Welcome to Cognitive Psychology!
Welcome to one of the most exciting parts of your Psychology A Level! Have you ever wondered why you can remember the lyrics to a song from five years ago but forget what you had for breakfast yesterday? Or why two people can see the exact same accident but describe it differently? That is what Cognitive Psychology is all about. It treats the human mind like a powerful computer, looking at how we "input" information, "process" it, and "output" it as memory or behavior. Don't worry if it feels a bit "sci-fi" at first—we will break it down piece by piece!
1. The Multi-Store Model (MSM)
Proposed by Atkinson and Shiffrin (1968), this is the "grandfather" of memory models. It suggests that memory is not one single thing, but a system made of three separate stores.
The Three Stores:
1. Sensory Memory: This is your "waiting room." Information from your senses (eyes, ears, etc.) stays here for a fraction of a second. If you don't pay attention to it, it’s gone!
2. Short-Term Memory (STM): If you pay attention, the info moves here. It has a tiny capacity (about 7 items) and a short duration (about 18–30 seconds).
3. Long-Term Memory (LTM): If you rehearse the information (repeat it over and over), it moves to LTM. This store is potentially infinite and can last a lifetime!
How Information Moves:
Encoding: How information is changed so the brain can store it. (e.g., STM usually encodes acoustically—by sound).
Capacity: How much the store can hold.
Duration: How long the store can hold it.
Retrieval: Taking information out of LTM and bringing it back to STM so you can use it.
Analogy: Think of MSM like a computer. Sensory memory is the mouse click, STM is the RAM (what’s currently on your screen), and LTM is the hard drive where you save your files.
Quick Review: To get information into LTM, you must Attention -> Rehearse -> Store.
Key Takeaway: The MSM shows memory as a linear flow. Its biggest strength is its simplicity, but its weakness is that it might be too simple!
2. The Working Memory Model (WMM)
Baddeley and Hitch (1974) felt the MSM's version of Short-Term Memory was too basic. They argued that STM isn't just a "holding station," but an active "workspace" where we process information.
The Components:
The Central Executive: The "Boss." It drives the system, decides what to pay attention to, and delegates tasks to the "slave systems."
The Phonological Loop: The "Inner Ear." It deals with spoken and written material. (e.g., repeating a phone number in your head).
The Visuo-spatial Sketchpad: The "Inner Eye." It stores visual and spatial information (e.g., picturing how to walk to your next class).
The Episodic Buffer: Added later in 2000, this acts as a "backup" store and bridges memory with LTM and perception.
Did you know? This is why it’s hard to listen to a podcast while writing an essay, but easy to listen to music while washing dishes. Both the podcast and the essay compete for the Phonological Loop!
Key Takeaway: The WMM explains how we can do multi-tasking and why some tasks interfere with each other.
3. Types of Long-Term Memory (Tulving, 1972)
Tulving argued that LTM isn't just one big suitcase. He divided it into two main types of Declarative (fact-based) memory:
1. Episodic Memory: These are memories of personal experiences or "episodes" in your life (e.g., your 10th birthday party). They include details of when and where things happened.
2. Semantic Memory: This is your "mental encyclopedia." It’s your knowledge of facts, meanings, and concepts (e.g., knowing that London is the capital of England). You don't usually remember exactly when you learned these facts.
Memory Aid: Episodic = Events. Semantic = School/Facts.
Key Takeaway: We have different "folders" in our long-term hard drive for personal stories versus general facts.
4. Reconstructive Memory (Bartlett, 1932)
Bartlett famously said that "memory is an imaginative reconstruction." We don't record the world like a video camera; we "re-build" our memories when we recall them.
The Role of Schemas:
Schemas are mental "parcels" of knowledge based on our past experiences. They help us make sense of the world. However, when we remember something, our schemas might "fill in the gaps" with what we expect to happen, rather than what actually happened. This can lead to confabulation (making things up) or rationalization (changing details to fit our culture).
Example: If you see a picture of a messy office, your schema for "offices" might lead you to "remember" seeing a stapler, even if there wasn't one there!
Key Takeaway: Memory is not 100% reliable because our brains try to make things "make sense" using what we already know.
5. Individual and Developmental Differences
Not everyone's "computer software" runs at the same speed! Psychology must consider how memory changes over time and between people.
Processing Speed: Some people naturally process information faster, which can affect how much they can hold in their working memory.
Memory Span (Sebastián and Hernández-Gil, 2012): This study found that our "digit span" (how many numbers we can remember) increases as we age, from about 5 years old until it peaks at age 17.
Alzheimer’s Disease: This condition affects older people by damaging the brain's ability to create new memories and eventually erasing old ones. It often starts by attacking episodic memory first.
Dyslexia: Students with dyslexia often have a shorter phonological loop, making it harder to hold and process spoken sounds or written words in their short-term memory.
6. Classic Study: Baddeley (1966b)
The Goal: To see if LTM encodes information acoustically (by sound) or semantically (by meaning).
The Method: Participants were given four lists of words:
1. Acoustically similar (e.g., cat, mat, hat).
2. Acoustically dissimilar (e.g., pit, few, cow).
3. Semantically similar (e.g., big, large, huge).
4. Semantically dissimilar (e.g., hot, pen, blue).
The Results: When tested for LTM (after a 20-minute delay), participants struggled most with semantically similar words. They got "huge" and "large" mixed up.
The Conclusion: LTM encodes semantically. We get confused by words with similar meanings because that’s how our LTM organizes them!
Common Mistake: Don't confuse this with STM encoding! Baddeley found that Short-Term Memory gets confused by Acoustic similarity, but Long-Term Memory gets confused by Semantic similarity.
7. The Case of Henry Molaison (HM)
HM is the most famous patient in psychology history. To stop his seizures, doctors removed parts of his brain (the hippocampus).
The Result: He could remember his life before the surgery, and his STM worked fine, but he could never form a new long-term memory again. He lived the rest of his life in 30-second loops. This provided huge evidence that STM and LTM are separate stores in the brain!
8. Research Methods in Cognitive Psychology
Cognitive psychologists love Laboratory Experiments because they are scientific and controlled.
Key Terms to Know:
Independent Variable (IV): The thing you change (e.g., the type of word list).
Dependent Variable (DV): The thing you measure (e.g., how many words they remembered).
Hypothesis: A testable prediction. An Alternative Hypothesis predicts an effect, while a Null Hypothesis predicts no effect.
Reliability: If you did the test again, would you get the same result? (Standardized procedures help this).
Validity: Does the test measure real-life memory (Ecological Validity) or just a fake lab task?
Statistical Math (The "Scary" Part made Easy):
Psychologists use tests to see if their results happened by chance.
Probability (p): Usually, we want \(p \leq 0.05\). This means there is only a 5% chance the results are a fluke.
Type I Error: A "False Positive" (The "Boy Who Cried Wolf" – saying there is an effect when there isn't).
Type II Error: A "False Negative" (Missing a real effect).
Mann-Whitney U: Used for independent groups (two different sets of people).
Wilcoxon: Used for repeated measures (the same people doing two tasks).
9. Issues and Debates
Psychology as a Science: Cognitive psychology is very scientific. It uses labs, controls variables, and collects "quantitative" (numerical) data.
Reductionism: This is a criticism. Some say cognitive psychology is "reductionist" because it breaks the complex human mind into simple "boxes and arrows" like a computer, ignoring our emotions and social lives.
Nature vs. Nurture: Our brain structure (Nature) gives us the hardware for memory, but our experiences and schemas (Nurture) fill that hardware with information.
Final Encouragement: Cognitive psychology can be tricky because we can't "see" a memory inside a brain. But by looking at how people behave in experiments, we can build a map of how the mind works. You've got this!