Welcome to the World of Memory!
Ever wondered why you can remember the lyrics to a song from five years ago but forget what you had for breakfast yesterday? Memory is one of the most fascinating parts of Psychology. In this chapter, we aren't just looking at memory as a "storage box"; we are looking at how our brains encode (process), store, and retrieve information. Don't worry if it seems like a lot to take in—we'll break it down step-by-step!
1. The Multi-Store Model (MSM)
Proposed by Atkinson and Shiffrin, this model suggests that memory is made up of three separate stores. Think of it like a computer system: information comes in, gets processed, and is either saved to the hard drive or deleted.
The Three Stores
1. Sensory Register: This is where information from your senses (sight, sound, etc.) first arrives. It has a huge capacity but a very short duration (less than half 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 is a "fragile" store. Its capacity is limited to about \(7 \pm 2\) items. Its duration is about 18–30 seconds.
3. Long-Term Memory (LTM): If you rehearse the information (repeat it over and over), it moves here. This store is potentially unlimited in both capacity and duration.
Key Features to Remember
For each store, you need to know three things: Coding (how it's stored), Capacity (how much), and Duration (how long).
Memory Aid: Think of the 3 Cs and a D—Coding, Capacity, Connection (how info moves), and Duration.
Quick Review:
- STM Coding: Mainly Acoustic (sounds).
- LTM Coding: Mainly Semantic (meaning).
- STM Capacity: \(7 \pm 2\) items (Miller’s Magic Number).
- LTM Capacity: Unlimited.
Key Takeaway: Information flows from the environment into the Sensory Register, then to STM through attention, and finally to LTM through rehearsal.
2. Types of Long-Term Memory (LTM)
Not all long-term memories are the same! Psychologists like Tulving realized that "knowing how" to ride a bike is different from "knowing that" Paris is the capital of France.
The Three Types:
1. Episodic Memory: These are memories of events in your life. Like a diary entry.
Example: Your 10th birthday party or what you did last weekend.
2. Semantic Memory: This is your "mental encyclopedia." It’s your knowledge of the world and facts.
Example: Knowing that 2 + 2 = 4 or what a "dog" is.
3. Procedural Memory: These are memories of actions or skills. You usually do these without thinking.
Example: Riding a bike, tying your shoelaces, or typing on a keyboard.
Did you know? Procedural memories are often "muscle memories." This is why even people with severe amnesia can sometimes still play the piano perfectly, even if they can't remember what they had for lunch!
Key Takeaway: LTM is divided into knowing "when/where" (Episodic), knowing "what" (Semantic), and knowing "how" (Procedural).
3. The Working Memory Model (WMM)
Baddeley and Hitch thought the Multi-Store Model was too simple. They argued that STM isn't just one "box," but an active "workspace" that handles different types of information at the same time.
The Components:
1. Central Executive: The "boss." It monitors incoming data and allocates tasks to the other components. It has very limited storage.
2. Phonological Loop: Deals with auditory information (sounds). It has two parts: the Phonological Store (inner ear) and the Articulatory Process (inner voice used for rehearsal).
3. Visuo-Spatial Sketchpad: Deals with visual and spatial information. Think of it as your "inner eye." If you visualize how many windows are in your house, you are using this.
4. Episodic Buffer: Added later in 2000. It's a temporary store that integrates information from the other components and links it to Long-Term Memory.
Analogy: Imagine a chef (Central Executive) in a kitchen. He has a helper for chopping veg (Phonological Loop) and another for plating up (Visuo-Spatial Sketchpad). The Episodic Buffer is like the tray that brings the whole meal together.
Key Takeaway: Working memory is active and multi-tasking. It can do two different tasks (one visual, one verbal) easily, but struggles with two tasks of the same type.
4. Why Do We Forget?
Forgetting isn't just "losing" a file; it's often because of a mix-up or a lack of clues.
1. Interference
This happens when one memory gets in the way of another. It’s most likely to happen when the memories are similar.
- Proactive Interference: Old memories disrupt new ones.
Example: You get a new phone number but keep giving people your old one.
- Retroactive Interference: New memories disrupt old ones.
Example: You learn a new dance routine, and now you can't remember the one you learned last month.
2. Retrieval Failure (Cues)
The memory is there, but you can’t find it because you don't have the right "trigger" or cue. This is the "tip of the tongue" feeling.
- Context-Dependent Forgetting: Forgetting because the environment is different (e.g., you go to the kitchen to get something, forget what it was, but remember when you go back to the living room).
- State-Dependent Forgetting: Forgetting because your internal mood/state is different (e.g., learning something while happy and forgetting it when you are sad).
Key Takeaway: We forget because of interference (clashing memories) or retrieval failure (missing cues).
5. Eyewitness Testimony (EWT)
In court, witnesses are asked to recall what they saw. But memory is reconstructive—it's not a perfect video recording!
Factors Affecting Accuracy:
1. Misleading Information:
- Leading Questions: Questions that suggest a certain answer. (Loftus and Palmer’s study found that saying a car "smashed" led to higher speed estimates than saying it "hit").
- Post-Event Discussion: When witnesses talk to each other, their memories can become contaminated with "bits" from other people’s stories.
2. Anxiety:
- High anxiety can make memory worse because we focus on the threat (e.g., "Weapon Focus"—looking at the gun instead of the attacker’s face).
- However, some anxiety can actually improve memory by making us more alert. It follows an "Inverted-U" shape performance curve.
Common Mistake: Don't assume anxiety always makes memory worse! It’s a bell curve—a little bit of stress helps, but too much is bad.
Key Takeaway: Our memories of events can be altered by the words people use when questioning us or by talking to other witnesses.
6. Improving Accuracy: The Cognitive Interview
To help police get better information, Fisher and Geiselman developed the Cognitive Interview based on psychological principles.
The Four Techniques:
1. Report Everything: Mention every tiny detail, even if it seems irrelevant. It might trigger other important memories.
2. Reinstate the Context: Imagine you are back at the scene. What was the weather like? How did you feel? (This provides retrieval cues).
3. Reverse the Order: Describe the event from the end to the beginning. This prevents people from using their "expectations" of what usually happens.
4. Change Perspective: Imagine the scene from the view of another witness or a person standing across the street. This helps disrupt the effect of schemas (pre-set ideas).
Encouragement: You’ve made it to the end of the chapter! Memory is a core part of your exam, and mastering these models and theories will give you a great foundation for the rest of Psychology. Keep reviewing these "Key Takeaways," and you'll do great!