Tag Archives: short term memory

Short term memory: What is it and practical exercises

What is short-term memory? How is it different from long-term memory? In the following article, we will try to answer these and other questions with practical examples and everyday situations.

Short term memory

What is short term memory?

Short term memory is a system that allows us to store a limited amount of information for a short period of time.

For example, short-term memory has made it possible for you to be able to read the previous sentence and understand its meaning. Without short term memory, by the time you had reached the last word of the sentence, you would probably have forgotten the first word you read. We use short-term memory many times in our daily lives. Another example would be when someone gives us their phone number: we need short-term memory to keep the number in our mind for as long as it takes us to write it down or dial it on our phone.

Activities to exercise short-term memory

How much information can we store thanks to short-term memory? And for how long? To answer these questions, we are going to use the following exercise:

1. Remembering numbers

Read aloud the following numbers: 7293 and then cover them with a piece of paper. Can you remember the numbers in the same order? Well, let’s try more numbers. Cover them with a piece of paper as soon as you have read them and try to remember each set of numbers in the same order in which they are written before moving on to the next set. Ready?

  • 40863
  • 785342
  • 7916382
  • 16249067
  • 912308462
  • 6129347320

How many numbers have you been able to remember? This type of task is known as a digit span. It has been used on numerous occasions to study short-term memory. In this task, most people remember about seven digits in the same order.

Therefore, what this task tell us about short-term memory is that a person has a short-term memory capacity of about seven elements. As for the duration of this type of memory, as you have seen, the elements remain in our mind only for a few seconds and then they vanish.

In summary, short-term memory is a fragile type of memory with a limited capacity, very sensitive to interference. The content stored in short-term memory usually disappears within a few seconds unless we repeat it over and over again or use some other strategy. In these cases, the stored information may become part of the long-term memory. Unlike short-term memory, long-term memory is stable, insensitive to interference, and long-lasting.

2. Free recall task

Another way to study short-term memory is through the free recall task. This task consists of repeating a long list of words a certain number of times in order to see the learning process of the person evaluated. Let’s look at an example of this type of task. Next, words will appear in four columns. Read them consecutively, cover them with a piece of paper and try to remember the words you have read. You don’t have to remember the words in the same order they appear.

short term memory list

What words do you remember? Write them down on a piece of paper and repeat the procedure four more times. Have you managed to remember all the words?

When doing this task, it often happens that especially in the first attempts, the people evaluated prefer to remember the first and last words on the list. Remembering the first words on the list is known as the primacy effect and occurs in a stable way throughout repetitions. In this case, “analysis, approach, and area” would be more likely to be remembered than words in the middle columns. On the other hand, remembering the last words in the list is called the recency effect and has particular characteristics. At the end of the list, we are more likely to remember the words “structure, theory, and variable” than the words in the middle columns. Unlike the primacy effect, the recency effect is very sensitive to interference. This means that if we take a break after reading the list or do another task before trying to remember the words in the list, the recency effect will fade away and we will no longer remember which were the last words we had read.

The primacy effect is related to long-term memory or learning, while the recency effect depends on how we use short-term memory.

A trick to train your short-term memory: Chunking

Several studies show that training can improve a person’s performance o short-term memory tasks. One strategy to increase the number of elements we are able to repeat in a digit span task is chunking. A chunk can be defined as a set of elements treated as a unit. For example, the first sequence of digits we saw in the first section was 7293, which is equal to four elements, 7, 2, 9 and 3. However, if instead of reading digit by digit we read that sequence as “7.293”, we will be coding those four digits as a single element, a chunk.

Let’s see another example of chunking, but this time using letters instead of digits. Let’s imagine that we have to memorize a sequence of ten letters: “h”, “a”, “p”, “p”, “i”, “n”, “e”, “s”, “s”. To repeat this sequence of letters, we need to retain ten elements in our short-term memory system. Instead, we can put those ten letters together in the word “happiness” which will count as a single element.

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Studies have shown that the retention capacity of chunks in digit-width tasks is about four or five chunks.

A well-known example of this type of memory training using the chunking technique is the S.F. case, presented by researchers Ericsson, Chase and in 1980. S.F. was a normal person with average intellectual performance who, after more than a year’s training in digit tasks, went from repeating seven digits to repeating 79. How could S.F. achieve this? The researchers stated that S.F. grouped the digits presented in chunks of three and four digits each, and then associated each chunk with mnemonic strategies of time it took runners to complete a race. Thus, the sequence “3, 4, 9, 2” was categorized as “3 minutes and 49.2 seconds”, a world record in one race. In other words, S.F. associated each of the sets of digits retained in his short-term memory with codes that already existed in his long-term memory.

However, the fact that S.F. could repeat up to 79 digits in the digit range task does not mean that he had short-term since as we said in the first section, short-term memory is a system with limited capacity. In fact, when the researchers changed the format of the task and S.F. had to repeat sequences of letters instead of digits, the number of letters he was able to repeat was no longer 79, but about seven elements or four/five chunks.

Curiosities: Clive Wearing

Another highly studied case in psychology in relation to memory is the case of Clive Wearing, a case that has linked memory with consciousness. Clive Wearing was a musician who suffered acquired brain damage as a result of an infection by herpes. The brain damage from this infection caused Wearing to have an important effect on his memory.

In addition to losing most of his memories, Clive Wearing lost his ability to retain information beyond a few seconds or minutes. That is, the information remains in his memory only for a few seconds and then fades away without becoming part of his long-term memory. As a result, Wearing is unable to recognize the people he works with every day or remember what has happened to him.

What Wearing seems to experience is that he recovers his consciousness, as reflected in a diary that he updated every few minutes. During those seconds or minutes, Clive Wearing felt he had woken up and didn’t remember anything he had done minutes before. When his temporary memory store was exhausted, all the information retained during those seconds would fade away and Clive would rewrite that he had regained consciousness.

However, some memories from Clive’s previous life remained, such as his musical ability. This can be seen as evidence that memory is a complex system that includes different independent memory systems.

References

  • Baddeley, A. D. (2014). Essentials of human memory. New York, United States: Psychology Press.
  • Baddeley, A. D., Thomson, N. Buchanan, M. (1975). Word and the structure of short-term memory. Journal of verbal learning and verbal behavior, 14, 575-589.
  • Schwarb, H., Nail, J. and Schumacher, E. H. (2015). Working memory training improves visual short-term memory capacity. Psychological Research, 80(1): 128-148.
  • Ericsson, K. A., Chase, W., and Faloon, S. (1980). Acquisition of a memory skill. Science, 208, 1181-1182.
  • Morgado, I. (2005). Psychobiology of learning and memory. Cuadernos de Información y Comunicación, 10, 221-233.
  • Mathy, F. and Feldman, J. (2012). What’s magic about magic numbers? Chunking and data compression in short term memory. Cognition, 122, 346-362.

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.

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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. 

Development of Cognitive Skills; Piaget’s theory.

Crawl before you walk, walk before you run! When it comes to development, this phrase is certainly true. Before children learn to talk and are taught to problem solve at school, right from birth, they begin to develop novel ways of communicating and exploring the world around them. They cry to tell you they’re hungry, and go through a stage where it seems they’re trying to eat everything (I’m sure the parents reading this can relate)! These practices enable babies to make sense of the world. As they get older, their way of exploring rapidly evolves. As well as developing the ability to walk and talk, our development of cognitive skills (memory, attention, language, reading comprehension, fine motor and gross motor skills) are developed throughout our childhood.

French Psychologist Jean Piaget, proposed the development of cognitive skills during childhood occurs in 4 distinct stages. Each stage builds upon the previous one. Piaget’s theory was ground breaking at the time, as it was previously thought that children didn’t develop cognitive skills until they began to acquire language. Piaget challenged this, as he found that children explore the world around them before they acquire language by using their different senses. This is known as the sensorimotor stage, which is one of four stages that classify a child’s learning stages. The other three stages are known as the pre-operational stage, concrete operational stage and the formal operational stage. During each stage, children acquire new cognitive skills, whilst developing skills they have acquired in previous stages.

Cognitive development

Development of Cognitive Skills: Sensorimotor stage

This stage lasts from birth to 2 years.

In this stage, children learn about the world using their senses and manipulating objects. Here a child’s intelligence is based on their motor and sensory knowledge. During this stage, children learn of object permanence, i.e. although a toy is out of sight, it still exists. This information is extremely important as it prepares children to be able to name objects.

3 months– Infants are able to recognise faces and imitate facial expressions (above).

6 months– Infants can imitate sounds, recognise their parents and display fear towards strangers. They understand the difference between animate and inanimate objects. Between four and seven months, children begin to recognise their own name.

9 months– Infants imitate gestures and actions. The understand simple words like ‘no’ and begin to test their parents’ response to their behaviour.

12 months– Infants can follow moving objects. They can speak between two to four simple words like ‘mama’ and ‘dada’. They can imitate animal sounds and begin to display attachments to objects such as a toy or blanket. At this age, they will also begin to display separation anxiety.

18 months– Vocabulary increases to around 50 words. Children begin to identify body parts and display sense of ownership. They can follow simple instructions (e.g. picking up toys and putting them in the box). They begin to show an understanding of discipline and have knowledge of appropriate and inappropriate behaviour.

Development of Cognitive Skills: Pre-operational stage

This stage lasts from 2 – 7 years.

A child’s vocabulary is around 150 words. Around this time, children learn around 10 new words a day, and begin to understand emotions such as love, trust and fear. Children also begin to learn through pretend play, or “make believe”. However, their view of others and logic isn’t well understood, and children have a self-centered view of the world. In this stage, children begin to use their imaginary and memory skills, and begin to develop their social interaction skills and play cooperatively with children their own age. They will begin to develop their cognitive abilities. Children learn to read, develop routines and display an increased attention span. At the beginning of this stage, children develop their attention, long term and short term memory. As children get older, they learn to control their attention and use their cognitive abilities to help them solve problems and achieve their goals. Also during this stage of development, auditory processing is further refined. This is highly important in improving reading skills.

Imaginative play

Development of Cognitive Skills: Concrete operational stage

This stage is from 7-11 years.

During this stage, children learn to be less egocentric and self centered. They begin to think about the thoughts and feelings of others, and they are more aware of their own thoughts and feelings and the rules around sharing them with others. Children are also able to think in a more logic manner and see the world from the view of others. However, at this stage, a child’s thought is often rigid, therefore they tend to struggle with abstract concepts. Here children learn that things, such as volume and weight, can stay the same despite changes in the appearance of objects. For example, two different glasses can hold the same volume of water. Also, at this stage, children’s attention span begins to increase with age. At the age of six, the child may be able to focus on a task for around 15 minutes. At the age of nine, children can focus on a task for around an hour.

Concrete operational stage

Development of Cognitive Skills: Formal operational stage

This stage is from 11 years and upwards.

Children are able to better understand logic and abstract ideas. They will start to reason and think about abstract ideas, and implement these ideas into their lives. They are also able to see multiple solutions to problems, and begin to look at the world in a scientific manner. During this stage, Adolescents display independent problem-solving skills, and are able to understand abstract ideas such puns, proverbs, metaphors, analogies, philosophy and maths. Children also learn to apply general information to specific situations. During adolescence we undergo cognitive transition, which means that the way we think becomes more advanced, more efficient, and more complex. Thought is no longer limited to what is real, it is expanded to include the hypothetical. During this stage we begin thinking about the process of thinking, known as metacognition. Thought becomes multidimensional; we are able to look at multiple outcomes to a specific problem, which allows us to think rationally and analyze the problem. This will hopefully help us to make well-informed decisions.

Every child will progress through each stage in order, but it’s important to remember that each child is different, so that manner or time that it take a child to develop these skills may vary- and that’s OK! Progression through the 4 stages of development can occur at different rates; some faster than others. We all have a unique cognitive profile, some cognitive skills can be weaker than others. A cognitive assessment can help us to identify which of our cognitive skills are weaker. This enables us to tailor our cognitive training, and improve our weaker skills. If you are looking to strengthen your cognitive skills, why not try some brain games! If you are concerned that about your cognitive abilities or the development of a child, it is important to seek professional advice.

If you have any questions, comments or suggestions, get in touch below! 🙂

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.

Hippocampus: the orchestra director in the deepest part of our brain

Hippocampus. Have you ever gone blank and forgotten what you were going to say? Our brain is full of important data and information that we have stored over the years. Sometimes we have so much information that we force our brain to get rid and ignore some data. The part of the brain in charge of such important functions as memory and learning is the hippocampus. Without this brain structure, we would lose the ability to remember and feel the emotions associated with memories. You want to know more? Keep reading!

Hippocampus

What is the Hippocampus?

The hippocampus is named after the anatomist Giulio Cesare Aranzio who in the 16th century observed that this brain structure bears a great resemblance to a seahorse.

The word hippocampus comes from the Greek Hippos (horse) and Kampe (crooked). In his discovery, this part of the brain was related to the sense of smell and he advocated the explanation that the hippocampus’ main function was to process the olfactory stimuli.

This explanation was defended until in 1890 when Vladimir Béjterev demonstrated the actual function of the hippocampus in relation to memory and cognitive processes. It is one of the most important parts of the human brain because it is closely related to memory functioning and emotions. It is a small organ located within the temporal lobe (approximately behind each temple), which communicates with different areas of the cerebral cortex in what is known as the “hippocampus system.” It is a small organ with an elongated and curved shape. Inside our brain, we have two hippocampi, one in each hemisphere (left and right).

The hippocampus is known as the main structure in memory processing.

Where is the Hippocampus?

It is very well located, connected to different regions of the brain. It is located in the middle temporal lobe.

The hippocampus along with other brain structures such as the amygdala and hypothalamus form the limbic system and are responsible for managing the most primitive physiological responses. They belong to the most “ancient, deep and primitive” part of the brain, in a part of the brain known as “archicortex” (the oldest region of the human brain) that appeared millions of years ago in our ancestors to meet their most basic needs.

The blue part is the hippocampus

What does the Hippocampus do?

Among its main functions are the mental processes related to memory consolidation and the learning process. As well as, processes associated with the regulation and production of emotional states and spatial perception. How does the brain learn?

Some research has also linked it to behavioral inhibition, but this information is still in the research phase as it is fairly recent.

Hippocampus and Memory

The hippocampus is primarily related to emotional memory and declarative memory. It allows us to identify faces, to describe different things and to associate the positive or negative feelings that we feel with the memories of the lived events.

It intervenes in forming both episodic and autobiographical memories from the experiences we are living. The brain needs to “make room” to be able to store all the information over the years and for this, it transfers the temporal memories to other areas of the brain where memory storage takes place in the long term.

In this way, older memories take longer to disappear. If the hippocampus were damaged, we would lose the ability to learn and the ability to retain information in memory. In addition to allowing the information to pass into long-term memory, it links the contents of the memory with positive or negative emotions that correspond depending on whether the memories are associated with good or bad experiences.

There are many types of memory: semantic memory, visual memory, working memory, implicit memory, etc. In the case of the hippocampus, it intervenes specifically in declarative memory (it covers our personal experiences and the knowledge we have about the world), managing the contents that can be expressed verbally. The different types of memory are not governed solely by the hippocampus but are formed by other brain regions. It does not take care of all the processes related to memory loss but it covers a good part of them.

Hippocampus and Learning

It allows learning and retention of information since it is one of the few areas of the brain that have neurogenesis throughout life.

That is, it has the ability to generate new neurons and new connections between neurons throughout the life cycle. Learning is acquired gradually after many efforts and this is directly related to it. For new information to be consolidated in our brains, it is vitally important that new connections are formed between neurons. That is why the hippocampus has a fundamental role in learning.

Curiosity: Is it true that the hippocampus of London taxi drivers is bigger or more developed? Why? London taxi drivers must pass a hard memory test where they must memorize a myriad of streets and places to get the license. In the year 2000, Maguire studied London taxi drivers and observed that the posterior hippocampus was greater. He also noted that the size was directly proportional to the time the taxi drivers were working. This is because of the effect of training, learning and experience changes and shapes the brain.

Spatial perception and its relationship with the hippocampus

Another important function in which the hippocampus stands out is the spatial orientation, where it plays a very important role.

Spatial perception helps us to keep our mind and body in a three-dimensional space. It allows us to move and helps us interact with the world around us.

There have been different studies with mice where it is stated that it is an area of vital importance for orientation capacity and spatial memory.

Thanks to its correct functioning, we are capable of performing acts such as guiding us through cities we do not know, etc. However, the data concerning people are much more limited and more research is needed.

What happens when the hippocampus is disturbed?

An injury to the hippocampus can mean problems generating new memories. An brain injury can cause anterograde amnesia, affecting specific memories but leaving intact learning skills or abilities.

Lesions can cause anterograde or retrograde amnesia. Non-declarative memory would remain intact and uninjured. For example, a person with a hippocampal injury may learn to ride a bicycle after the injury, but he would not remember ever seeing a bicycle. That is, a person with the damaged hippocampus can continue to learn skills but not remember the process.

Anterograde amnesia is memory loss that affects events occurring after the injury. Retrograde amnesia, on the other hand, affects the forgetfulness generated before the injury.

At this point, you will wonder why the hippocampus is damaged when there are cases of amnesia. It is simple, this part of the brain acts as a gateway to brain patterns that sporadically retain events until they pass to the frontal lobe. One could say that the hippocampus is key to memory consolidation, transforming short-term memory into long-term memory. If this access door is damaged and you can’t save the information, it won’t be possible to produce longer-term memories. In addition to losing the ability to remember, when injuries or damage to the hippocampus occurs, you may lose the ability to feel the emotions associated with such memories, since you would not be able to relate the memories to the emotions that evoke it.

Why can the Hippocampus be damaged?

Most of the alterations that may occur in the hippocampus are produced as a result of aging and neurodegenerative diseases, stress, stroke, epilepsy, aneurysms, encephalitis, schizophrenia.

Aging and dementias

In aging in general and dementias such as Alzheimer’s disease in particular, the hippocampus is one of the areas that has previously been damaged, impairing the ability to form new memories or the ability to recall more or less recent autobiographical information. Memory problems, in this case, are associated with the death of hippocampal neurons.

Most of us know of someone who has suffered or suffers from some kind of dementia and has experienced memory loss. It is curious how the memories that remain are childhood memories or the oldest memories. You may wonder why this happens if the hippocampus is supposed to be damaged.

Well, although it is severely damaged (whether by dementia or any other type of illness), the most common memories are the oldest and they are also the most relevant to the life of the person. This is because over time these memories have been “becoming independent” of the hippocampus to be part of other structures related to long-term memory.

Hippocampus and stress

This region of the brain is very vulnerable to periods of stress because it inhibits and atrophies the neurons of this structure.

Have you noticed that when we are very stressed and we have a billion things to do sometimes we feel forgetful?

Stress and specifically cortisol (a type of hormone that is released in response to stressful moments) damage our brain structures sometimes causing neuronal death. That is why it is fundamental that we learn to remain calm and manage our emotions to get our hippocampus to remain strong and continue to exercise their functions optimally.

To know more watch the following video.

If you like this super interesting subject about memory, I recommend you watch the movie “Memento”. I’ll leave the trailer here so you can see what it’s about.

If you liked this post, leave your comment below. I will be happy to read it and answer your questions :).

This article is originally in Spanish written by Mairena Vázquez, translated by Alejandra Salazar.

Motor Memory: Why You Never Forget How to Ride a Bike

Motor memory is the result of motor learning, which involves developing new muscular coordination. This allows us to recall motor coordination we have learned in order for us to interact with the environment. Playing the piano, catching a ball, and riding a bike are all examples of motor memory. These activities are also examples of things that are rather hard to forget how to do. How is this true? What makes our muscles able to remember so well?

Motor memory- Like riding a bike

Motor Memory: Types of Memory

Motor memory, like any form of memory, has a short and a long-term component. Short-term motor memory is very similar to that of verbal short-term memory in general concept but different in where it is stored in the brain and other aspects.

Short-term memory only encompasses the temporary stage of memory storage. In order to store memories for longer periods of time, repetition of the task must be done to move the memory from short-term to long-term memory. In long-term memory, especially when looking at the typical or “non-motor” memory, the information stored does not include specifics as time goes on. The information is rather stored with the big ideas of the memory and small details ultimately fall away.

Motor Memory: The Muscles (almost) Never Forget

The examples given earlier of playing piano, catching a ball, and riding a bike are all great ways to look at how durable long-term motor memory is. This is due to where in the brain motor memory is stored. Let’s look at the difference between short-term motor memory first and long-term first.

If you need to brush up on brain anatomy, take a look at this other CogniFit article!

Areas of the Brain Related to Motor Memory

Traditional information or episodic memory ultimately ends up in the cerebral cortex, but its journey begins in the hippocampus. This is not the same for motor memory. In fact, it begins its journey in the cerebral cortex. Purkinje neurons located in the cerebral cortex are the source of short-term motor memory. The type of neuron is important to understand because they transmit signals to the cerebellum, the area of the brain that governs movement.

These specialized Purkinje neurons are also important in converting short-term memory into long-term memory. This is because actions rehearsed in short-term memory eventually consolidate and are “moved” into long-term memory. Long-term memory is a bit harder to pin down to one specific area of the brain. A lot of research is currently being done in order to understand how the signals flowing out of the cerebellum to impact rehearsed coordinated movement. Most of the research is leaning towards the work of many interneurons working together. Interneurons are neurons that just transport signals to other neurons, most commonly observed in a reflex response. It is hypothesized that the interneurons lay out a ground map for movement signals to follow when an individual is introduced to a familiar external stimulus.

Motor memory

Motor memory: Remembering to Ride a Bike

All that time spent on as a kid on sidewalks, driveways, and cul-de-sacs with training wheels on your bike allowed for your brain to begin building and assigning interneuron pathways for your cerebellum to outflow muscle information to your legs. The general gross motor movements were different than walking, and your body needed to acclimate to the new challenge.

The first day you sat on your bike it was hard and awkward, and the second day was probably not much better. However, by the end of the week, you were most likely zooming all around your neighborhood. This is because the rate at which short-term motor memory transfers to long-term motor memory is extremely fast. A few days is the longest amount of time that this transfer usually occurs. This is far faster than typical memory being consolidated within at least a week.

However, if you were to hang up your bicycle for a few years and then take it down for a quick spin you would not forget how to ride it. You may feel wobbly, and a bit uneasy, but your brain and body quickly make corrections associated with balance, also governed by the cerebellum, in order to keep you upright and moving. Those slight adjustments are the work of your short-term motor memory impacting your long term memory.

Motor memory: Memory of Playing the Piano

Remembering to play the piano, or any musical instrument that requires dexterity is also similar to remembering how to ride a bike. Although, with music, there is a non-motor memory component: how the piece sounds.

Sitting down at a piano might not conjure up that specific Bach concerto you spend months working through, but allowing your hands to run up and down the familiar keys will allow you to remember the piece or the composer. Music and sound has a very distinct impact on our memory and hearing how something sounds often works in a cyclical fashion to make the hands move more smoothly across the keys. However, just the like the bike example, it will take time in order to gain speed when playing.

Motor memory: Remembering to Catch a Ball

Unlike the other two examples, catching a ball is a better example of short-term motor memory. The overall outline of how to catch a ball remains the same, thanks to your long-term motor memory. However, your short-term motor memory is what allows you to process how the other person is throwing you the ball. This is equally true with how you are throwing the ball back. Perhaps you misjudged how far away you were from one another. Within a few throws, you will be able to throw consistently to each other, as well as understand how to catch a “trickier” or unexpected throw. The speed at which you are able to do this is evidence of how well your brain and muscles communicate.

Motor memory

Motor Memory and Age

In many neurodegenerative diseases, memory is greatly impacted. Many early symptoms of dementia and Alzheimer’s disease include loss of motor memory. In these cases, motor decline is coupled with cognitive processes decline, which suggests that the two are related.

New emerging therapies and treatments for Alzheimer’s patients include a physical exercises component. Exercise releases a handful of neurotransmitters (types of neurotransmitters) in relatively high doses, and this increase in neurotransmitter activity in the brain could be what makes this treatment beneficial. Dopamine has a high number of receptors in the cerebellum, which governs motor control. The increase in dopamine in that area of the brain during exercise could reinforce the motor memory map laid out by interneurons extending from the cerebellum. This alternative to pharmaceutical intervention may even help us further understand why long-term and short-term motor memory differ from our typical memory schematic.

Have any questions? Leave me a comment below!

Research debunks IQ myth: cognitive ability requires more than one measure

Research debunks IQ myth: cognitive ability requires more than one measure.

After conducting the largest online intelligence study on record, a Western University-led research team has concluded that the notion of measuring one’s intelligence quotient or IQ by a singular, standardized test is highly misleading.

The results showed that when a wide range of cognitive abilities are explored, the observed variations in performance can only be explained with at least three distinct components: short-term memory, reasoning and a verbal component.

What Happens To The Aging Brain

Deterioration of the brain sneaks up on most of us. The first clue might be hearing loss, especially in the higher frequencies. We may be forced into bifocals, even trifocals.

But the most serious signs of deterioration occur in the brain. As we age, our reflexes slow. We walk and act slower. We even talk slower. Our memory starts to fail, such as the short-term memory ability that is so crucial for learning new things.

CogniFit Brain Training Mental Number Application

The CogniFit Mental Numbers Application offers you several exciting tasks to challenge your brain with and develop a wide range of cognitive abilities such as your focus, planning, working memory and visual short-term memory. Having the capacity to easily play in your mind with numbers is a key skill that you want to possess. We are constantly surrounded with numbers and calculations in our daily life. This application offers you a fun and easy way of becoming faster in mental math while training many basic cognitive skills needed for many other tasks in your daily life.