Memory: Cognitive Explanations

What you'll learn

This revision guide covers cognitive explanations of memory as specified in the OCR GCSE Psychology syllabus. You'll explore how psychologists explain memory processes through models and theories, focusing on the multi-store model, encoding processes, and explanations for forgetting. This content is essential for Paper 1 and frequently appears in both short-answer and extended-response questions.

Key terms and definitions

Encoding — the process of converting information into a form that can be stored in memory (visual, acoustic, or semantic)

Storage — retaining encoded information in memory over time

Retrieval — recovering stored information from memory when needed

Short-term memory (STM) — temporary memory store with limited capacity (5-9 items) and duration (18-30 seconds without rehearsal)

Long-term memory (LTM) — permanent memory store with unlimited capacity and potentially lifetime duration

Rehearsal — repeating information to keep it in STM or transfer it to LTM

Interference — forgetting that occurs when one memory disrupts the recall of another memory

Retrieval failure — inability to access stored memories due to absent or inadequate retrieval cues

Core concepts

The multi-store model of memory

The multi-store model (Atkinson and Shiffrin, 1968) proposes that memory consists of three separate stores that differ in capacity, duration, and encoding.

Sensory register:

• Holds incoming sensory information very briefly (milliseconds)
• Has separate stores for each sense (iconic for visual, echoic for auditory)
• Information decays rapidly unless attention is paid to it
• Very large capacity but extremely short duration

Short-term memory (STM):

• Receives information from sensory register through attention
• Limited capacity: Miller (1956) suggested 7±2 items
• Limited duration: 18-30 seconds without rehearsal (Peterson and Peterson, 1959)
• Primarily acoustic encoding (Baddeley, 1966)
• Information is lost through decay or displacement

Long-term memory (LTM):

• Receives information from STM through rehearsal
• Unlimited capacity and potentially permanent duration
• Primarily semantic encoding (Baddeley, 1966)
• Information retrieved back to STM for use

Transfer between stores:

• Attention transfers information from sensory register to STM
• Maintenance rehearsal keeps information in STM
• Elaborative rehearsal transfers information from STM to LTM
• Retrieval brings information from LTM back to STM

Encoding in memory

Types of encoding:

Different memory stores encode information in different ways:

Acoustic encoding — storing information as sounds. STM primarily uses acoustic encoding. When you try to remember a phone number by repeating it to yourself, you're using acoustic encoding.

Visual encoding — storing information as images or pictures. The sensory register uses visual encoding for what we see (iconic memory).

Semantic encoding — storing information according to its meaning. LTM primarily uses semantic encoding, which is why understanding material helps you remember it better for exams.

Evidence for encoding differences:

Baddeley (1966) demonstrated that STM and LTM use different encoding systems:

• Participants struggled to recall acoustically similar words (cat, mat, sat) from STM immediately after presentation
• They had more difficulty recalling semantically similar words (large, huge, big) from LTM after 20 minutes
• This shows STM uses acoustic encoding (sound confusion) while LTM uses semantic encoding (meaning confusion)

Capacity and duration

Capacity of STM:

Miller (1956) researched STM capacity and concluded people can hold approximately 7±2 items (between 5 and 9 items). This can be increased through chunking — grouping individual items into meaningful units. For example, remembering the sequence "FBI-BBC-NHS" is easier than "FBIBBCNHS" because it's chunked into three familiar acronyms rather than nine letters.

Duration of STM:

Peterson and Peterson (1959) demonstrated STM duration:

• Participants heard trigrams (three consonants like XQJ)
• They counted backwards in threes to prevent rehearsal
• After 3 seconds, recall was about 80%
• After 18 seconds, recall dropped to approximately 10%
• This shows STM duration is around 18-30 seconds without rehearsal

Duration of LTM:

Bahrick et al. (1975) studied LTM duration by testing participants' memory for school classmates:

• Photo recognition remained around 90% accurate after 15 years
• Free recall of names was approximately 60% after 15 years
• Even after 48 years, photo recognition was about 70% accurate
• This demonstrates LTM can last decades or even a lifetime

Explanations for forgetting

Interference theory:

Interference occurs when one memory disrupts another, causing forgetting. There are two types:

Proactive interference — old memories disrupt new memories. For example, calling your new teacher by your previous teacher's name because the old memory interferes with forming the new one.

Retroactive interference — new memories disrupt old memories. For example, learning a new mobile number makes it harder to recall your old number because the new information interferes with the old.

Research evidence from McGeoch and McDonald (1931):

• Participants learned a list of words then learned a second list
• Those who learned similar words in the second list recalled fewer words from the first list
• Those who learned numbers or rested recalled more from the first list
• This demonstrates retroactive interference is strongest when memories are similar

Retrieval failure:

Forgetting occurs when we lack appropriate cues to access stored memories. The encoding specificity principle (Tulving and Thomson, 1973) states that memory is best when retrieval conditions match encoding conditions.

Context-dependent forgetting — environmental context at encoding and retrieval differ. Godden and Baddeley (1975) demonstrated this:

• Divers learned word lists either underwater or on land
• Recall was approximately 40% better when learning and recall environments matched
• Those who learned underwater recalled best underwater; those who learned on land recalled best on land

State-dependent forgetting — internal state at encoding and retrieval differ. This includes emotional state or level of arousal. Students sometimes perform better in exams when they're in a similar emotional state to when they revised.

Strengths and limitations of the multi-store model

Strengths:

• Supported by research showing STM and LTM are different (Baddeley's encoding studies)
• Brain damage case studies support separate stores (HM could form STM but not LTM after surgery)
• Explains primacy and recency effects in free recall tasks
• Uses scientific laboratory experiments providing controlled evidence

Limitations:

• Oversimplified: LTM isn't one single store (episodic, semantic, and procedural memories are different)
• Rehearsal isn't always necessary for LTM transfer (you remember shocking events without rehearsal)
• STM is more complex than suggested (working memory model better explains this)
• Research often uses artificial tasks (word lists) that don't reflect everyday memory use

Worked examples

Example 1: Describe and evaluate question (6 marks)

Question: Describe and evaluate the multi-store model of memory. [6 marks]

Model answer:

The multi-store model (Atkinson and Shiffrin, 1968) proposes memory consists of three separate stores. Information flows from the sensory register through attention to short-term memory, which has limited capacity (7±2 items) and duration (18-30 seconds). Through rehearsal, information transfers to long-term memory, which has unlimited capacity and potentially permanent duration. [3 marks for description]

One strength is research evidence from Baddeley (1966) showing STM uses acoustic encoding while LTM uses semantic encoding, supporting the idea of separate stores. However, a limitation is that the model oversimplifies LTM, which actually consists of different types (episodic, semantic, procedural) rather than one single store. Additionally, rehearsal isn't always necessary for LTM formation, as we remember distinctive events without rehearsing them. [3 marks for evaluation]

Mark scheme guidance:

• Award up to 3 marks for accurate description of the model
• Award up to 3 marks for evaluation (strengths and/or limitations with evidence)
• Look for named psychologists and dates where appropriate

Example 2: Application question (4 marks)

Question: Jake is revising for his exams. He reads through his notes once, then tests himself by writing down everything he can remember. Explain how encoding specificity might affect Jake's exam performance. [4 marks]

Model answer:

Encoding specificity states that memory is best when conditions at retrieval match conditions at encoding. If Jake revises in his bedroom but takes the exam in a school hall, the different environmental contexts mean retrieval cues present during encoding (bedroom furniture, posters, familiar surroundings) are absent during retrieval (exam hall). This context-dependent forgetting could reduce his recall compared to if both environments matched. Research by Godden and Baddeley with divers supports this, showing recall was approximately 40% better when learning and recall environments matched. [4 marks]

Mark scheme guidance:

• 1 mark for identifying encoding specificity/context-dependent memory
• 1 mark for explaining the mismatch between encoding and retrieval
• 1 mark for applying this to Jake's specific situation
• 1 mark for research evidence or elaboration

Example 3: Research methods question (3 marks)

Question: Peterson and Peterson (1959) investigated the duration of short-term memory. Identify one ethical issue that might arise in this study and explain how researchers could address it. [3 marks]

Model answer:

One ethical issue is informed consent. Participants might not understand what the study involves or that they'll be asked to count backwards while trying to remember meaningless letter combinations. Researchers could address this by providing a detailed information sheet explaining the procedure before participants agree to take part, ensuring they understand they'll complete memory tasks with distraction techniques and can withdraw at any time. [3 marks]

Mark scheme guidance:

• 1 mark for identifying a relevant ethical issue
• 2 marks for explaining how to address it with specific detail

Common mistakes and how to avoid them

• Confusing capacity and duration: Capacity refers to how much information can be stored (STM: 7±2 items; LTM: unlimited). Duration refers to how long information lasts (STM: 18-30 seconds; LTM: potentially lifetime). Use these terms precisely.

• Mixing up interference types: Proactive = old interferes with new (think "pro" = before, like "prologue"). Retroactive = new interferes with old (think "retro" = backwards). Create a memory technique to distinguish them.

• Forgetting to name psychologists and dates: In describe and evaluate questions, including researchers' names and years strengthens your answer. "Baddeley (1966)" is more creditworthy than "a study showed."

• Describing when asked to evaluate: "Describe" means outline what something is. "Evaluate" means assess strengths and limitations with evidence. Read command words carefully.

• Not applying knowledge to scenarios: Application questions require you to use psychological concepts to explain a specific situation. Always refer back to the scenario details (like "Jake" or "the divers") rather than writing generally about the concept.

• Writing about the working memory model instead of multi-store model: These are different models. The multi-store model (Atkinson and Shiffrin) has three stores; working memory model (Baddeley and Hitch) explains STM structure. Know which the question asks for.

Exam technique for "Memory: Cognitive Explanations"

• Command words matter: "Describe" requires factual detail about what/how. "Explain" needs reasons why something happens. "Evaluate" demands judgement with strengths and limitations. "Discuss" combines description and evaluation. Identify the command word before you start writing.

• Use the mark allocation: If a question is worth 4 marks, aim for four distinct points or two well-developed points. Don't write three paragraphs for 2 marks or one sentence for 6 marks. Approximately one mark equals one developed point.

• Include psychological evidence: Research studies, psychologists' names, and dates demonstrate knowledge. For example, citing "Peterson and Peterson (1959)" when discussing STM duration shows specific understanding rather than vague knowledge.

• Structure extended responses: For 6-mark questions, use a clear structure: introduction defining key terms, main body with description/explanation, evaluation paragraph with evidence. This logical organisation helps examiners award marks efficiently.

Quick revision summary

Memory cognitive explanations focus on mental processes in remembering and forgetting. The multi-store model proposes three separate stores (sensory register, STM, LTM) differing in capacity, duration, and encoding. STM holds 7±2 items for 18-30 seconds using acoustic encoding. LTM has unlimited capacity and duration using semantic encoding. Forgetting occurs through interference (proactive and retroactive) or retrieval failure (context and state-dependent). Research evidence from Baddeley, Peterson and Peterson, and Godden and Baddeley supports these explanations.