Understanding how your brain stores and retrieves information can transform the way you learn and remember. Research reveals that people have two distinct types of memory systems, each serving different but crucial functions in how we process and retain knowledge.
Drawing from the work of learning experts and neuroscientists, this exploration breaks down the fundamental differences between working memory and long-term memory. You’ll discover why some people seem to learn quickly, how your brain encodes different types of experiences, and practical strategies for strengthening your memory systems to become a more effective learner.
Table of Contents
The Two Kinds of Memory
While all memories form using the same fundamental process (neurons making connections with one another), Oakley, Rogowsky, and Sejnowski explain in Uncommon Sense Teaching that people have two distinct types of memory, each with different functions.
How Your Brain Encodes Memories
Before we jump into the two forms of memory, it’s important to first understand how the brain encodes memories in the first place. In Brain Rules, Dr. John Medina explains that, to form memories and therefore learn from experience, the brain goes through a complex process. Medina writes that the most important part of how memories work is encoding, which is how our brain processes and stores sensory information. Encoding happens in the first few seconds of having an experience.
When we take in new information, each of our senses processes it at the same time. For example, imagine purchasing a danish from a new bakery in your neighborhood. You’d see the display case of baked goods, you’ll hear the sounds of the customers and employees, you’ll feel the pastry you’ve been handed, and you’ll smell and taste the danish you’ve purchased. Each of these senses is processed by different areas of the brain, so all of this information is converted into electrical signals by neurons in their respective areas.
After memory encoding, the brain then stores the different pieces of information in the areas that they’ve been processed in. Instead of the memory of the bakery entering one particular spot in your brain, then, the various sensory information you’ve processed in the bakery will be dispersed all over the brain.
Automatic Versus Effortful Processing
Not all encoding is the same. There are two major types of encoding, automatic and effortful processing, which determine how easy or difficult it will be in terms of how the memories work with retrieving.
Automatic processing is encoding that requires very little conscious effort, usually involving a visual stimulus. For example, when you see a memorable movie, your brain will encode it automatically.
Effortful processing, on the other hand, requires conscious attention to form a memory. For example, when you study for a test, your brain uses effortful encoding. Effortful encoding can be challenging and requires numerous repetitions before you can easily remember what you learned.
Short-Term (Working) Memory
The first kind of memory is working memory, also called short-term memory. As the name suggests, this system is for knowledge you’re currently working with—either learning it or applying it to a problem. The authors say that working memory has an extremely limited capacity and can only hold about four pieces of information at a time. As new thoughts grab your attention and enter your working memory, they push out any pieces of information you’re not actively thinking about. If that information hasn’t yet been added to your long-term memory, you’ll forget it.
Think of your working memory like the CPU of your computer. It stores whatever your computer is working on at the moment, and only for as long as you need it. For example, if there’s a pigeon on the sidewalk, you only need to remember its existence long enough to walk around it.
Your working memory’s effectiveness depends in part on how well you can focus on a particular task. To illustrate this point, in ADHD 2.0, psychiatrists Hallowell and Ratey explain that people with ADHD are very forgetful due to difficulties with managing their working memory. Their minds work so quickly and get distracted so easily that their working memory is constantly cycling through new pieces of information rather than holding onto what’s relevant at the moment. In other words, people who struggle with working memory may not have a deficit in capacity, but a deficit in concentration.
Differences in Working Memory
Although a person’s working memory can hold about four pieces of information, Oakley, Rogowsky, and Sejnowski clarify that this is only an average—some people can hold six or more items in their working memory simultaneously, while others struggle to manage even three. Note that this is purely due to neurological differences and has nothing to do with intelligence or effort.
If you have a relatively large working memory capacity, then you can process a lot of information very quickly—you’re probably the first one to come up with an answer to a question or problem. However, the authors warn that such mental efficiency can also work against you. Things seem to come very easily to you, and you’re likely to think that you understand topics before you’ve put in sufficient study. As a result, you might fail to build up strong long-term memories and find yourself unable to retrieve that knowledge later.
On the other hand, if you have a smaller working memory capacity, you may appear to be a slow learner: You can’t immediately use what you’re learning, and you might take longer than your peers to solve problems. However, the authors say that people with smaller working memory capacities tend to develop robust and flexible long-term memories. After all, if a topic doesn’t immediately seem clear to you, then you’ll likely feel the need to keep reviewing and practicing it. So, while you might not seem to think as quickly as most people, your memory is probably much more reliable.
| Working Memory May Explain Different Types of Intelligence This discussion of differences in working memory closely resembles the two types of intelligence that Arthur C. Brooks talks about in From Strength to Strength. Citing the work of psychologist Raymond Cattell, Brooks says that we all have two distinctly different methods of solving problems, and that our capacity for each method changes as we age. According to Brooks, young people tend to have very high fluid intelligence, which he describes as the ability to innovate, make new discoveries, and come up with creative solutions to problems. This is very similar to the effects of having a high working memory capacity that Oakley, Rogowsky, and Sejnowski describe. However, Brooks asserts that fluid intelligence starts to decline once people reach their 30s or 40s, and therefore they rely more on crystallized intelligence: the accumulated knowledge they’ve gathered over their lifetime. This mirrors how people with low working memory capacities tend to form strong long-term memories and rely on their ability to recall whatever they need to solve a problem. Therefore, one could conclude that fluid intelligence relies on working memory, while crystallized intelligence relies on long-term memory. Scientific research supports this connection, as studies have shown that working memory capacity declines with age, just as Brooks argues fluid intelligence declines. On the other hand, it’s only natural that people develop more long-term memories as they get older (barring cognitive deficits, like those resulting from brain damage and dementia). |
Long-Term Memory
In contrast with working memory, long-term memory can hold vast amounts of knowledge, and can do so for many years if the neural connections are strong enough. However, this type of memory only acts as a storage system—your working memory has to retrieve the information from long-term storage to use it.
For example, you’ve probably had times when you’ve forgotten why you came into a room. This happens when you have a specific piece of information in your working memory (the reason you went to that room), then something distracts you so that you stop thinking about it. Once that reason is gone from your working memory, you’ll struggle to remember it and may need to retrace your steps from the last thing you do remember: the most recent piece of information that made it into your long-term memory.
If you want to store knowledge in your long-term memory, the authors suggest using retrieval practice: Try to actively recall information without looking at notes or other reference materials. For example, you might try explaining a concept to someone else, solving problems from memory, or writing a summary of the key points you remember about a topic. Such practices will also serve to strengthen the relevant connections, helping you recall that information more easily next time.
What Part of the Brain Controls Long-Term Memory?
The study of memory necessitates the study of the brain. Memories are created in, stored in, and affected by different parts of the brain:
- Neocortex. This is the brain’s wrinkly-looking outer layer. It stores memories.
- Hippocampus. This is involved in converting our perceptions into long-term memories. The right posterior section is involved in spatial navigation, which, as we’ll see, is an important aspect of memory.
- Medial temporal lobe. This contains the hippocampus and is involved with long-term memory.
- Basil ganglia. This is involved in learning habits.
- Cerebellum. This is involved in learning motor skills.
- Frontal and parietal cortices. These are involved with recalling long-term memories.
When we use our brains, they physically change—we can form new neurons and rearrange connections. This is known as neuroplasticity. For example, neuroscientist Eleanor Maguire studied the brains of London cabbies-in-training. She found that their right posterior hippocampi (responsible for spatial navigation) were 7% larger than the average person’s because they spent so much time memorizing the layout of the city. This is a fascinating insight into what part of the brain controls long-term memory.
“Knowledge Collapse” Occurs Before Creating Long-Term Memories
In A Mind for Numbers, Barbara Oakley describes the difficulties of how long-term memories work and one particular pitfall of long-term memory.
This pitfall is called knowledge collapse. As you learn more about a subject, your neurons will sometimes have to rearrange themselves in order to store the new information. This can temporarily wreak havoc on retrieving your long-term memories about the subject: As restructuring occurs, it becomes suddenly difficult to remember information you thought you solidly knew.
However, this is a temporary problem, as this restructuring ultimately helps you learn new and complex information. If you experience knowledge collapse, instead of stressing and giving up, keep up with your learning until your brain has integrated the new information.
| Additional Types of Memory In addition to working memory and long-term memory, Lisa Genova in her book Remember, names three additional memory types: Episodic Memory: Episodic memory refers to your memories of things that have happened. These include experiences like important life events and specific memories of things that have happened to you. Semantic memory, on the other hand, is fact-based knowledge not linked to a specific personal experience. This includes things like your vocabulary (remembering what words mean and how to use them) and general knowledge. Prospective Memory: Genova also describes prospective memory, which is your memory of things you intend to do in the future. For example, if you plan to call your doctor at a certain time, remembering to do this when the time comes requires you to use your prospective memory. Episodic, semantic, and prospective memory are all types of declarative memory, or memories that you can consciously retrieve at will. Muscle Memory: Finally, Genova discusses muscle memory, which she describes as the ability to remember how to do something. Like episodic memory and semantic memory, it’s a type of long-term memory. But, unlike the previous three we’ve discussed, muscle memory isn’t a type of declarative memory. Instead, you activate it unconsciously when you do something you’ve done many times before. For example, you don’t have to re-learn how to type every time you sit down in front of the computer: Your brain retains the information of how to move your body to achieve the desired result. Despite the name, muscle memory isn’t stored in your muscles, but in your brain. |
Dive Deeper Into Your Memories
If you want to learn even more about the two kinds of memories and how your brain works, check out the full guides to the books mentioned throughout this article here.
