All about the 3 types of memory and how they form

Deadlines. Birthdays. Errands. 

Every day, you have countless tasks and pieces of information to remember. And as your brain recalls how to write a cover letter or what stops to hit on your drive home, you pull from different types of memory. 

Short-term memory helps you hold onto new pieces of information as they come at you, like your coworker teaching you how to navigate new software. Procedural memory helps you perform different actions or skills, like filling out a priority matrix. And long-term memory stores the important information that makes you, you, whether it’s from an hour or 20 years ago.

With careful concentration and practice, your memory can improve. If you struggle with certain types of memory, learning more about them is the first step in improving your cognitive abilities and taking care of your mind. 

Understanding memory

Memory is the cognitive function that lets you categorize, store, and retrieve information. And building your memory is a continuous learning process, forming the framework with which you make sense of the world. 

Your ability to create and access your memory informs every decision you make throughout the day — both conscious and unconscious. From performing daily tasks to understanding nonverbal communication and everything between, your brain uses memory functions to guide decision-making and differentiate the things you know and the things you don’t. 

How many types of memory are there? 

There are three types of memory in psychology: sensory, short-term, and long-term. Each type of memory has its own characteristics, and some break down into subcategories.

You unconsciously control your sensory memory, like following your commuter route without deliberately thinking about making every turn. Your brain already knows, and can sense, where to go without you thinking about it.

Your short-term memory only retains small amounts of information at a time, while your long-term memory’s storage capacity has no limit. Several types of long-term memory follow further subcategories, like semantic memory, which is the general knowledge you can willfully recall. 

Differences in learning and human memory capacity

Neuroscientists and behavioral psychologists have long hypothesized about how memory works on an individual level. If a colleague’s ability to troubleshoot a problem or learn something new has ever impressed you, you’ve likely asked yourself how to improve your cognitive skills and do the same. 

Although there’s still a need for further studies, research shows that your ability to store information and develop expertise boils down to long-term motivated learning. In other words, the more time and attention you dedicate to learning a skill or piece of information, the stronger your memory will become. While natural cognitive decline, mental health issues, or developmental disorders can impact your cognition and memory systems, practicing over long periods is often more important than your IQ’s natural skill.

To improve a hard or soft skill, building up your intrinsic motivation, scheduling regular practice into your calendar, and maintaining your physical and mental fitness are all integral to your learning process. Like all other practices, building your memory takes time.

What are the types of memory?

The different types of memory are sensory, short-term, and long-term. Researchers categorize these by duration, capacity, and the type of information they store. Here’s more about each one:

Sensory memory

Your sensory memory stores sound, smell, touch, sight, and taste. It typically takes less than a second to recognize sensory information, like the sound of a Slack notification or the taste of a food you love. Your sensory memory makes the sound or sensation linger for a brief moment before fading away when it’s no longer relevant. 

All day long, sensory information overloads your brain, and it discards most of it. But when something grabs your attention, your brain transfers the information to your short-term memory or long-term memory. If you get a whiff of your coworker's coffee, it may stick in your short-term memory and encourage you to make yourself a cup. And if your coworker always makes an after-lunch coffee at 1 pm sharp, you may recognize the pattern and store the routine in your long-term memory. 

Short-term memory

Also known as your working memory, your short-term memory is your ability to hold onto small amounts of information for a short period of time. 

Imagine your short-term memory as your mind’s notepad. As visual and auditory stimuli come in, you consciously record information and act upon it. Remembering feedback a coworker gives you before writing it down, or glancing at an email address before typing it out, both use your short-term memory.

Studies show that people with high processing speeds in their short-term memories can process up to 25–30 pieces of information per second. And as your brain takes everything in, it goes through a process called chunking — transforming small pieces of information into more manageable chunks. If your manager gives you a phone number for tech support, your brain transforms 1234567890 into 123-456-7890. It processes each chunk as a single unit of information, making it easier to remember.

Long-term memory

Your long-term memory is the final stage of memory storage. It’s the ability to almost indefinitely store events, skills, and procedures, like childhood moments or important work processes.

If your short-term memory is your mind’s notepad, your long-term memory is the library where you store past notebooks. Continuous learning and repetition turn information into long-term knowledge, which builds your skill set and expertise. It sticks in your brain for longer periods of time, even if you don’t remember it forever.

According to Scientific American, your brain has about 1 billion neurons, which are the nerve cells that send messages throughout your body to do everything from inhaling to speaking. Although psychologists and neuroscientists haven’t figured out how to calculate the size of memory, if your brain were a DVR, you’d have enough space to view more than 300 years of television continuously. 

Long-term memory has several subcategories: 

Procedural memory

Procedural memory refers to encoding habits and skills through repetition. Repeatedly exposing yourself to the same information and stimuli consolidates them in your memory until you can automate them yourself, which is why they’re closely connected to motor skills. You use your procedural memory in daily activities like typing on a keyboard or driving a car. 

Procedural memory is implicit memory, an unintentional recall of information. It includes the things you’ve learned in-depth and can now do without thinking. A graphic designer who uses Photoshop daily will likely be able to go through a quick step-by-step photo editing process, using their procedural memory to do so. But a graphic design student with less experience may have to refer back to tutorials or ask for help because they haven’t built that foundation yet.

Explicit memory

Your explicit memory, or declarative memory, is your ability to intentionally retrieve information.

Imagine your manager pops by and asks you to fill them in on feedback from a client. You reflect on your meeting, reformulate the conversation, and recall specific comments and instructions. During that process, you access your explicit memory.

Explicit memory has two subcategories — episodic and semantic:

1. Episodic memory: Sometimes referred to as autobiographical memory, episodic memories refer to events that you’ve personally experienced. It includes a conscious awareness called autonoetic awareness, a type of self-knowledge that helps you imagine past experiences and create visions of future ones. Imagine a time that you received public gratitude from your manager. Using your episodic memory helps you recall the joy and pride you felt and motivate you to engage more with your work.

2. Semantic memory: Semantic memory is a broad type of memory that concerns general knowledge, ideas, and facts. Imagine the word “precedent.” A lawyer will understand the conceptual meaning and importance of the law precedents in arguing cases, and they may recall facts about specific precedents while searching for relevant arguments for a specific case. 

Procedural versus explicit memory

If you’re still unsure about the difference between procedural and explicit or declarative memory, here are the primary differences:

1. Procedural memory is implicit, meaning you recall it unconsciously. Declarative memory is explicit, meaning you recall it consciously. 

2. Procedural memory happens gradually through repetition. Declarative memory happens with a single exposure to information. 

3. Procedural memory typically happens through repetitive action. Declarative memory comes from understanding ideas and concepts. 

Imagine a librarian. Their declarative memory is what allows them to remember the names of specific books when they’re stacking shelves. But their procedural memory of the Dewey Decimal System helps them find exact locations in the library because they’ve used that system so many times. 

How are memories formed?

Each type of memory forms in the same way: your brain encounters information and stores it somewhere for later. It’s the details within that process that differ between the types. Here’s a brief breakdown of the three stages of memory formation:

1. Encoding

Your brain starts by retrieving, identifying, and priming information so it’s ready for storage. You encode information using four different methods — visual, acoustic, semantic, and touch — before deciding what’s important to remember. You likely discard background noise in your office, whereas a notification on your phone may reverberate in your mind, grabbing your attention and prompting you to act. 

2. Storage

The brain determines how, where, and for how long your memory stores information during the storage stage. Encoded information initially moves from your sensory memory to your short-term memory. But it might travel further into your long-term memory if it’s important or grabs your interest. 

Imagine working on a project with a coworker, and they suggest an edit on your draft of a job report. You store the information in your short-term memory to make the edit. It might slip away if you don’t give their instruction more thought. But if you spend time reflecting on their comment and how they can apply to future work, you may recall their constructive feedback while working on future projects to avoid similar mistakes. 

3. Retrieval

How readily you access information depends on the type of memory. You usually retrieve short-term memory is retrieved in the order you stored it, like each letter of a coworker’s email address. But you usually retrieve long-term memories by association, like the pattern your company uses to create employee emails. 

Total recall

The mind is a mysterious place. Although science hasn’t yet defined important aspects of memory — like the size of different types of memory or why some disappear, and others don’t — understanding the importance of your systems can motivate you to take care of it. 

Your memory forms the basis of your identity. It helps you walk, talk, and interact with the world around you. Through continued learning, physical exercise, and self-care, you can improve your memory and prime your mind for long-term health.