What Is Episodic Memory?
Episodic memory is a type of long-term memory. It helps you remember the time, place, and details surrounding a specific event or experience in your life. For example, remembering what you had for breakfast or where and when you started high school are episodic memories.
Episodic memory vs. semantic memory
These are both types of long-term memories that are key to how you function in daily life, but they serve different purposes:
Episodic memory is a personal record of events that have happened to you. Think of it as an internal diary or scrapbook. Some describe episodic memory as the ability to “mental time travel.”
Semantic memory refers to fact-based memories of basic information. This is impersonal knowledge anyone can learn. For example, knowing that apples and oranges are types of fruit is a form of semantic memory. So is knowing historical facts like the first or current U.S. president, or multiplication tables (2x2=4).
Here’s another way to think of it: Semantic memory is knowing what a bicycle or car is, but episodic memory is knowing who was around when you had a bad bicycle crash or what year you learned to drive.
Other kinds of memory include:
Emotional memory. Like the name suggests, this refers to a memory of a feeling. Your emotional memories can help you remember certain people, things, or places that have made you feel good or bad in the past.
Procedural memory. This is when you learn how to do a set of movements or actions without having to remember each step. Common examples include learning to ride a bike or drive a car.
Short-term memory. Also called working memory, this is the part of your mind that holds bits of information only for a short while. Multi-tasking involves working memory, as does thinking of someone’s phone number and then remembering it long enough to type it into your phone.
Episodic Memory Examples
Everyone’s episodic memories are unique. That’s because they capture the who, what, and when of events from your recent or long-ago (remote) past. These memories will likely be different from someone else’s, even if this person was part of the same experience.
Here are some examples of episodic memories:
- Details of your 16th birthday party
- A joke you heard and who told it to you
- Details of your first kiss
- What happened at a meeting a month ago
- What you had for dinner last night
- What street you were on when you had bicycle crash
Episodic memories may also include personal events such as:
- Where you parked your car last
- A conversation you had with a friend a month ago
- You first day of kindergarten
- Details of a holiday gathering
- What you had for breakfast today
Countless experiences fall under the category of episodic memories. The key thing to remember about these long-term memories is that they are personal accounts of your life.
How Episodic Memory Works
Several areas of your brain help you make episodic memories, including the following:
Hippocampus. As a part of the brain’s limbic system, the hippocampus helps you process emotion, learning, and memory. It helps you understand your surroundings (spatial memory) and transfers short-term memories into long-term storage. It also timestamps your experiences, allowing your brain to organize past events in the right order when you recall them.
Parahippocampal region. This area surrounds the hippocampus and sends memory-forming information to it, including the what and where of the event.
Amygdala. This is the part of your brain that processes emotions. Experiences that activate the amygdala tend to stick around longer than neutral ones. This means it may take you longer to forget emotionally-tinged memories. These are things that make you happy, sad, afraid, or angry.
Prefrontal cortex. This area is thought to be the driver’s seat of your consciousness. Your hippocampus and prefrontal cortex send information back and forth. This connection allows you to access memories in a way that helps you plan and carry out tasks.
Creating an episodic memory
Your brain goes through multiple steps to create an episodic memory. Here’s a breakdown of the process:
Encoding. Your brain gathers and processes details about what’s happening. This may include sensory information like your emotions or what you see, hear, and smell. Context is also important, including the time and place of an event.
Elaboration. This is any association that strengthens your connection to an experience, including strong emotions. Or maybe you use a trick to remember someone’s name (repeating the name in your head) or link the information to a long-term memory (the person has the same name as a family member).
Consolidation. This is when your brain takes a short-term memory and puts it into long-term storage. This part of the process can take days or weeks.
Retrieval. This is when you consciously remember things. Your ability to bring details of a memory to mind depends on how well your brain encoded and stored the information in the first place, as well as the kinds of cues (emotions, smells, sounds) you use to recall a specific event.
Episodic Memory Loss
You can’t expect to remember your life perfectly, especially as you get older. But certain things can lead to episodic memory loss that’s more than what’s expected for normal aging.
Certain medical conditions that affect your brain can result in episodic memory loss, including:
- Alzheimer’s disease
- Vascular dementia
- Mild cognitive impairment
- Dissociative disorders, including certain types of trauma-related amnesia
- Depression
- Schizophrenia
- Parkinson’s disease
- Huntington’s disease
Other neurological conditions that may affect your episodic memory include:
- Seizures (epilepsy)
- Multiple sclerosis
- ALS (Lou Gherig’s disease)
- Limbic encephalitis
- Traumatic brain injuries, including concussion
- Tumors or blood clots in you brain
Non-neurological medical conditions that might affect your memory include:
- Diabetes
- Ongoing low blood sugar
- Thyroid, liver, or kidney problems
- Obstructive sleep apnea
- Low levels of vitamin B12 or other key nutrients
- Serious infections
- Hormonal changes associated with pregnancy and menopause
Neurological diseases like Alzheimer’s disease are less likely to affect your remote memories, or the episodic memories you’ve had for a very long time. Experts aren’t sure why, but they think one reason is because distant long-term memories aren’t stored in the hippocampus.
But tell your doctor if you or a loved one start to forget important details about your life. They can run tests to look for hidden health conditions that might be affecting your memory. Be sure to discuss any medications you’re taking. Some can negatively affect memory..
How does stress affect episodic memory?
You may have trouble forming or recalling memories when you go through a stressful life event, including positive or negative experiences such as:
- Marriage, vacation, moving, or any big change
- Things that physically or emotionally threaten or harm you
- A job that’s too stressful for you to handle
- Something that stops you from achieving a life goal
- Death of a romantic partner, parent, or loved one
Episodic memory and trauma
Your hippocampus and amygdala are particularly sensitive to stress and trauma.
Strong emotions can enhance memories, especially during dangerous experiences like sexual assault or life-threatening situations. You may remember certain details around a traumatic event forever, which may help protect you from similar dangers in the future.
On the other hand, trauma can also interrupt the episodic memory process. You might not remember anything about a scary or highly stressful event, or you may only store bits and pieces of what happened. This phenomenon is known as dissociative amnesia, and forgetting is likely another protective mechanism.
Episodic memory loss is a key part of post traumatic stress disorder (PTSD). If you have PTSD, you may also have memory problems in other areas of your life, including things you see, hear, or feel during everyday events.
How to Improve Episodic Memory
You’re more likely to remember events in your life when you’re not distracted, so purposely pay attention to what’s going on around you when you want to form new memories. This’ll help your brain take in more information about your surroundings.
Here are some other tips to improve your episodic memory:
Exercise. Regular movement is good for brain health and memory, in general. But researchers have found that aerobic exercise may help episodic memory, particularly in those younger than 55 who don’t have dementia. That’s the kind of physical activity that gets your heart rate up.
Practice mindfulness meditation. This is when you pay attention to the present moment. For example, you focus on your breathing or the sights and sounds around you for a certain amount of time. Studies show this kind of meditation can help you store and retrieve episodic memories.
Give brain exercises a try. Researchers have found mixed results when it comes to how big of a difference brain training makes in episodic memory in healthy adults. But there’s no harm in trying exercises that challenge your memory.
Remember things on purpose. The more you replay or repeat the details of an event in your mind, the more likely you are to strengthen the process that encodes a memory.
Try using memory tools. This can mean saying something out loud or linking information to a picture, sound, smell, taste, or other sense. You can also use a mnemonic device. That’s when you use something like a phrase, set of letters, or rhyme to strengthen a memory.
Write things down. Studies show you’re better able to remember things when you write them by hand compared to when you take notes by typing on a laptop.
Eat nutritious foods. Researchers have found that flavanols – nutrients found in colorful fruits and vegetables, along with tea and cocoa – can increase blood flow to the brain and boost memory in young and older adults.
Fix vitamin deficiencies. People who are low in vitamins B1 or B12 are more likely to have memory trouble. Your doctor can give you a simple blood test to check your vitamin level and if a supplement might help you.
Get enough sleep. You may not be able to think clearly when you skimp on a good night’s rest. Sleep also seems to play a big part in how your brain sorts through and stores memories.
Takeaways
Episodic memory is a type of long-term memory. It helps you recall specific details of a past event or personal experience. This includes the what, where, and when of something that happened to you.
Regular exercise, following a nutritious diet, getting good sleep, and managing stress are everyday steps you can take to boost brain health and try to improve memory.
It’s natural to experience some memory loss with age. But tell your doctor if you or a loved one forget big details or mix up important life events. Some health conditions and medications can impair your episodic memory.
Episodic Memory FAQs
What triggers episodic memory?
Episodic memory is the ability to recall the specifics of a personal experience. These kinds of memories are often triggered by sights, smells, sounds, or other sensory information tied to that past event. Factual (or semantic) memories may also trigger an episodic memory.
Does anxiety affect episodic memory?
Memories linked to strong emotions tend to stick around longer than neutral events. As a result, you may have a better memory of scary things that happen to you. But people who have high levels of anxiety tend to remember fewer details about non-emotional experiences.
Why is my short-term memory so bad lately?
Stress, anxiety, and depression can hurt your short-term memory, which is also called your working memory. Certain health conditions, including thyroid problems, vitamin deficiencies, brain tumors, infections, or brain disorders like Alzehimer’s disease and other forms of dementia, can also have an impact on short and long-term memory.
How reliable is episodic memory?
No one remembers their life perfectly. It might be more accurate to think of episodic memories as stories your mind creates rather than snapshots of reality. But the reliability of an episodic memory depends on how well your brain encoded the information in the first place.
