Most people probably don't know (or care) that we have 7 different types of memory.
If your job involves critical tasks that require optimum cognitive functioning, however, you should know about how your brain processes new information, creates memories, and quickly recalls the necessary information when you make those critical split-second decisions.
In addition to directly impacting job performance, memory skills are also being incorporated into fitness-for-work measures (*cough* AlertMeter® *cough*) in order to track critical employees' cognitive functions and ensure that they are fit to perform their tasks safely.
So, here you go. Here are the 7 types of memory. You're welcome.
Image credit: Queensland Brain Institute
1. Short-Term Memory
Short-term memory only lasts 20 to 30 seconds. It stores information temporarily and then either dismisses it or transfers it to long-term memory.
It is also sometimes called working memory, although working memory is more specific to information that we receive, use quickly, then discard. For example, a phone number, a person’s name, or what you’re going to buy from the market are stored in your short-term working memory for just as long as it takes you to use it.
2. Long-Term Memory
Our long-term memories are a bit more complex than our short-term memories. Anything that happened more than a few minutes ago would be stored in long-term memory. Depending on how often we recall or use a certain piece of information, the strength of the memory varies.
Long-term memory is divided into explicit and implicit memories.
3. Explicit Memory
Explicit memories are a type of long-term memory which you remember after consciously thinking about it. For example, the name of your childhood dog or your best friend’s house phone number!
There are two types of explicit memory--episodic and semantic.
4. Episodic Memory
Episodic memories are a type of explicit memory that relate to our own personal lives. For example, a particularly exciting Christmas morning, the day you got married, or even what you had for dinner last night.
Studies have shown that autobiographical, or "episodic", memories aren’t necessarily accurate because we reconstruct them over time and they change and adapt to the new context in which we recall them.
Our ability to retain episodic memories depends on how emotionally powerful the experiences were.
For example, many people remember where they were and what they were doing when 9/11 happened. Not only would this involve a very powerful emotional reaction, you would probably also have been very focused as it occurred.
When our brains are extremely focused, it becomes easier to process and store sensory input which in turn makes it easier to later recall the experience.
5. Semantic Memory
Semantic memory accounts for our general knowledge of the world.
For example, the fact that the sky is blue, giraffes have long necks, and puppies are cute.
Unlike episodic memory, we are able to maintain the strength and accuracy of our semantic memory over time. As we age, it begins to decline slowly.
6. Implicit Memory
Implicit memory is the second major type of long-term memory. It comprises memories that you don’t have to consciously recall.
For example, riding a bike or speaking a language. Even though it may require a lot of conscious thought while learning, at some point it became implicit and you did it automatically.
In the 1990 movie Total Recall, Arnold Schwarzenegger dreamed of becoming a secret agent in Mars without consciously knowing that he actually was a secret agent in Mars before his memory was wiped and rewritten.
This subconscious attraction to espionage and other planets might have been a type of implicit memory for Arnold.
7. Procedural Memory
Procedural memory is a type of implicit memory allows us to do certain tasks without thinking about them.
Besides riding a bike, it also includes tying a shoe, brushing our teeth, or driving a car.
It is likely that procedural memory is stored in a different part of the brain than episodic memory because people who experience traumatic brain injuries often either forget autobiographical information or forget how to perform simple tasks like walking or feeding themselves.
Now that you know about each of the types of memory, here are some ways to keep each one in tip-top shape.
Methods to Sharpen Your Memory
Several studies have found that being tested for information helps create stronger memories.
For example, students who were repeatedly tested on a list of vocabulary words in a foreign language performed better on the final test than students who were given extra time to study.
This concept is known as test-enhanced learning and is based on the theory that repeated retrieval of information has a greater impact on the memory than longer study periods. This effect can be further enhanced by immediate feedback after each retrieval.
So, the next time you’re giving a presentation or teaching something, instead of lecturing your audience, ask them questions. Get their neurons to fire up and form new connections by making them continually retrieve the new information. Cement the new long-term memory by giving them immediate feedback.
You don’t need to be a child to enjoy feedback. Anyone can get a release of dopamine when they receive positive feedback.
I know we haven't shut up about sleep recently; however, as sleep expert and neuroscientist Dr. Matthew Walker said:
“Sleep is the greatest legal performance enhancing drug that most people are probably neglecting.”
While we sleep, our brains process and store long-term memories.
Find out more about the power of sleep here: 6 Ways Sleeplessness Affects Your Day.
During Rapid Eye Movement (REM) sleep, the brain replays memory sequences that we learned while awake, except 20 times faster. Through this process, memories are consolidated and stored for long-term use.
In addition to strengthening our memories, sleep also helps us learn new information.
Researchers found that students who were deprived of sleep after learning a new skill had a significantly weaker memory of that skill than students who received adequate sleep.
Not only will getting at least 8 hours a night help you learn and remember new information, it can also lessen the risk of developing Alzheimer’s as you age (according to Dr. Walker, see below).
3. Sensory Input
In addition to exercising your brain by frequently retrieving information, engaging all your senses with the experience also makes a big impact on how well you’ll remember it later on.
If you involve all 5 senses in the experience--if you can hear, see, smell, taste, and smell it--then you will be able to recall it better in the future.
Smells seem to be especially powerful in evoking strong, emotional memories. For me, the smell of petunias and jasmine flowers immediately transport me to my childhood summers while living in Turkey.
For some, the smell of fresh-baked cookies may carry them back into their grandma’s kitchen.
So, when improving memory, we must try to engage each sense as powerfully as possible. We remember experiences that smell amazing, look beautiful, taste delicious, or sound lovely.
We also remember horrible experiences--nearly freezing to death on a camping trip, getting food poisoning from eating something disgusting, or even seeing a really gruesome scary movie.
I accidentally saw Saw when I was young and will never be able to get the memory out of my head. If you don’t have the resources to make an experience powerfully pleasant, then you may remember it just as well by making it powerfully unpleasant.
4. Drink some coffee.
If you’re one of those people who need coffee in the morning before you do anything or talk to anyone, you’re probably a firm believer in the strong cognitive boost it offers.
Caffeine is one of the most popular cognitive enhancers in the world, and besides preventing drowsiness, it can enhance cognitive functions such as memory, motivation, or creativity. (Health.Harvard.edu)
Overuse and misuse of caffeine and other cognitive enhancement drugs can be dangerous and disruptive of your natural sleep cycle.
So, have your cup or two of coffee in the morning but limit caffeine 4-5 hours before bedtime.
A good night’s sleep will always be the safest and most effective cognitive enhancer.
5. Minimize Stress
Although we are more likely to remember a particularly stressful experience for a long time, attempting to learn or form new memories while under stress is rarely successful.
Stress alters the way our brains process information and how the memory is stored.
For a great way to minimize stress, see number 10.
6. Minimize Distractions
It may be obvious, but few people actually make the commitment to reduce distractions while attempting to learn new information or create new memories.
Instead of getting up for another cup of coffee or looking for new distractions to “clear our minds” or “switch it up”, our brains could function much more efficiently just by reducing noise, disabling digital notifications, and clearing clutter from our work/study areas.
Multitasking also counts as distraction. Although many people believe themselves to be quite adept at it, scientific studies have repeatedly proven that the brain actually rapidly switches between tasks rather than doing both simultaneously, thereby reducing the quality and efficiency of our performance in each task. Studies have also shown that multitasking impairs both long-term and short-term memory.
7. Smell rosemary
In a 2003 study, a group of volunteers were given a series of long-term memory, short-term memory, and attention and reaction tests.
Some of the participants took the test in a room infused with lavender oil, some took it in a room infused with rosemary oil, and others took the test scent-free.
Those who took the test in the rosemary scented room reported feeling more alert and performed significantly better on the memory tests than those in the unscented room.
Those in the lavender scented room performed the worst and reported feeling less alert.
Although more studies are required to confirm the alertness-inducing effects of rosemary, it wouldn’t hurt to test it out yourself in the meantime and deck your workplace out with a few new plants.
8. Eat well
Scientists recommend eating foods high in antioxidants to keep the brain young and maintain memory function as we age.
This is because antioxidants kill “free radicals” that enter our bloodstream before they can kill our brain cells.
These include blueberries, apples, bananas, dark green vegetables, garlic and carrots. Chocolate also has antioxidants called flavanols. However, eating too much of it can backfire and give you a sugar rush and crash instead.
In addition to antioxidants, the brain benefits extremely from healthy fats like Omega-3 fatty acids which are found in fish and nuts. So, try to be understanding when your coworkers come in smelling like tuna or peanut butter.
9. Chew gum
Similar to the rosemary theory, the gum chewing theory is one that does not guarantee results but wouldn’t hurt to try.
In a 2002 study, gum-chewers performed significantly better on tests of both long-term and short-term memory than non-gum-chewers.
Many studies since then have also identified a small but significant effect of gum chewing on memory and cognition.
Violet chewed too much gum. (Pinterest)
10. Play brain games
The more you use your brain, the better it will run. So, exercise it just like you would your body (and if you don't exercise your body, get that done too while you're at it).
There are many brain exercise programs on the internet that are quickly gaining popularity.
Lumosity, for example, was designed by neuroscientists to help aging people improve their memory, concentration, alertness, and even mood. You don’t have to be old to use it.
If you’re not into that, there’s always sudoku and crossword puzzles to keep your neurons on their toes.
A neuron on its toes. (clipart.email.com)
Even if you fill up your office with rosemary and chew more gum than Violet Beauregarde, you will be brain-dead without adequate sleep, a proper diet, and frequent exercise.
Scientists believe that increased blood flow to the brain, as well as the mild stress of exercising, may result in the production of growth factors in the brain leading to improved cognitive performance.
Recent research has shown that adults who walk regularly gain hippocampus volume (memory center of brain) as opposed to losing it as they age. So, just by walking, the participants reversed the impacts of aging on a major part of their brain.
Now that you know about the 7 different types of memory and how to keep your brain in tip-top shape, begin measuring how your daily choices may actually be affecting your cognitive functions.
If your work requires your neurons to be constantly on their toes in order to prevent accidents (unlike these dangerously sleepy neurons) check out how the AlertMeter measures normal cognitive functioning so you can ensure safety as workers take on critical tasks.
"AlertMeter® is an excellent tool for businesses looking for a real-time impairment testing solution . . . In the age of recreational marijuana, prescription drugs, alcohol use and workplace fatigue, determining an employee's cognitive ability and readiness for work has become complex and often requires more than a drug testing program alone."