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Unlock This CourseIn 1968, two American psychologists called Richard Atkinson and Richard Shiffrin created one of the most famous models of how our memory works. Think of it like a factory production line - information comes in, gets processed through different stages and either gets stored or thrown away. This model helps us understand why we remember some things but forget others.
The Multistore Model suggests that memory has three separate stores that work together like a team. Today, we're focusing on the very first stage - the Sensory Register - and how attention acts like a bouncer at a club, deciding what gets in and what doesn't.
Key Definitions:
Imagine your brain as a massive security camera system. The sensory register is like having cameras everywhere - recording everything you see, hear, smell, taste and touch. But here's the catch: these recordings only last for a split second before they're deleted forever, unless something important happens.
Every single moment, your senses are bombarded with information. Right now, you're seeing these words, but you're also aware of the temperature, any sounds around you, the feeling of your clothes and much more. The sensory register captures ALL of this information, but it can only hold it for a very short time.
Scientists have identified different types of sensory memory, but two are particularly important for understanding how we process information:
This is your visual sensory memory. It holds images for about 0.5 seconds. Ever noticed how when you close your eyes after looking at something bright, you can still "see" it briefly? That's iconic memory in action!
This is your auditory sensory memory. It lasts longer than iconic memory - about 2-4 seconds. This is why you can sometimes ask "What did you say?" but then answer your own question before the person repeats themselves.
Touch, taste and smell also have sensory registers, but they're less studied. They help us notice immediate changes in our environment, like a sudden temperature change or an unusual smell.
George Sperling wanted to prove that iconic memory exists. He flashed a grid of letters on a screen for just 50 milliseconds (faster than a blink). When people tried to recall all the letters, they could only remember about 4-5. But when he played a tone immediately after the flash to indicate which row to recall, people could remember almost all letters from that row. This proved that all the information was briefly stored in iconic memory, but it faded before people could report it all.
Here's where things get really interesting. Out of all the information flooding into your sensory register every second, only a tiny amount makes it to the next stage. Attention acts like a filter, deciding what's important enough to pay attention to.
Think about being at a busy party. There are dozens of conversations happening, music playing, people moving around, different smells and various visual stimuli. Your sensory register is capturing all of this, but your attention focuses on just one conversation. This is called selective attention.
This is a perfect example of selective attention. Even when you're focused on one conversation, if someone across the room mentions your name, you'll probably notice it. This shows that your brain is still monitoring other information in the background, ready to switch attention when something important comes up.
Not all information has an equal chance of grabbing your attention. Several factors make some things more likely to be noticed than others:
Loud sounds, bright lights, or strong smells are more likely to grab attention. This makes evolutionary sense - sudden loud noises might signal danger!
New or unusual things catch our attention. If you're used to your morning routine, you'll quickly notice if something's different.
Things that matter to you personally are more likely to grab attention. Your name, your interests, or things related to your goals.
Think about how phone notifications work. They're designed to grab attention using many of these principles: they're often loud (intensity), they interrupt what you're doing (novelty) and they're usually personally relevant (messages from friends, updates on things you care about). The notification sound briefly enters your sensory register, but because it meets the criteria for attention, it gets processed further and you check your phone.
The sensory register might seem amazing, but it has some important limitations that affect how we process information:
The biggest limitation is time. Visual information (iconic memory) lasts only about half a second, while auditory information (echoic memory) lasts 2-4 seconds. This might seem like a design flaw, but it's actually quite clever. If we held onto all sensory information for longer, our brains would quickly become overwhelmed.
The brief duration of sensory memory serves an important purpose. It gives us just enough time to decide if something is worth paying attention to, without cluttering our minds with every tiny detail from our environment. It's like having a very efficient spam filter for your brain.
Understanding the sensory register and attention has practical implications for learning and daily life:
When studying, eliminate distractions to help your attention focus on the material. Turn off notifications, find a quiet space and use techniques like highlighting to make important information stand out.
Understanding attention helps explain why hands-free phone calls while driving can still be dangerous. Your auditory attention is divided between the conversation and road sounds.
Advertisers and web designers use principles of attention to make their content more noticeable. Bright colours, movement and personally relevant content all help grab attention.
Psychologists have discovered that people often fail to notice large changes in their visual environment if they're not paying attention to that specific area. In one famous study, participants were asked for directions by a stranger. During the conversation, two people carrying a large door walked between them. While the door blocked their view, the original person asking for directions was replaced by someone completely different. Amazingly, about half the participants didn't notice the switch! This demonstrates how attention acts as a bottleneck - we only process what we're actively attending to.
While the Multistore Model has been hugely influential, it's not perfect. Some psychologists argue that it oversimplifies how memory works. For example, it suggests that attention is like an on/off switch, but research shows that attention can be divided and that we can process some information without conscious awareness.
Despite these limitations, the model remains valuable for understanding the basic principles of how we process information from our environment. It helps explain why we remember some things but not others and why paying attention is so crucial for learning and memory.