Short-Term and Long-Term Memory (What it is & How to improve it)
We’d all like to improve our short-term memory & long-term memory in some capacity, but to understand how to do that, we have to know how it works, why it fails, and what we do in our lives that has an impact on it. If you’re looking to understand how to enhance your memory as well as protect it, this is the blog post for you.
What is the long-term memory?
Put simply, exactly what it sounds like — the retention of knowledge over a long time. Since short-term memory, which we will get to in a second, is quite short, long-term memory refers to recalling information anywhere from a little over a few moments ago to an event that happened years and years ago.
The more significant your brain considers the information, the easier it will be to recall — examples include your best friend’s birthday, a particularly embarrassing moment, the birth of a child, the first time you met your spouse etc.
Part of this is due to the fact that the more you access memories, the easier they are to remember. Like the old saying “use it or lose it,” retrieving your memories more often consequently reinforces the neural networks that are responsible for keeping and accessing the information.
It is this repeated access that helps short-term memory evolve into long-term memory, and lack of repetitive access that can lead to long-term memories being lost (1).
What is Short-Term Memory?
Short term memory’s defining characteristic is that it is temporary. It’s also a lot shorter than you think — if you don’t make a conscious effort to maintain, retrieve, or practice short-term memory, it probably won’t last more than 30 seconds, maybe a minute if you’re lucky.
Short-term memory is also known as “active memory” because you only truly remember it at the moment. For example, if someone quickly tells you about a list of to-dos, you might ask them to repeat it a minute later because you forgot some of the items.
You can increase the likelihood that you remember the information for longer by repeating it mentally or aloud, but generally, your short-term memory can only hold about 5-9 items, although new research is showing that other factors dictate capacity.
Since you can only remember so little for such a short time, it’s very easy to lose short-term memories due to interference theory, in which any new information pushes out the old data.
Short-term memory is not the same as working memory, however, although the two terms are often falsely used interchangeably. Working memory is not the actual memories, but the operations your brain performs to keep, arrange, and deal with information.
Short-term memory can be transformed into long-term memory through “chunking,” which helps break up information into easier-to-remember segments, repetition/rehearsal, and possibly exercise (2).
Wait, so how does my memory work?
For starters, there are two types of memory — explicit and implicit.
Explicit memories are memories in your consciousness, such as episodic memory (moments/events in your life) and semantic memory (knowledge about the world, such as the information you study for a test).
Implicit memories, on the other hand, are usually considered unconscious because they are ingrained in your body. For example, once you learn how to ride a bike or use a cell phone, you do those actions unconsciously.
Now, your brain initially accepts information as short-term memory and saves some of it to long-term.
Overall, your memory is run by three overarching processes — encoding, storage, and retrieval. They each do pretty much exactly what it sounds like they would.
As such, your memory is influenced by how these processes work and are affected.
For example, being more present when information is encoded (i.e., well-rested, attentive, etc.) will result in a stronger encoding process and more vivid memory. Each time you retrieve a memory, the memory is affected because it gets re-encoded by another set of neurons.
Usually, this means a stronger memory, but there is a possibility that small aspects are changed or weakened depending on how it is retrieved. (3).
How do I improve it?
Now that you know the basics of how your memory works, you’re probably wondering how you can improve your memory beyond tricks like mneumonics.
We know creating lasting memories well depends on strength, speed, and the ease with which your brain makes neural connections as well as how you alert during the time of encoding. So lets at look what can set you up for optimal memory encoding, storing, retrieving, and protecting.
Can you eat your way to a better memory?
If by eat your way you mean incorporate foods that protect your brain and support neurogenesis, then yes. Neurogenesis-supportive foods help your brain make new connections; the speed and strength with which your brain makes these connections play a significant role in supporting short-term memories and making the connections that create memories last longer.
Since neurotransmitters are responsible for pretty much everything the brain does, foods that boost neurotransmitters are also crucial to incorporate. So what foods should you be eating to boost your memory?
A lot of foods from our brain booster list apply, such as:
- DHA omega 3 fish oil rich foods such as low mercury, fatty fish
- Dark chocolate
- Supplements in case you have deficiencies
- Sea vegetables
- Extra virgin olive oil
- Gut-friendly foods (pro and prebiotics — which you can read about here):
- Green tea
However, we have some new additions for you as well. For example, certain nutrients play a key role in supporting your temporal lobe are essential.
A 2004 study published in the American Journal of Clinical Nutrition showed that folate deficiency might raise the risk of developing Alzheimer’s disease (4). Foods rich in folate include spinach, asparagus, beef liver, black-eyed peas, brussels sprouts, and avocado.
Moreover, because B6 helps the brain make serotonin, and many numbers of nerve cells within your temporal lobe rely on serotonin for proper communication, vitamin B6 is essential to keep your temporal lobe functioning smoothly.
Munch on chickpeas, beef liver, salmon, and chicken to get your B6, or add some nutritional yeast to your diet to get your B6 fix.
There are also certain herbs that may help boost your memory power.
Sources of Apigenin — Parsley, Celery, Chamomile Tea:
Apigenin is a compound that supports neurogenesis (5). Some of the best sources include chamomile tea, celery, and parsley (6).
Panax Ginseng + Gingko Bilboa:
The combination of the two has been shown to boost memory in healthy adults (7). Specifically, the combo improves long-term episodic memory (8), working memory (9), and warded off age-related memory loss in middle-aged volunteers (10).
Panax Ginseng releases Nitric Oxide (NO) which fights oxidative stress and thus protects the brain (11). Moreover, Panax Ginseng raises levels of important neurotransmitters, such as serotonin (10), dopamine, epinephrine, and norepinephrine involved in learning (11).
A UC Irvine study showed that in conditions where you usually wouldn’t be able to encode and create new memories well, exercise and sodium butyrate could shift the situation from one of subthreshold learning to one where the brain is primed for plasticity (learning) (16). Sodium butyrate can boost long-term memory by promoting synaptic activity in the hippocampus (17).
Butrayte also increases BDNF (18) and promotes nerve tissue growth and development (19). Your gut can create butrayte when it digests and ferments foods like whole grains, fruits, and vegetables — yet another reason to eat healthy (20).
Habits for Better Memory:
However, eating the right foods can only do so much, which is why improving your memory includes creating good habits.
Sleep is quite literally when memories are made.
While you snooze, your brain converts memories from short-term storage into long-term storage, preparing for the next day (25).
A Duke University study found that visual short-term memory capacity dropped following sleep deprivation, logically due to a lack of ability to focus (26).
Since we know attentiveness plays a key role in encoding memories well, it might do your memory good to get more sleep (although sleep does a lot more than that).
Dr. Sandrine Thuret, head of X Lab at King’s College, recently gave a Ted talk on how slight caloric restriction (20-30%) and intermittent fasting can help boost neurogenesis (growing more neurons). (27).
This may be because caloric restriction lowers inflammation and increasing BDNF (28). Mark Mattson, a neuroscientist at the National Institutes of Aging, does mention that older adults are at a higher risk of nutrient deficiencies, and could experience health problems that outweigh the potential benefits if they cut back on calories too severely.
It’s important to note that “Not everyone is going to benefit from calorie restriction,” he says. But for those who are already consuming more than they need, there’s yet another health reason to cut back beyond weight loss (28).
Chew your food:
Random as it sounds, chewing your food seems to be better for brain growth, which of course also helps out your memory. A study done in Japan found that soft-diet feeding (where the food was rendered into a powdered form thus not requiring chewing) lowered cell growth in the hippocampus (29).
Don’t overdo the saturated fats:
Healthy fats are essential for brain health, but as a UCLA study shows, a diet containing excessive amounts of saturated fat can impair neurogenesis (30).
Overall, memory is incredibly complex and governed by a lot of different factors. While improving memory seems out of reach, in eating foods that protect the brain and boost its function and creating habits that keep your mind running smoothly, you can help give your memory the best shot at working well and lasting for a long time.
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4304302/ (Not referenced in blog)
- https://www.ncbi.nlm.nih.gov/pubmed/17828627 (Not referenced in blog)
- https://www.ncbi.nlm.nih.gov/pubmed/14561278 (Not referenced in blog)
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257700/ (Not referenced in blog)