The Unique Role Of Episodic Memory In Recalling Past Life Events

Episodic memory generally refers to your personal recollections of events, situations, and experiences in your life. It tends to be subjective and can involve personal memories, facts, events, general impressions, and snapshots. Episodic memory can be negatively impacted by trauma, vitamin deficiencies, Alzheimer’s disease, and other conditions. Therapy can often be helpful for those experiencing challenges related to memory and mental health.

What is episodic memory?

How episodic memory fits into the memory system

We may constantly use our memory, and remembering can be almost as automatic as breathing. We often don't realize when our memory is at work, instead focusing on the few critical things we forget rather than recognizing the many things we remember. Memory often allows us to recognize people we know and can enhance connections and histories with friends and loved ones. It may solidify the experiences that have shaped us and made us who we are. Memory can also help us navigate important information like names, numbers, and directions.

In general, there are two basic types of long-term memory: implicit and explicit. Implicit memory can be defined as something you remember without being consciously aware of it, like knowing how to read or play the guitar. Explicit memory typically requires conscious thought to recall. Under the umbrella of explicit memory are usually two smaller categories: episodic and semantic. In some ways, episodic and semantic memory can be connected and intertwined. 

Remember that episodic memory can be viewed as the recollection of situations, events, and personal experiences. Semantic memory can be defined as a structured remembering of factual information. These facts are usually not personal to you; they may instead be part of a universal group of knowledge. Knowing the alphabet and the names of colors, birds, and flowers can be examples of semantic memory.

While semantic memory can be objective, our episodic memory system tends to be subject to our interpretations and emotions. Episodic memory can explain why two people who have the same experience may recall it differently. Much of the act of remembering can involve the task of “encoding”: translating the memory into a format that makes sense in the context of your previous knowledge and experience. Because each person tends to be unique in the phenomenological aspects of their experiences, they may encode memories of the same events differently.

Origins of the term episodic memory

The term “episodic memory” was introduced by Endel Tulving in the 1970s as part of his foundational work on human memory systems. His research ultimately reshaped how psychologists understand memory, emphasizing that episodic memory involves conscious recollection and a sense of reliving past events rather than simply recalling facts. 

In his research, Tulving said of episode memory, “Remembering past events is a universally familiar experience. It is also a uniquely human one. As far as we know, members of no other species possess quite the same ability to experience again now, in a different situation and perhaps in a different form, happenings from the past, and know that the experience refers to an event that occurred in another time and in another place.”

Tulving also believed that while non-human animals “can learn, benefit from experience, acquire the ability to adjust and adapt, to solve problems and make decisions,” but “they cannot travel back into the past in their own minds.”

Different kinds of episodic memories

Episodic memories can be complex, and they may take many forms.

Time, place, and emotion

Episodic memory can comprise time, place, and emotion, which together shape how we recall life experiences. Tulving referred to this as “mental time travel.” In other words, it can be seen as the ability to revisit past events as if reliving them. This can mean that memories are not just remembered but re-experienced, combining the sensory details and emotions to create rich, personal recollections.

Autobiographical perspective

Autobiographical episodic memories can include basic information, like names and dates that are important to you. Some examples could be the name of your alma mater and the address of your first home. Memories of specific events, including particular moments from your personal history, such as the birth of your child or your ninth birthday party, can also be considered episodic memory.

Some episodic memories may be referred to as snapshots. These may be moments when you find out startling news. It may have been a significant life event, such as the birth or death of someone close to you. For some of us, historical moments like the Kennedy assassination, the Challenger disaster, or the 9/11 attacks may live in our minds in photographic detail as snapshots or flashbulb memories.

Episodic memory and the brain

With thousands of hours of experience logged in our brains, the number of experiences we remember can be surprisingly few. How is it that so many everyday events are forgotten, while a select few live on in our consciousness as episodic memories? As it turns out, the process of remembering is usually quite complex. Several tasks typically need to happen to form episodic memories. These usually include the following:

• Encoding: The brain may convert the memory into a format that can be easily stored and recognized. Encoding may be in the form of a visual image or the repetition of specific words or phrases.
• Storage: After encoding, an experience can usually only remain in your short-term memory for about 20 seconds before the brain forgets it. If you rehearse or repeat the memory, it typically gets filed away and organized in your long-term memory for later use.
• Retrieval: This is generally what you do when you recall an event or experience, usually by achieving the image or the words you used to encode it.

Forgetting can be the natural result of your brain not encoding or storing a memory. When a memory is not rehearsed or obtained, it usually fades away.

The area of the brain that binds memories to specific emotions may be the amygdala, which is a brain region where emotions are usually processed. On the other hand, the binding of more neutral memories normally occurs in the hippocampus, a part of the medial temporal lobe involved in learning. For example, the left hippocampus is specifically associated with the encoding and retrieval of verbal episodic memory.

Memories stored in the amygdala may tend to be much more resistant to forgetting than those stored in the hippocampus. Therefore, a routine day may be much more easily forgotten because it usually lacks strong emotional content. However, the day you experienced a terrible car accident or the day your child was born will more likely live on in your memory because of their associated emotions. 

Episodic memory across the lifespan

Episodic memory can change across the lifespan due to various factors, including neurological development, cognitive growth, and other changes that come with aging. 

The development of episodic memory and age changes

Early memory formation is likely connected to brain maturity. Memories from early life are typically forgotten quickly, and the ability to store and recall episodic information improves with age. Some research suggests that people’s earliest memories are from between ages 3 and 4.

As we age, episodic memory declines. Deficits in episodic memory do not always signal a problem; however, in some cases, they can signify a more serious problem.

What affects episodic memory function?

As mentioned, some changes in episodic memory can occur with age, but other factors can affect it as well. We explore some of them below.

Stress and trauma

Stress and trauma can impact elements of episodic memory in a number of ways. Some research suggests that the timing of a stressful event can affect how well it is remembered, with recall being particularly impaired when stress occurs just before retrieval. Research also suggests that trauma-related stress may cause episodic memory loss that goes beyond the traumatic event itself, with studies showing that those with PTSD have more significant memory deficits than controls.

Neurological and health conditions

Some illnesses and conditions can adversely affect your episodic memory. Here is a partial list:

• Vitamin B1 deficiency
• Subarachnoid hemorrhage
• Brain tumors
• Hashimoto’s encephalopathy
• Hydrocephalus
• Alzheimer’s disease

You may have challenges with episodic memory if you have difficulty remembering events and experiences, even if they happened recently. In addition, memory problems can affect your relationships with others who expect you to join in recalling experiences. Due to the diverse factors involved in recalling events and information, people with memory problems should generally consult with their doctor to help them diagnose the cause. 

Strengthening and supporting episodic memory

Research suggests that various factors can influence episodic memory. Some ways to improve it may include: 

• Engaging in higher levels of physical activity
• Engaging in higher levels of social activity
• Engaging in high levels of leisure activity
• Improving sleep quality

In some cases, a therapist or psychologist can help people who experience memory loss as a result of aging, illness, or dementia. A therapist can teach them compensatory skills for coping with memory problems and provide emotional support to manage the effects of memory loss. In addition, people with memory loss, as well as their loved ones or caregivers, may benefit from support groups where they can discuss their experiences with people who have similar challenges. 

For people whose memory is affected by depression, anxiety, or post-traumatic stress disorder (in which memories may “pop up” as intrusive flashbacks or nightmares), cognitive behavioral therapy can be a common treatment option used by therapists, both online and in-person.

Benefits of online therapy

For people whose symptoms or schedules make traveling to an in-person session difficult, online therapy can offer a convenient alternative. Sessions held on the BetterHelp platform, for example, typically require only a smart device and a stable internet connection. An online therapy platform can also make it simple to connect with a therapist who has helped others with memory-related concerns.

Effectiveness of online therapy

According to a 2020 study, individuals with mild cognitive impairment generally experienced improvement in their memory, language, and visuo-constructional abilities after participating in online therapy. This study joins many others, suggesting that online therapy is just as effective as face-to-face therapy.