 items (Miller).
• STM duration: roughly 18-30 seconds unless rehearsed.
• LTM duration: can be unlimited, up to a lifetime.
• Coding is how information is stored: STM mainly codes acoustically (by sound), LTM mainly codes semantically (by meaning).

Forgetting

Two key explanations of forgetting:

• Trace decay: memory trace fades naturally over time if not used.
• Interference: forgetting happens because other memories get in the way. Proactive interference is old memories disrupting new ones; retroactive interference is new memories disrupting old ones.
• Retrieval failure: information is available but not accessible without the right cue (context or state-dependent cues).

Strategies to Improve Memory

These come up often in application questions:

• Chunking: grouping information into meaningful units to beat the 7 plus or minus 2 limit.
• Organisation: using categories or hierarchies to structure information for easier recall.
• Elaborative rehearsal: linking new information to existing knowledge, deeper than simple repetition.
• Dual coding: combining verbal and visual information (words and pictures together) to strengthen memory.
• Mnemonics: acronyms, imagery and the method of loci to aid recall.

Common Mistakes to Avoid

• Do not mix up STM capacity (7 plus or minus 2 items) with STM duration (18-30 seconds); they are different figures for different things.
• Do not say LTM capacity is 'infinite' without qualifying it as 'potentially unlimited'.
• Remember interference and retrieval failure are different theories: interference is about competing memories, retrieval failure is about missing cues.
• Always link strategies (like chunking or dual coding) back to a named study or theory when answering evaluate questions.
• Use correct terminology: 'encoding', 'storage' and 'retrieval' are the three key memory processes examiners expect you to reference.

Perception - the basics

Perception is how the brain organises and interprets sensory information (mostly visual) to make sense of the world. It is different from sensation, which is just raw data hitting the eyes.

• Visual information travels from the retina, along the optic nerve, to the visual cortex, where it is processed.
• The brain uses depth cues, size cues and past experience to build a 3D understanding from a 2D image on the retina.

Monocular and binocular depth cues

Depth cues let us judge distance and 3D space.

• Monocular cues need only one eye: height in plane, relative size, occlusion (overlap) and linear perspective.
• Binocular cues need two eyes: retinal disparity (each eye sees a slightly different image) and convergence (eye muscles turn inward for close objects).

Visual illusions

Illusions show that perception can be tricked, which proves perception is a constructed process, not a direct copy of reality.

• Ambiguous figures: an image with two possible interpretations, like the Necker cube or the rabbit-duck.
• Fiction: the brain creates something that is not really there, like the Kanizsa triangle.
• Size constancy failures, such as the Ponzo illusion, where linear perspective tricks the brain into misjudging size.

Explaining perception: two theories

• Gregory's constructivist theory: perception is an active process built from past experience and expectation (top-down processing). This explains why illusions happen, because the brain makes a 'best guess'.
• Gibson's direct theory: perception comes straight from the environment itself, using optic flow and affordances, with no need for past experience (bottom-up processing).

Factors affecting perception

• Culture: research (such as Hudson's studies) suggests people from non-Western cultures with less exposure to 2D pictures show less susceptibility to some illusions.
• Emotion: perception can be affected by mood, for example anxiety making a situation seem more threatening.
• Motivation: hunger or need can change what a person notices or how they interpret ambiguous stimuli.
• Expectation: if you expect to see something, you are more likely to perceive it that way (linked to top-down processing).

Common mistakes

• Do not confuse monocular and binocular cues - always double check which needs one eye and which needs two.
• Do not muddle Gregory (top-down, past experience) with Gibson (bottom-up, direct from environment) - examiners love testing this swap.
• Remember illusions are evidence FOR constructivist theory, not against it.
• 'Perception' and 'sensation' are not the same thing - sensation is the raw input, perception is the interpretation.

Brain development basics

The brain is not fully developed at birth. It keeps changing across childhood and adolescence through two key processes: synaptic pruning and myelination.

• Synaptic pruning: unused connections (synapses) between neurons are removed to make the brain more efficient. 'Use it or lose it.'
• Myelination: nerve fibres get coated in a fatty myelin sheath, which speeds up signals travelling along the neuron. This continues into a person's twenties, especially in the frontal lobe.

The frontal lobe and adolescence

The frontal lobe controls decision-making, impulse control, planning and risk assessment. It is one of the LAST areas to fully develop, often not maturing until the mid-twenties. This is used to explain why teenagers can be more impulsive and take more risks than adults, even when they know the danger. Common mistake: don't say teenagers 'can't think properly' — the frontal lobe works, it is just still developing, so self-control and long-term planning are weaker than in adults.

Blakemore and Choudhury (2006)

This is the key study for this topic. Blakemore and Choudhury reviewed brain-scanning research and concluded that the prefrontal cortex undergoes significant structural change during adolescence, which links to risk-taking behaviour and social/emotional development in teenagers. Learn: it's a review study (not a single experiment), it uses brain-imaging evidence, and it links brain development directly to behaviour change.

Practical applications

This research is applied to real life:

• Explaining why the age of criminal responsibility and driving laws are set where they are.
• Supporting arguments about how teenagers should be treated differently to adults in the justice system, since their brains are still maturing.
• Informing school and parenting approaches to risk-taking behaviour.

Nature vs nurture link

Brain development shows an interaction: the brain matures biologically (nature) but experience and environment shape which synapses are kept through pruning (nurture). Common mistake: students often write this topic as pure biology — always mention that environment influences which connections survive pruning.

Command word tips

• 'Describe' Blakemore and Choudhury = explain what the study found (structural changes in prefrontal cortex during adolescence).
• 'Evaluate' = strengths (uses objective brain-scan data) vs weaknesses (correlational, can't prove the brain changes CAUSE the behaviour, based on a review not one controlled experiment).
• Always link brain structure back to a real behaviour (risk-taking, impulsivity, decision-making) for full marks.

What is social influence?

Social influence is the process by which other people's words, actions or presence change our thoughts, feelings or behaviour. OCR's specification splits it into conformity, obedience and other people (bystander behaviour, deindividuation and prosocial/antisocial effects of others).

Conformity

Conformity is changing behaviour or opinions to fit in with a group, even without direct pressure.

• Compliance: going along publicly but not privately agreeing - the weakest and least lasting type.
• Identification: adopting behaviour because you value belonging to a group (eg a new job or team).
• Internalisation: genuinely accepting the group's beliefs as your own, publicly and privately - the deepest and most permanent type.
• Asch's line-judgement research is the classic conformity study: naive participants agreed with an obviously wrong majority on a large proportion of trials, showing normative social influence (wanting approval) and informational social influence (wanting to be right when unsure).

Obedience

Obedience means following a direct order from someone seen as an authority figure.

• Milgram's obedience research found many participants delivered what they believed were dangerous electric shocks when instructed by an authority figure in a lab coat, even against their own judgement.
• Situational factors affecting obedience: proximity to the victim, proximity/legitimacy of the authority figure, location (prestigious setting increases obedience), and having others who resist (an ally reduces obedience).
• Common mistake: students confuse obedience (a direct order from someone with power) with conformity (matching a group with no direct order) - always state which one a scenario shows and why.

Other people: bystanders and deindividuation

• Bystander effect: the more people present at an emergency, the less likely any one person is to help, due to diffusion of responsibility (each person feels less personally responsible).
• Pluralistic ignorance: bystanders look to others' reactions and, if nobody reacts, assume it isn't an emergency.
• Deindividuation: losing your sense of personal identity in a crowd or when anonymous (eg hood up, uniform, online anonymity), which can increase antisocial behaviour because people feel less accountable.
• Prosocial behaviour is helping others with no obvious reward; antisocial behaviour harms others or society - groups and crowds can produce either depending on context and norms.

Exam tips

• Always link a named study or theory (Asch, Milgram, bystander effect) to the specific scenario in the question.
• Use key terms accurately: normative vs informational influence, and compliance vs identification vs internalisation, are easy marks if defined precisely.
• Evaluate using real-world application, eg using knowledge of obedience to design safer hospital or workplace procedures.

Defining psychological problems

Psychologists use several ways to decide if behaviour counts as a 'psychological problem'. No single definition works alone, so exam answers should use more than one.

• Deviation from social norms: behaviour that breaks the unwritten rules of society (e.g. talking to yourself loudly in public).
• Failure to function adequately: the person can't cope with daily life (Rosenhan and Seligman's 7 features include distress, maladaptiveness, unpredictability, irrationality).
• Deviation from ideal mental health: Jahoda's list of qualities a 'healthy' person should have (e.g. accurate perception of reality, self-esteem, autonomy) — anyone missing these is judged abnormal.
• Statistical infrequency: behaviour that is rare/unusual compared to the rest of the population (statistically in the minority, e.g. bottom or top 2 percent).

Common mistakes

Students often give only ONE definition when the question asks to 'discuss' — always compare at least two. Also remember each definition has weaknesses: deviation from social norms changes over time and between cultures; statistical infrequency wrongly labels rare positive traits (like very high IQ) as abnormal.

Explanations of psychological problems

OCR requires you to know biological and psychological (learning theory) explanations.

• Biological approach: problems are caused by genetics (inherited via family/twin studies), neurotransmitter imbalance (e.g. low serotonin linked to depression), or brain structure differences.
• Behaviourist (learning) approach: problems are learned through classical conditioning (association, e.g. a phobia learned by pairing a stimulus with fear) and operant conditioning (reinforcement, e.g. avoidance behaviour rewarded by anxiety reduction).

Treatments

Each explanation links to a treatment type — always match them up in exam answers.

• Biological treatments: drug therapy (e.g. antidepressants adjusting neurotransmitter levels).
• Behaviourist treatments: systematic desensitisation for phobias (gradual exposure paired with relaxation, building an anxiety hierarchy) and flooding (immediate full exposure).

Key study

Know at least one classic study, such as Rosenhan's 'sane in insane places' study on diagnosis, to use as evaluation evidence.

Exam tip

Questions often ask you to apply definitions/explanations to a scenario — always name the correct term (e.g. 'this is deviation from social norms because...') rather than just describing behaviour.

Why research methods matter

OCR GCSE Psychology tests you on how psychologists study behaviour scientifically. You need to know each method, when to use it, and its strengths and weaknesses. Examiners love asking you to identify a method from a scenario, so learn the exact definitions.

Experiments

An experiment tests a hypothesis by manipulating an independent variable (IV) and measuring a dependent variable (DV), while controlling extraneous variables.

• Laboratory experiment: controlled setting, high control, but can lack ecological validity.
• Field experiment: real-life setting, IV still manipulated, more natural behaviour but less control.
• Natural experiment: the IV occurs naturally (researcher does not manipulate it), useful when it would be unethical or impossible to change the IV, but cause and effect is harder to prove.

Types of experimental design

• Independent groups: different participants in each condition. No order effects, but participant variables can bias results.
• Repeated measures: same participants do both conditions. Controls participant variables, but order effects (practice or fatigue) can occur, fixed by counterbalancing.
• Matched pairs: different participants but matched on key variables like age or IQ. Reduces participant variables without order effects, but time-consuming and matching is never perfect.

Non-experimental methods

• Questionnaires: written questions, can be open (qualitative, detailed) or closed (quantitative, easy to analyse). Watch for social desirability bias.
• Interviews: structured (fixed questions, easy to compare), unstructured (flexible, richer detail), or semi-structured (a mix).
• Observations: naturalistic (real setting, no control) versus controlled (lab setting, more control). Can be participant (researcher joins in) or non-participant, and overt (participants know) or covert (they do not).
• Correlations: measure the relationship between two co-variables using a correlation coefficient from -1 to +1. Correlation does NOT mean causation, a very common exam trap.
• Case studies: in-depth study of one person or small group, rich detail but not generalisable.

Sampling methods

• Random sampling: every member of the population has an equal chance of selection, e.g. names out of a hat.
• Opportunity sampling: whoever is available at the time, quick but biased.
• Volunteer (self-selected) sampling: participants respond to an advert, easy but attracts a particular type of person.
• Systematic sampling: selecting every nth person from a list.

Ethics (BPS guidelines)

You must know: informed consent, right to withdraw, confidentiality, protection from harm, and debriefing. Deception is only allowed if fully justified and followed by a full debrief.

Data and evaluation

Quantitative data is numerical and easy to analyse statistically. Qualitative data is descriptive, richer but harder to compare. Reliability means consistency of results; validity means the study measures what it claims to measure. A common mistake is confusing these two terms, so learn them precisely.