Memory Toolkit
Science behind Memory and tools to improve it!
Dear Readers,
This article will discuss the Science Behind Memory and Tools to Improve it! It is important to understand the basics of memory in order to understand learning and change.
Memory: It’s all about Connections
Memory is the process of taking in information from the world around us, processing it, storing it and later recalling that information, sometimes many years later.
When we learn something—even as simple as someone’s name—we form connections between neurons in the brain. The connections which are formed between neurons is called a synapse. These synapses create new circuits between nerve cells, essentially remapping the brain. Synapses get stronger or weaker depending on how often you are exposed to the event.
Neurons or nerve cells are the fundamental units of the brain and nervous system. They are information messengers. They use electrical impulses and chemical signals to transmit information between different areas of the brain, and between the brain and the rest of the nervous system. Within a neuron, the impulse moves to the tip of an axon and causes the release of neurotransmitters, chemicals that act as messengers.
There are about 85 billion neurons in a typical adult human brain, and about ten quadrillion connections - or synapses - between all those neurons (that’s a ‘1’ followed by 16 zeros!). And that is just the neurons. There are another 86 billion non-neuronal cells (microglia, oligodendrites, astrocytes, ependymal cells) that also contribute to information processing by cross-talking with those 85 billion neurons.
Information Processing Model of Memory
Information comes in through our senses—our ears, eyes, skin, nose, or taste buds. This information gets encoded only if you are paying attention.
Attentive information gets routed either through the low road —the amygdala (our emergency fight-flight/emotional memory storage center), or the high road—the hippocampus-cortex (our memory storage center.)
And once information comes in, it needs to get encoded—and by that I mean, it needs to be ‘written’ in a language the brain understands so it can be stored and remembered. That means neuronal connections or synapses.
Lastly, we call back our stored information. We have to locate the information in our brain and return it to our consciousness.
Types of Memory
Sensory memory allows individuals to retain impressions of sensory information after the original stimulus has ceased. One of the most common examples of sensory memory is fast-moving lights in darkness: Sensory memory is not involved in higher cognitive functions like short- and long-term memory; it is not consciously controlled. The role of sensory memory is to provide a detailed representation of our entire sensory experience.
Short-term memory is also known as working memory. It holds only a few items (research shows a range of 7 +/- 2 items) and only lasts for about 20 seconds. However, items can be moved from short-term memory to long-term memory via processes like rehearsal.
Long-term memories are all the memories we hold for periods of time longer than a few seconds; long-term memory encompasses everything from what we learned in first grade to our old addresses to what we wore to work yesterday. Long-term memory has an incredibly vast storage capacity.
There are many types of long-term memory.
Explicit or declarative memory requires conscious recall; it consists of information that is consciously stored or retrieved. Explicit memory can be further subdivided into semantic memory and episodic memory.
Procedural/implicit memories are not based on consciously storing and retrieving information, but on implicit learning. Often this type of memory is employed in learning new motor skills. An example of implicit learning is learning to ride a bike: you do not need to consciously remember how to ride a bike, you simply do. This is because of implicit memory.
Where are Memories Stored ?
In our Brain we have different regions to store different types of memory. Short-term memories are processed in the prefrontal cortex, which is also responsible for other complex cognitive functions, such as decision making. Explicit long-term memories are stored in the hippocampus, neocortex, and amygdala. The hippocampus stores episodic memories, the neocortex stores semantic memories, and the amygdala connects memories to emotions. Memories connected to strong emotions like love and fear are harder to forget, as they are strengthened by the neural connections to the amygdala. This is why post-traumatic stress disorder (PTSD) is so serious and difficult to treat.
Implicit long-term memories are stored in the basal ganglia and the cerebellum. The basal ganglia is especially involved with movement and sequences of motor activity (e.g., learning to ride a bike). The cerebellum stores memory of fine motor skills, such as holding a pencil or typing on a keyboard.
If you are interested to learn more about the Science of Trauma please check the CMC's Youtube channel or join us on Feb 24 for Science Book Meetup where we will be discussing Gabor Mate's book on Trauma!
Learning Strategies to Improve Memory
Now let's shift gears and discuss different learning strategies to improve memory!
Here I will share 3 crucial learning strategies: which will definitely help you to move information faster from short-term memory to long term memory. These memory strategies are : urgency, repetition, or association.
1. Urgency
Urgency, with the release of stress hormones, creates a powerful wash of chemicals that strengthens the connection between neurons or synapses. And, urgency also determines how and where the brain encodes the information into long term memory. Urgency can create a very long lasting memory—after a single exposure to a threat, the amygdala can retain that memory for an entire lifespan. However, the encoding or labelling of the event—the ability to recall or retrieve the memory can be more troublesome, and not under conscious control—so that the information gets stored with an emotional, rather than a narrative marker. For example, I can pass by where I had my car accident and get anxious, even if I don’t have a conscious memory of the event. This is how Traumatic memories gets stored and retrieve unconsciously in presence of familiar cue.
The other form of urgency, is when faced with mild stressful situations, such as Exams, tight deadlines and interpersonal conflicts. While stress around the time of learning is thought to enhance memory formation, thus leading to robust memories, stress markedly impairs memory retrieval. Also, stress may hamper the updating of memories in the light of new information and induce a shift from a flexible, ‘cognitive’ form of learning towards rather rigid, ‘habit’-like behaviour.
Together, these stress-induced changes may explain some of the difficulties of learning and remembering under stress in the classroom, business meeting, etc.
2. Repetition
Repetition is an essential learning aid. It allows a conscious skill to transfer into one's subconscious, freeing up working memory and allowing for further skills learning.
The other way of learning is cramming - which we think will work but it doesn't! Cramming is essentially trying to stuff a load of information into your short-term memory in time for an upcoming exam. However, this may will most likely mean that you’ll have no lasting connections to the knowledge, and you won’t develop any deep understanding of the information. You’ll also likely forget it the second you walk out of the exam.
The memories in your brain become stronger through repeated, spaced study sessions, which is what ‘spaced repetition’ is all about.
Before going to spaced repetition let’s look at the Ebbinghaus Forgetting Curve:
It is a graph that represents the way information is forgotten over time. This forgetting curve starts with near-perfect recall in the beginning, but as a person continues to forget the material, the curve flattens until the bottom line, where the person can’t remember anything at all about what was studied.
What’s important here, though, is that our memory becomes stronger when we revisit information after forgetting some of it: a concept called the “Theory of Disuse”. This means that not only do we avoid losing the information by using spaced repetition, but we also strengthen these memories by letting ourselves partially forget the information and then strengthening it again using recall.
In Brain talk - “Neurons that fire together, wire together!” Neuropsychologist Donald Hebb first used this phrase in 1949 to describe how pathways in the brain are formed and reinforced through repetition.
Spaced Repetition: Remembering What You Learn
Repeatedly encountering material at a spaced interval is more effective than reviewing the material multiple times in the same study session.
Spaced repetition reduces the forgetting that occurs when material is not encountered for a significant time period.
Spaced repetition involves actively recalling learned material, which supports learning. Also, if an item is forgotten, you are prompted to use a more effective learning strategy to retain the information for later reviews.
3. Association: Mnemonic Strategy
Association and learning can be well explained from Pavlov’s classic experiments, where he found that dogs could learn to salivate at the sound of a bell.
There are different association learning techniques referred to as Mnemonic. A mnemonic is a memory technique or a memory tool that serves as a bridge to help you recall information from long-term memory. We knew back in 1967 from a study by Gerald R. Miller that mnemonics increased recall. He found that students who regularly used mnemonic devices increased test scores up to 77%!
The 9 basic types of Mnemonics :
1. Music Mnemonics: work best with long lists. You can make a song or jingle using any type of music you choose for any list of items. Ex the “ABC” song
2. Name Mnemonic: the 1st letter of each word in a list of items is used to make a name of a person or thing. Ex VIBGYOR
3. Name of Expression Mnemonics: To make an Expression or Word mnemonic, the first letter of each item in a list is arranged to form a phrase or word. Ex My Very Educated Mother Just Served Us Nachos (Planets Name)
4. Model Mnemonics: some type of representation is constructed to help with understanding and recalling important information.
5. Ode or Rhyme Mnemonics: puts information to be recalled in the form of a poem.
6. Note Organization Mnemonics: Notecards, Outlines, Cornell System
7. Image Mnemonics: is constructed in the form of a picture that promotes recall of information when you need it. The sillier the Image Mnemonic is, the easier it is to recall the related information. These images may be mental or sketched into text and lecture notes.
8. Connections Mnemonics: the information to be remembered is connected to something already known.
9. Spelling Mnemonics: A principal at a school is your pal, and a principle you believe or follow is a rule.
Long Term Synaptic Plasticity
The stimulation from urgency, repetition or association will actually create new proteins inside your neuron - at the level of the synapse a self-perpetuating protein is created which keeps the connection going between neurons. This is a long lasting self-perpetuating protein, and it gets strengthened with repetition. In addition to this self-perpetuating cycle, the neuron, through the protein process also creates a new synaptic terminal growth—to increase the connection—it adds another branch on its tree to strengthen and increase the network. So repetition actually grows the brain’s neural network.
Normal and Not Normal Memory Decline
Normal Memory Lapses
Six types of normal memory lapses for American Association of Retired Persons that are not a cause for worry:
Absentmindedness: happens when “original awareness” is missing. Observation is essential for original awareness, and it’s not the same as just “seeing”. There is difference between what eyes "see” and what the mind “observes”.
Blocking: usually occurs from several memories creating a disruption.
Scrambling: when confusing the little details. A glitch in the hippocampus is likely to blame for this. It has incorrectly recorded the time and place of the facts.
Fading away: Memories that are not recalled often can begin to fade away because those memories care not being reinforced. This basic use-it-or-lose-it characteristic of memory is called transience, and it’s normal at all ages.
Struggling for retrieval: aging changes the strengths of the connection between neurons in the brain, and new information can delete other items from short-tem memory unless it is repeated again and again.
Muddled Multitasking: as we age it takes more effort to maintain focus and is interrupted it takes longer to get back to original task.
NOT Normal
Signs that it might be time to talk to a doctor include:
With early dementia, one of the first things that people notice is difficulty retrieving the details of events
Asking the same questions over and over again
Getting lost in places a person knows well
Having trouble following recipes or directions
Becoming more confused about time, people, and places
Not taking care of oneself —eating poorly, not bathing, or behaving unsafely
Brain Fog
Brain Fog is characterized by confusion, forgetfulness, and a lack of focus and mental clarity. This can be caused by overworking, lack of sleep, stress, and spending too much time on the computer. The other medical reasons can be Inflammatory conditions like Multiple Sclerosis, Autoimmune disorders like Lupus, Asthma and allergies, Anxiety, depression and stress, Cancer treatments, Hormonal changes, Chronic Fatigue Syndrome, certain medications, Sleep.
Long COVID
Brain fog or cognitive dysfunction is one of the common post COVID symptoms. While for most people these symptoms do not last for long, some may experience memory issues for months. Covid can lead to vascular damage due to low oxygen electrical dysfunction and neurotransmitter imbalance. So we must look to protect the brain from covid induced memory loss.
Pregnancy and Menopause
Dipping levels of estrogen from either menopause or pregnancy can affect brain function and cause these momentary lapses in recollection. Midlife “brain fog” is treatable. Hormone therapy has been shown to sharpen a menopausal mind and may help protect you from further memory loss.
Types of Cognitive Deficits
Normal Aging
Mild Cognitive Impairment
Dementia: Vascular Dementia, Dementia with Lewy Bodies, Frontotemporal Lobar Dementia, Alzheimer’s Disease
Brain begins to age in one’s mid-twenties and can structurally begin to deteriorate as early as age 30. After age 40, the hippocampus shrinks by about 0.5% per year. The shrinkage is quite variable among individuals and heavily depends on individual’s lifestyle choices, environment factors and genetic predisposition.
However, there is some exciting news!! Studies have also shown that hippocampus, brain’s memory center retains the ability to make new neurons from precursor cells in healthy older folks. In other words, aging does not mean there will be inevitable cognitive decline.
I will discuss in detail all about Neurodegenerative disorders in April Meetup! All are welcome to attend the live webinar, click on the link to be a member of “Curious Minds Community”.
Memory ToolKit
Now the final section of today’s talk - the memory tool kit – simple lifestyle modifications which can be easily incorporated to improve the memory function of brain.
It includes 5 things – Move, discover, relax, nourish, connect!
1. The Miracle of Movement
Physical activity has the strongest evidence to date of positive brain changes
We don’t get that much slower with age until we reach 70.
Low intensity activities like walking, gardening, or ballroom dancing can be beneficial more than we previously realized. Regular physical exercise at least 150 mins a week. Mix it up with interval and strength training
Interval Training means you alternate between varying levels of speed, intensity, and effort. Think of it as surprising the body so you don’t fall into the well-worn ruts that fail to challenge the body and lead to plateau in your process. Strength training refers to use of weights or just your own weight as resistance. This helps build muscle mass and tone and helps balance and coordination.
How Exercise boosts your Brain health ?
It decreases feelings of anxiety: Studies have shown every time your move your body, a number of beneficial neurotransmitters, including dopamine, norepinephrine, serotonin and acetylcholine, gets released into your brain.
Improves focus and concentration
Promotes the growth of new brain cells
Protects the brain from aging and neurodegenerative diseases
Exercising Your Brain
Exercising brain is another way to stay mentally fit. If your regular daily activity or work is primarily left-brained (your brain’s left side is the thinking or logical side) then switch to doing right-brained activities (the right side of your brain is your creative center tied to the creation of music, art and imagination) — and vice versa.
2. The Power of Purpose, Learning and Discovery
ACTIVE AGING! Building BRAIN RESILIENCY OR COGNITIVE RESERVE
Find activities that are joyful and stimulating. Stay engaged. There’s power to maintaining a sense of purpose by continuing to learn, discover, and complete complex tasks. The complexity of the new skill is critical; you can’t just come to class and be passive. You need to use your mind in a manner that gets you out of your comfort zone and demands more long-term memory.
Two Forms of Cognitive Reserve:
Neural Reserve: Preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption.
Neural Compensation: Alternate networks may offset or balance out any disruption of preexisting networks.
Cognitive reserve is a reflection of how much you have challenged your brain over the years through your education, work, and other activities. Cognitive stimulation increases the density of neurons, synapses and dendrites and hence builds a brain more resistance to disease.
3. The Need for Sleep and Relaxation
Sleep Is The Rx For Brain Health
Sleep affects almost every type of tissue and system in the body – from the brain, heart, and lungs to metabolism, immune function, mood, and disease resistance.
According to neuroscientists, sleep is restorative, whereas sleep deprivation lowers your resistance to stress and harms your brain. Lack of sleep interferes with memory and learning. Your brain moves slower. You're more forgetful, and your attention is short-circuited. Bad sleep prevents the brain from cleansing itself of debris (Glymphatic system), leading to extra amyloid hanging around.
I will elaborate on The Science of Sleep in next article. Stay tuned! Subscribe to this newsletter and share it with your friends and family.
4. Food for Thought
Avoiding an entire food group or restricting certain foods is not an ideal approach
Focus more on what you should eat instead of what you shouldn’t eat
Say good bye to strict dietary protocols that are unrealistic and challenge your will power.
Guilt is bad for your brain and too much of it makes you lose your sharpness.
MIND Diet: Mediterranean and DASH (Dietary approaches to stop hypertension) Intervention for Neurodegenerative Delay
No single food acts as a silver bullet for improving or maintaining brain health. It’s the combination of foods and nutrients in our meals
Check your thyroid and vitamin B12 levels and normalize them.
Follow the S.H.A.R.P. Way!
S: Slash the Sugar and Stick to your ABCs
A-List Foods to Consume Daily (Fresh vegetables, whole berries, fish and seafood, healthy fats, nuts and seeds)
B-List foods to Include (Beans and other legumes, whole fruits, low sugar, low fat dairy, poultry, whole grains)
C-List Foods to Limit (Fried food, pastries, sugary foods, processed foods, red meat, whole fat dairy high in saturated fat, salt)
H: Hydrate Smartly
A: Add More Omega-3 fatty Acids from Dietary Sources
R: Reduce Portions
P: Plan Ahead
5. Connection for Protection
Recent studies show that loneliness and social isolation plays an important role in maintain brain health and help in memory function of brain
Having access to others for emotional support or listening to you seems to have a protective brain health effect — increased levels of brain-derived neurotrophic factor, and reduced risks for dementia or stroke,"
Social isolation was associated with about a 50% increased risk of dementia.
What makes a Good Life ? Robert Waldinger’s explains-
Having social connections is better for our health and well being—and conversely, loneliness kills.
Having higher-quality close connections is more important for our well-being than the number of connections.
Having good relationships is not only good for our bodies but also for our brains.
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