Memory facts for kids

Overview of the forms and functions of memory in the sciences

Memory is your brain's amazing ability to store and recall information from your past experiences. It's like your personal record of everything you've seen, heard, felt, and learned! Scientists who study how our brains work, especially how we think and remember, call this field "cognitive psychology".

There are three main types of memory that help us remember different things for different lengths of time:

• Short-term memory: This is for holding information for a very brief period, like remembering a phone number just long enough to dial it.
• Sensory memory: This is the super-quick memory that captures what your senses (sight, sound, touch) notice for a split second, like the smell of a flower or a quick flash of light.
• Long-term memory: This is where you store information for a long time, sometimes even your whole life, like remembering a fun holiday you had last year or how to ride a bike.

Sometimes, people experience memory loss, which is often called forgetfulness or amnesia.

What is Sensory Memory?

Sensory memory is the very first, super-fast stage of memory. It holds sensory information (what you see, hear, or feel) for less than a second after you experience it. Think of it like a quick snapshot or a tiny recording of your senses. You don't even have to try to remember; it happens automatically!

For example, if you quickly glance at a picture, your sensory memory holds that image for a tiny moment, even if you can't describe every detail. A scientist named George Sperling did famous experiments in 1963 to show how this works. He found that our sensory memory can hold about 12 items, but they disappear very, very quickly – within a few hundred milliseconds (that's less than half a second!). Because it fades so fast, you can't really practice to keep sensory memories longer.

There are three main kinds of sensory memory:

• Iconic memory: This is for visual information, like a quick flash of an image.
• Echoic memory: This is for sounds, like briefly remembering the last few words someone said.
• Haptic memory: This is for touch sensations.

What is Short-Term Memory?

Short-term memory is also known as working memory because it's where your brain actively holds and works with information for a short time. It allows you to remember things for a few seconds up to about a minute without repeating them over and over.

However, its capacity is quite limited. A famous researcher named George Armitage Miller (1956) found that most people can only hold about 7 items (plus or minus 2) in their short-term memory at once. More recent studies suggest it might be even less, around 4 or 5 items.

How Can You Remember More in Short-Term Memory?

You can increase what you remember in short-term memory using a trick called chunking. This means grouping individual pieces of information into larger, more meaningful "chunks."

For example, if you need to remember a ten-digit phone number like 1234567890, it's much easier to remember it as three chunks: 123-456-7890. Your brain sees three chunks instead of ten separate digits, making it easier to hold in your short-term memory. This is why phone numbers are often displayed in groups!

Short-term memory mostly relies on how things sound (an acoustic code) to store information, and less on how they look. For instance, if you hear a list of letters, you're more likely to mix up letters that sound similar (like E and P) than letters that look similar.

What is Long-Term Memory?

Unlike sensory and short-term memory, which have very limited space and time, long-term memory can store a huge amount of information for a very long time – potentially your entire life! Its capacity is practically endless. For example, you might remember a new phone number for only a few seconds (short-term memory), but you can remember your home phone number for many years because it's stored in your long-term memory.

While short-term memory often uses sound to remember things, long-term memory tends to store information based on its meaning (this is called a semantic code). So, if you're trying to remember a list of words, you're more likely to mix up words that have similar meanings (like "big," "large," "huge") in long-term memory.

Types of Long-Term Memory

One important part of long-term memory is episodic memory. This is your memory for specific events that happened to you, including "what" happened, "when" it happened, and "where" it happened. Episodic memory lets you recall personal experiences like your last birthday party or a family vacation.

How Does the Brain Store Long-Term Memories?

Short-term memories are held by temporary patterns of brain activity, especially in the front and side parts of your brain (the frontal lobe and parietal lobe). Long-term memories, however, involve more lasting changes in the connections between brain cells, spread out across many parts of the brain.

The hippocampus, a small part of your brain shaped like a seahorse, is super important for turning new information from short-term into long-term memory. It doesn't actually store the memories itself, but it acts like a temporary processing center. Scientists learned a lot about the hippocampus from a famous patient named Henry Molaison, who had parts of his hippocampus removed and then couldn't form new long-term memories.

Some research even suggests that long-term memory storage might involve changes in your DNA!

Understanding the Multi-Store Model of Memory

In 1968, two scientists, Atkinson and Shiffrin, came up with a way to explain how memory works, called the multi-store model. This model suggests that memory flows through three main stages:

1. Information first enters your sensory memory.
2. If you pay attention to it, it moves into your short-term memory.
3. If you practice or repeat the information (this is called rehearsal), it can then be transferred into your long-term memory.

However, this model has been criticized for being a bit too simple. For example, we now know that long-term memory isn't just one big storage unit; it has different parts, like episodic memory (for events) and procedural memory (for skills, like riding a bike). Also, we can sometimes remember things without constantly repeating them, which the model didn't fully explain.

Research has also shown that short-term memory isn't just one single unit. For instance, a patient named 'KF' had brain damage that affected his ability to remember sounds (like spoken numbers) in his short-term memory, but his visual short-term memory was fine. This suggests that our short-term memory might have separate parts for visual and auditory information.

Exploring the Working Memory Model

The working memory model

Because the multi-store model was a bit too simple for short-term memory, two other scientists, Baddeley and Hitch, proposed the working memory model in 1974. This model describes short-term memory as an active workspace where we not only store information temporarily but also actively process and manipulate it.

The working memory model has three main parts, plus one added later:

• The Central Executive: This is like the boss of working memory. It controls your attention and decides which information to focus on and send to the other parts of working memory.
• The Phonological Loop: This part deals with auditory (sound) information. It's like an inner voice that silently repeats sounds or words to help you remember them, like when you repeat a phone number to yourself.
• The Visuo-Spatial Sketchpad: This part handles visual and spatial information. It's what you use when you're trying to imagine how many windows are on your house or figuring out directions.
• The Episodic Buffer: (Added in 2000) This part connects information from the other working memory components and links it with your long-term memory. It helps you create a complete picture of an experience, like remembering a story or a movie scene in chronological order.

This working memory model helps explain why it's easier to do two different tasks at once (like listening to music and drawing) than two similar tasks (like reading and listening to a podcast). Working memory is essential for our everyday thinking, learning, and problem-solving.

Related pages

• Performing music from memory

Images for kids

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See also

In Spanish: Memoria (proceso) para niños