Tag Archives: episodic memory

Types of Memory: Learn everything you need to know

Where did you put the keys? Why does she look so familiar? What was his name again? This is a situation we have all been at one point or another. That feeling like we don’t remember where we were going, or what we had on our to-do list for tomorrow. All these situations have in common one cognitive skill: memory. There are different types of memory that can explain why sometimes we are forgetful about certain things and not others. Learn everything about the different types of memory in this article. 

Memory is one of the cognitive abilities that we use daily, without even knowing it. It allows us to properly store new information in our brain so that it can be easily recalled later. Even though this process is intuitive, it’s a lot more complicated than it seems because we have different types of memory. Like other cognitive skills, types of memory can also be assessed. There are many ways of assessing types of memory, from standard testing such as the Weschler’s scales to CogniFit online General Cognitive Assessment.

General Cognitive Assessment Battery from CogniFit: Study brain function and complete a comprehensive online screening. Precisely evaluate a wide range of abilities and detect cognitive well-being (high-moderate-low). Identify strengths and weaknesses in the areas of memory, concentration/attention, executive functions, planning, and coordination.

The good news is that this complex cognitive ability can be trained by practicing specific memory exercises. Even though we’re not always aware of it, we can do things to train our memory to keep it from deteriorating prematurely. It’s much more effective to prevent its decline and boost our memory while its still in shape than to wait until we see signs of memory problems. Memory problems cause anxiety in those who suffer, which is why more and more people are starting routines to help them improve their cognitive functions. Many scientific studies have shown that memory is one of the cognitive abilities that can be trained with exercises designed by neurologists and specialists.

Types of Memory

The main two types of memory are the short-term memory and long-term memory based on the amount of time the memory is stored.

Short-Term Memory: the memory mechanism that allows us to retain a certain amount of information over a short period of time. Short-term memory temporarily retains processed information that either fades quickly or turns into a long-term memory. It is limited and has two objectives. The first is to keep information in our brain without it being present, and the second is to manage this information so that it can be used in higher mental processes. 

Long-term Memory: Long-term memory could be defined as the brain mechanism that makes it possible to code and retain an almost unlimited amount of information over a long period of time. The memories stored in long-term memory can last for up to a few years.

Types of Memory related to short-term memory

Types of Memory: Sensory Memory

We receive sensory memory through our senses and it lasts for a very short period of time, about 200 to 300 milliseconds. This information can be visual, auditory, tactile, smell, etc. These memories either fade or are stored in short-term memory. The information only lasts for as long as it takes to be processed and stored.

Types of Memory: Working Memory

Working memory, or operative memory, can be defined as the set of processes that allow us to store and manipulate temporary information and carry-out complex cognitive tasks like language comprehension, reading, learning, or reasoning. Working memory is a type of short-term memory. Its capacity is limited We are only able to store 5-9 elements at a time. It is active. It doesn’t only store information, it also manipulates and transforms it. Its content is permanently being updated and it is modulated by the dorsolateral frontal cortex.

Once you have assessed the different types of memory, there are different types of activities that help improve them. From games such as Sudoku to full on personalized brain training.

CogniFit Brain Training: Trains and strengthens essential cognitive abilities in an optimal and professional way.

Types of Long-term Memory

Types of Memory: Declarative 

Declarative Memory is the information stored in our memory systems that can be explained and recalled voluntarily and consciously. The brain systems related to this memory system are the medial temporal lobe, the diencephalon, and the neocortex, and is divided into two parts.

Types of Memory: Semantic

Semantic Memory refers to the set of information that we have about the world around us. This information is unrelated to how or when it was learned and includes vocabulary, academic concepts, or anything that we know about a certain subject. For example, you know that an apple is a fruit that you can eat, that there are different colored apples, and that it comes from the apple tree, but you probably don’t remember when you learned this information.

Types of Memory: Episodic

Episodic Memory includes the concrete experiences that we have lived and has a very close relationship to how and when information is learned. For example, remembering what you ate for dinner last night, where you parked your car, when you visited a certain city for the first time, who you went to a certain party with, or when you met that person.

Types of Memory: Non-Declarative or Implicit

Implicit Memory is stored in your memory systems, but can’t be talked about. It is usually acquired or incorporated through implicit learning (you may not be conscious that you’re learning it). This type of memory is quite resistant to brain damage, which usually leaves it less affected than other memory systems. This type of memory uses different parts of the brain, like the neocortex, the amygdala, the cerebellum, and the basal ganglia. It also includes other subdivisions. This is used subconsciously and helps to learn new skills like driving or riding a bike.

Types of Memory: Procedural

Procedural Memory is made up of information of muscular movements that we have learned to automatize through practice, like habits and other skills. For example, riding a bike, throwing a ball, or moving a computer mouse.

Types of Memory: Priming

Priming refers to the ease with which we activate and remember a certain concept in our minds. For example, you would probably remember the word “sedan” quicker if you were talking about “cars”, “trucks” or “convertibles”.

Types of Memory: Classical Conditioning

Classical Conditional relates to the link between a conditioned stimulus and a response that has previously been associated with an unconditioned stimulus. For example, if you hear a bell chiming (conditioned stimulus) before blowing air in your eye (unconditioned stimulus), hearing the bell chime would be enough to cause you to blink (conditioned response). This relationship forms part of the non-declarative or implicit memory

The use of all of these types of memory is essential in our day-to-day, as it is one of the cognitive abilities that we use constantly. 

Semantic Memory: “It’s on the tip of my tongue!”

“It’s on the tip of my tongue!” Semantic memory stores what we now about the world and language. When we want to remember certain things that we’ve learned like the capital of France or the current president of the United States, we’re efficiently using our semantic memory.Find out what semantic memory is, how it works, how it can be improved, and some of the problems related to poor semantic memory.

What is semantic memory? Photo by Tachina Lee on Unsplash

What is semantic memory?

What is semantic memory? Tulving was the first person to establish the term “semantic memory”, which is a type of memory that holds meaning and general knowledge, where our specific experiences don’t come into play.

For example, if you want to answer the question “how many hours are there in a day?”, you don’t have to remember the exact moment in your life that you learned it. Semantic memory allows us to “automatically” remember that there are 24 hours in a day, without having to recall the specific events that led to us learning the information.

We use semantic memory to remember concepts that we’ve learned about the world and language. There is also a type of long-term memory that we acquire that, once it’s learned, we’ll remember it for the rest of our lives.

Semantic memory extends to all of the knowledge that we may learn. For example, if we want to remember that a lion is a mamas that has 4 legs, you don’t need to relate it to any specific event or experience that you’ve had with a lion- it’s just in our brain.

  • Semantic memory is a type of long-term memory: It allows us to remember things for days, years, or decades. There is no limit on its duration.
  • Semantic memory is declarative: This means that we are constantly using it.
  • Difference between episodic and semantic memory: Episodic memory is how we remember autobiographical memories, like what you ate for breakfast, or what you did last weekend. The main difference between these two types of memories is that semantic memory is a type of dictionary that doesn’t require that you have any specific personal knowledge or experience with the word.

Where are words located in the brain? A team of scientists created an interactive map of the areas of the brain that are activated when certain words are heard. This semantic brain map shows how language is distributed through the cortex and both hemispheres of the brain, grouping words by meaning and constructing a brain dictionary.

What does semantic memory do?

Semantic memory gives us a mental dictionary that organizes words, concepts, and symbols that we store throughout our life. It allows us to reserve cognitive resources and interpret, quickly and easily, the world in which we live.

Semantic memory is a fundamental part of our daily life. For example, it allows us to “automatically” know that lions are mammals, without having to go through our brain and think bout the lions that we’ve seen in our life.

Our semantic memory gives a general meaning to the word “lion”: Large mammal with four legs and lots of hair around its head.

If we had to think about all of the lions that exist in the world in order to remember and describe it, it would be impossible. Semantic memory gives us the ability to group multiple concrete concepts (animals, people, objects, etc.) into general concepts. These things can be categorized into an infinite number of areas, like animals, objects, living things, non-living things, mammals, reptiles, etc.).

Alterations of semantic memory: Access disorders and semantic storage

People with semantic dementia: Have problems finding the right meanings for concepts. As with almost any pathology or disorder, symptoms and characteristics of the disorder vary from patient to patient. Semantic dementia is characterized by a difficulty in remembering the meaning of concepts or words, but don’t necessarily have trouble carrying-out the task that the word represents. For example, they may have trouble remembering the word/concept “iron”, but they would be able to use an iron.

People with damage to the prefrontal cortex: It’s been shown that patients with damage to the prefrontal cortex may have trouble carrying-out a task related to a certain word or concept, but don’t have trouble recalling the concept (the inverse of the previous point). People with this kind of brain damage are unable to to certain tasks that may seem simple to others, like going to the dentist when their gums hurt, or washing their clothes when they’re dirty, but are easily able to recall the words for these actions.

Alzheimer’s Disease: Poor episodic (autobiographical) memory is a common characteristic of Alzheimer’s disease, but semantic memory is affected as well. Patients with Alzheimer’s tend to develop language disorders and have a hard time carrying out tasks related to a word or concept.

Exercises to improve semantic memory

1. CogniFit, leader in cognitive assessments and brain games

Being able to easily recall words from our vocabulary is one of our main cognitive skills as humans. Without this, we would constantly be searching for a word in our memory and have that feeling of “it’s on the tip of my tongue!”. It’s common to sometimes forget the exact word that you’re looking for, but if it happens often, it may be a sign of poor semantic memory.

CogniFit is a professional tool that helps assess and improve access to our vocabulary. Studying neuroplasticity has shown that the more we use a neural circuit, the stronger it gets. This idea can be applied to the neural circuits related to naming, working memory, short-term memory, visual memory, auditory short-term memory, contextual memory, etc.

The ability to find the correct word for an object or concept can be improved if it is properly trained. The battery of clinical exercises from CogniFit allows you to assess and train your Naming and other cognitive skills related to memory.

How does CogniFit work? The program first evaluates your cognitive level in certain cognitive skills (like naming), and based on the results gathered, provides a complete brain training program.

The different interactive exercises are presented as fun brain games that can be played on a mobile device or computer. After each session, CogniFit will provide a detailed graph with the user’s cognitive progression.

2. Remember what’s going on around you

Its good to remember what’s going on around you: The best exercises for improving semantic memory are remembering a series of words and increasing the amount and difficulty of the word. For example, try to remember all 50 states in the United States, then the each state’s capitals, and then move on to continents and countries.

3. Learn new languages and travel

Learning new language requires us to expand and learn new vocabulary, new grammar rules, and new sentence structures. Our semantic memory is constantly being used and strengthened as we learn language.

Seeing new places and learning about new cultures can also help you find new ways of doing things. For example, if you might learn that people in a different culture eat, clean, or raise their children differently than you. Exposing yourself to these new ideas can help you adapt to situations when you’re back in your home country.

4. Give meaning to ideas by understand what you’re learning

How does the brain learn? Studies have shown that we learn better and more quickly if we give meaning to the concepts that we learn. For example, when studying for a test, you’ll learn the information much better if you give it some kind of meaning aside from the concept itself. Learn more about memory techniques.

5. Exercises for patients with semantic memory problems

There are a number of different exercises that you can do to help improve semantic memory. You can write down a series of basic questions that the patient has to answer. If they answer incorrectly, correct them in the moment. For example, you could ask the season in the year, the names of the months, or what are the numbers between 1 and 15.

You can also give them incomplete sentences that they have to complete. For example, “lemons are the color…”, “The capital of the USA is…”, etc.

We use our semantic memory everyday, and there is hardly any point of the day where we aren’t using it. It helps us talk, communicate, and learn about the objects and concepts of the world around us. With all of the information that we have stored in our semantic memory, it’s amazing that we’re able to keep it organized and pull up the words that we want at a given time. If you tried to re-learn the days of the week without giving it any meaning, it would be almost impossible. Semantic memory allows us to reserve cognitive resources and store more information in our brain.

Semantic memory allows us to figure out how the world works and carry out the necessary tasks to get through the day (if you’re sick, you go to the doctor), and follow “scripts” almost automatically (go to a restaurant, wait until you’re seated, order food, etc.).

Do you have any questions? Leave me a comment below 🙂

This article was originally written in Spanish by Eva Rodriguez Weisz

Korsakoff Syndrome: inventing memories to compensate forgetfulness

Korsakoff syndrome is a memory problem that is usually due to alcohol abuse or overly restrictive diets that lead to vitamin deficiency. Find out here what it consists of, what are its main symptoms, causes, treatment and how we prevent it.

Korsakoff Syndrome

What is the Korsakoff Syndrome?

Korsakoff syndrome is a chronic memory disorder due to severe deficiency of thiamine, or vitamin B1.

Thiamin helps the brain produce energy from sugar. When levels fall drastically brain cells can’t generate enough energy to function properly and as a result, Korsakoff syndrome can develop.

It is believed that this deficiency causes damage to the thalamus and mammillary bodies of the hypothalamus. Mammillary bodies are brain parts or small structures with many connections to the hippocampus (an area closely related to memory). There is also general brain atrophy, loss, and neuronal damage.

Research has shown that this deficiency alters the substances responsible for transmitting signals between brain cells and storing memories. These alterations can destroy neurons and cause bleeding and microscopic scars throughout the brain tissue.

This syndrome is often, but not always, preceded by an episode of Wernicke’s encephalopathy. This consists of an acute reaction of the brain due to a severe lack of thiamine. Wernicke’s encephalopathy is a medical emergency that causes severe life-threatening brain disturbance, mental confusion, uncoordinated movement and abnormal and involuntary eye movements. Because Korsakoff syndrome is commonly preceded by an episode of Wernicke’s encephalopathy, the chronic disorder is sometimes called Wernicke-Korsakoff syndrome. However, Korsakoff can develop without a previous episode of this encephalopathy.

Korsakoff Syndrome Symptoms

Korsakoff is characterized by memory problems but retaining consciousness. This may give the impression during conversations that he is in full possession of his faculties.

However, he has severe alterations in recent memory. The person will ask the same questions over and over again, read the same page for hours, and is not able to recognize the people they have seen several times in the course of his illness.

Memory problems can be very severe, both short-term memory and long-term memory with many memory gaps or memory loss, while other skills such as social or thoughts may be relatively intact.

The main symptoms are:

  • Anterograde amnesia: inability to form new memories or learn new information.
  • Retrograde amnesia: severe loss of existing memories, prior to the beginning of the disease.
  • Confabulations: invented memories that are believed by the individual himself as real because of memory gaps.
  • Conversation with low content.
  • Lack of introspection.
  • Apathy.

Individuals with Korsakoff syndrome may show different symptoms. In some cases, a patient may continue to “live in the past”, convinced that his life and the world remain unchanged since the beginning of the disorder.

Others may display a wide variety of confabulations. Retrograde amnesia does not happen to all memories alike but affects more in recent events. The older the memories, the more they remain intact. This may be because recent memories are not fully consolidated in our brains, therefore, being more vulnerable to their loss.

Confabulations in Korsakoff Syndrome

One of the most characteristic symptoms of people with Korsakoff syndrome is the confabulations. They often “collude” or invent information they can’t remember. It is not that they are “lying”, but actually believe their invented explanations. There is still no agreed scientific explanation as to why this happens.

Korsakoff Syndrome-Confabulations

Some people may show constant, even frenetic, conspiracies. They continually invent new identities, with detailed and convincing stories that support them, to replace the reality they have forgotten.

Causes of Korsakoff Syndrome

We know that excessive intake of alcohol can harm our nervous system. In fact, in most cases, Korsakoff’s syndrome is due to alcohol abuse and its consequences on our brain.

Research has identified some genetic variations that may increase the risk of this disorder. In addition, poor nutrition can also be an important factor.

Korsakoff syndrome can also be caused by eating disorders, such as anorexia, overly restrictive diets, starvation, or sudden weight loss after surgery. Also by uncontrolled vomiting, HIV virus, chronic infection or cancer that has spread throughout the body.

Treatment of Korsakoff Syndrome

Intervention for Korsakoff syndrome should be approached from a multidisciplinary point of view, in which doctors, psychologists, and neuropsychologists will work to achieve the best results.

Some experts recommend that people who consume large amounts of alcohol or have other risks of thiamine deficiency, take oral supplements, always under the supervision of a doctor.

It is also recommended that anyone who has had a history of alcohol abuse or symptoms associated with Wernicke’s encephalopathy be injected with thiamine. For people who develop Korsakoff Syndrome, treatment with oral thiamine, other vitamins and magnesium may increase the chances of symptoms improving.

A psychological intervention will revolve around maintaining alcohol abstinence. From the neuropsychological point of view, it will help to compensate for their deficits, so that the patient can integrate socially and lead a life as normal as possible. CogniFit is a tool that trains different cognitive skills affected by Korsakoff Syndrome. 

Prognosis of Korsakoff syndrome

Some data suggest that about 25 percent of people with Korsakoff syndrome recover, half improve but don’t fully recover, and another 25 percent remain the same.

According to these researchers, the mortality rate is high, between 10 and 20%. This is mainly due to lung infection, septicemia, liver decompensation disorder and an irreversible thiamine deficiency state.

Early attention and treatment for Korsakoff symptoms is very important. Early treatment of Wernicke’s encephalopathies may improve prognosis and prevent Korsakoff’s syndrome. For example, eye problems begin to improve in hours or days, motor problems, in days or weeks. Although some 60% of patients may have some residual symptoms.

According to these authors, once the Korsakoff syndrome has been established, the prognosis is quite pessimistic. Approximately 80% of patients are left with a chronic memory disorder. These can get to learn simple and repetitive tasks that involve procedural memory (motor memory).

Cognitive recovery is slow and incomplete and reaches its highest level of recovery after one year of treatment. Although recovery may occur, it depends on factors such as age or alcohol withdrawal.

Tips for Preventing Korsakoff Syndrome

Tips for Preventing Korsakoff Syndrome

The primary advice is to reduce your alcohol intake to a minimum. The less alcohol, the better. Although we think that drink very little, the fact is that even in small amounts, we are already damaging our body.

  • A healthy and non-restrictive diet will ensure the synthesis of the vitamins needed to function properly and in particular thiamine or B1.
  • Go to the doctor whenever we detect memory problems. He will establish if it is a problem associated with normal aging or some kind of dementia.
  • Maintain a good support system, since loved ones will be of help in case any disturbing symptoms appear.
  • If you think you drink more than you do and don’t know how to quit, go to a professional who will help you reduce your alcohol intake.

Feel free to leave a comment below.

This article is originally in Spanish written by Andrea García Cerdán, translated by Alejandra Salazar.