Structures of Memory » Murdock Serial Position Curve Study

What you'll learn this session

Study time: 30 minutes

Understand what the serial position curve is and why it's important
Learn about Murdock's classic 1962 study on serial position effect
Explore the primacy and recency effects in memory
Examine the methodology and findings of Murdock's experiment
Understand how this research relates to different memory stores
Apply this knowledge to improve your own memory techniques

The Serial Position Effect in Memory

Have you ever noticed that when you're trying to remember a list of items, you tend to recall the first few and last few items better than those in the middle? This common memory phenomenon is called the serial position effect and it's one of the most reliable findings in memory research.

Key Definitions:

Serial Position Effect: The tendency to remember items at the beginning and end of a list better than those in the middle.
Primacy Effect: Better recall of items at the beginning of a list.
Recency Effect: Better recall of items at the end of a list.

💡 Primacy Effect

When we see or hear a list, the first few items get more rehearsal time in our short-term memory, increasing the chance they'll transfer to long-term memory. This is why we remember these items better - they've been processed more deeply.

🚀 Recency Effect

The last few items on a list are still in our short-term memory when we're asked to recall them. They haven't had time to fade away, so we can easily retrieve them - but only for a short while after learning.

Murdock's Serial Position Curve Study (1962)

In 1962, psychologist Bennet B. Murdock conducted one of the most famous studies demonstrating the serial position effect. His research has become a cornerstone in our understanding of how memory works.

The Experiment Setup

Murdock wanted to test how well people could remember words depending on where they appeared in a list. Here's how he did it:

👥 Participants

Murdock tested undergraduate students from the University of Toronto.

📝 Materials

Lists of common English words (like 'cat', 'tree', 'book') varying in length from 10 to 40 words.

⏱ Procedure

Words were presented one at a time, at a rate of one word every 2 seconds.

Study Details: The Method

In his most cited experiment, Murdock used 20-word lists. After each list was presented, participants were asked to write down as many words as they could remember in any order (free recall). This was repeated with multiple lists to get reliable data.

The key innovation was that Murdock tracked not just how many words people remembered, but also which positions in the list those words came from.

What Murdock Found: The Serial Position Curve

When Murdock plotted his results on a graph, he found a distinctive U-shaped curve that has since become famous in psychology:

📊 The Results

Murdock found that recall was highest for words at the beginning of the list (positions 1-3) and at the end of the list (the last 6-8 words). Words in the middle were recalled much less frequently. This U-shaped pattern is what we call the serial position curve.

🤔 The Interpretation

This pattern supported the multi-store model of memory proposed by Atkinson and Shiffrin. The primacy effect (remembering early items) suggested transfer to long-term memory, while the recency effect (remembering late items) showed the operation of short-term memory.

Testing the Recency Effect

Murdock and other researchers conducted follow-up experiments to further understand these effects. One key finding came from adding a simple distractor task:

The Distractor Task Experiment

When participants were asked to count backwards for 30 seconds immediately after seeing the list (before recall), the recency effect disappeared almost completely. The primacy effect remained intact.

This suggested that the recency effect relies on short-term memory, which is disrupted by new information. The primacy effect, however, relies on long-term memory which is more resistant to such disruption.

Why Murdock's Study Matters

Murdock's research was groundbreaking for several reasons:

It provided strong evidence for the multi-store model of memory
It demonstrated that memory isn't a simple recording process - it varies based on timing and position
It helped explain everyday memory experiences we all have
It established a methodology that researchers still use today

The Serial Position Effect in Real Life

Understanding the serial position effect has practical applications in many areas:

🎓 Education

Teachers might present the most important information at the beginning or end of a lesson to improve retention.

💻 Advertising

Advertisers often put key messages at the start and end of commercials, knowing these positions are better remembered.

📚 Studying

When revising, taking regular breaks can help overcome the serial position effect by creating multiple "first" and "last" sections.

Strengths and Limitations of Murdock's Study

✅ Strengths

High control of variables in a laboratory setting
Clear, measurable results that have been replicated many times
Used simple materials (common words) that minimised confounding variables
Findings have practical applications in everyday life

❌ Limitations

Laboratory setting lacks ecological validity - we don't usually memorise random word lists in real life
Sample was limited to university students, who may have better memory strategies than the general population
Only tested free recall - other memory tasks might show different patterns
Doesn't account for individual differences in memory ability

How to Use This Knowledge in Your Exams

Understanding Murdock's study is valuable for your GCSE Psychology exams. Here's what to remember:

Exam Tips for Discussing Murdock's Study

Be specific: Mention the year (1962) and key details of the methodology
Explain both effects: Make sure you can clearly explain both primacy and recency effects
Link to theory: Connect the findings to the multi-store model of memory
Evaluate: Discuss both strengths and limitations of the study
Apply: Give examples of how the serial position effect applies to real-life situations

Improving Your Own Memory

You can use knowledge of the serial position effect to improve your own memory and study techniques:

Chunking information: Break long lists into smaller groups to create multiple primacy and recency effects
Spaced repetition: Review information at intervals to strengthen memory
Pay extra attention: Make a conscious effort to focus on information in the middle of lists or study sessions
Create associations: Link items in the middle to something memorable to overcome the serial position effect

Summary: Key Points About Murdock's Study

Murdock's 1962 study on the serial position effect demonstrated that:

👉 The Findings

Items at the beginning of a list (primacy effect) and end of a list (recency effect) are remembered better than those in the middle, creating a U-shaped recall curve.

🎯 The Significance

This pattern supports the multi-store model of memory, suggesting that primacy effects relate to long-term memory while recency effects relate to short-term memory.

Understanding this study helps explain how our memory works and provides practical strategies for improving memory in everyday life and academic settings.

🧠 Test Your Knowledge!