Long-term memory

Long-term memory

Long-term memory is the storage of our memories from the past, knowledge and experiences that we gained through our life. We can find here everything that our parents have taught us, our teachers, schools, work. All the knowledge that we gained while reading books, talking with friends, watching TV.

Long-term memory is also the storage for our skills, that we gathered through life and some of the things we do subconsciously. These things relate to our occupation or everyday chores (how to drive a car or bike, how to wash our teeth, how to use the keyboard, how to make a piece of furniture, cook, calculate, etc.). Long-term memory also storages our habits.

If we want to learn something new, like speak a new language or play an instrument or make some special dish, we need our long-term memory. With patients with dementia, this memory is preserved the longest, therefore it enables us to communicate with the patient even then, when the memory of every day’s events fades away.

Long-term memory is divided into two different memories: implicit-procedural memory and explicit memory.

Implicit-procedural memory

If we want to make tea, we have to find the tea pot, fill it with water, heat up the stove, wait until the water boils, pick the tea, take the tea bag, put the tea bag in the water for the exact amount of time and put some sugar in the tea. We have to wait that the tea is cold enough, so we can drink it. This procedure is a part of implicit-procedural memory. It is done almost automatic, routinely.

In the same way this memory allows us to recognize sounds and words, so we can understand language or recognize the notes of the song. It also enables us to do some of the things we have once learned automatically, like playing an instrument, swimming, cooking, going home, buttoning shirts, knowing the rules to play board games, handling the phone or TV, brushing teeth.

Implicit memory storages procedure/steps, how to do something and our habits and skills that we gained during our lifetime.

When we learn something new we know exactly “how to do it” and then we internalize it and that is why we do not have to think every time how to complete a task, so we do it automatically and subconsciously. Our brain can store the memory of the process and our muscles function automatically according to that process. Once we learn how to ride a bike or how to drive a car, we do not think about where the break is, but our muscles react automatically.

Basic motoric skills are also found in the implicit memory (example: how to shake someone’s hand, how to hold the spoon and take it to your mouth, how to smile or tie shoelaces.). These skills are somehow imprinted in our muscle memory. Because they are stored in our brain subconsciously, they are recalled automatically- if we hand some object to another person, they will reach the arm and grab it.

Implicit memory contains our knowledge of a certain language (how to say a word, how to make sentences, how to pronounce words in different language, lyrics of songs, sayings, also algebra, and process of calculating). This memory contains also our emotional responses, that we experienced through our lifetime.

Explicit memory

In this memory we can find our knowledge, personal experiences and events from our life.

This memory functions by the principle “top down” of processing information, which means that our behaviour is regulated by mind concepts, conscious processes and knowledge. Mind concepts are regulating our sensory perception. So we permanently storage organized information. Information can be permanently saved within minutes they were perceived through our sensory perception.

Explicit memory can be described in detail, that is why we also call it declarative memory. While when dealing with implicit memory, that is not always possible, because we do things automatically.

Explicit memory is conscious and planned memorizing of facts (semantic memory) and personal experiences (episodic or autobiographic memory).

  • Semantic memory

In semantic memory we can find knowledge about historic events, people, knowledge about words, concepts, basically everything we were taught in school and informally, while reading magazines, newspapers, chatting with friends. We are keeping the memories about our family members, friends and acquaintances.

With explicit memory there are connections within certain abilities, that we call cognitive schemes or conceptual networks. Example: when we recognize a tree, we connect it with different areas of our knowledge- woods, deciduous and coniferous tree, maybe there was a storm that once broke one tree, climbing,…

Semantic memory is a memory of concepts, words and meanings; it includes facts, concepts and correlations. Conceptual networks are normally consistent in hierarchic order and categorized. Our cognitive schemes are activated with all sorts of exercises of classifications and categorizing.

  • Episodic memory

It consists of the events of our lives, experiences, emotional imprints, personal experiences. Everything that happened in our life is stored here; it can be our own experience, it can be our friend’s experience, social event, etc. Yesterday’s events and events that happened maybe one hour ago are also stored here.