MEMORY CONSOLIDATION

Introduction

Consolidation is the way by which memories are processed. That is when you have some experiences in the short term memory and the memory isn’t consolidated so it would never convert to long term memory. In other terms, this is a narrowing down process through which short term memory is converted into the long term. The process involves neurons in the brain undergoing protein synthesis. These proteins glue all the memories together.

There are two major processes that lead to the final consolidation. These are synaptic consolidation which takes place within immediate hours of learning and encoding while the other is system consolidation where hippocampal memories are independent of hippocampus storage after a certain period of time. The long term potentiation is the consolidation convicted of increasing synaptic transmissions between the neurons.

Long term potentiation is a discrete phenomenon linked to the synchronous neuronal firing of the same group type to induce sensitization for future retrieval. The additional memories create more connections by rearranging them and redirecting them to their specific points. A laid neuronal pathway will create less resistance path for the further flow of information. This is concerned with protein formation for the consolidation.

Basics of Memory Consolidation

The memory is stored and functioned in two major ways. One is encoding while the other is the transfer of information. There are two forms of encoding which as well are labelled as short term and long term. While the transfer of memory from the short term requires two basics which are rehearsal and Organization of Information.

There are three basic stages through which memory forms. These are:

  • Encoding: This refers to how sensory inputs are transformed into a kind of input that can be stored as in the form of memory.
  • Storage: This represents how to retain the encoded sensory information you get through your sense organs.
  • Retrieval: This accounts for how you get access to the actual memory stores in your brain. 

Transfer of Short term Memory to Long term Memory

There is always the existence of interference between the storing information and that of the competing information. When we aren’t retrieving the facts and figures we are paving the path for the particular memory to decay. The non-declarative memories tend to be more volatile than the declarative ones. The non-declarative memories can be incorporated into permanent stores by constant practices and repeated procedural conditioning.

The formation of long term declarative memory can occur through several processes. Like making connections between the information, the newer ones have to be linked to the older ones. Acting upon the new information to bring about a better progressive result. We, humans, are known to make connections with the existing stored information in the storehouses. The process of integration is widely known as consolidation. Here we deal with two straightforward yet comprehensive terms. These are:

  • Metacognition which explains our thought process mastering our thinking capabilities in the first place to its right.
  • Metamemory stages which explain how processing our memory houses reveal the improved memory types. These are sub categorical divisions of the metacognition.
  • Rehearsal refers to the repetition of the same information to keep it to a significant place through practice effects. Rehearsal can be elaborative or maintenance. Elaborative is when concise parts are opened to an extent to find connections and links for meaningful expression while maintenance is just stitched to repetitive rehearsals

Shreds of evidence of consolidation

It is vital to state that conscious memories are formed through consolidation which is initially stored in the storehouses namely the hippocampus and neocortex. Then the hippocampus gets out of the sentence and the consolidation is rather restricted to the neocortex after a certain time. Early consolidation examples were studied while studying retrograde amnesia which is known to affect the hippocampus overall. There are certain genetic tools like optogenetic which are used to study consolidation as a whole. 

The historical aspect of memory consolidation

Quintillian expressed his views in relation to consolidation. He noted over a period of time that a single night is enough to strengthen up the memory a bit. Later a whole data was explained in the clinical data presented by Ribot’s Law of Regression in 1882. Later William Burnham found the integration between the neurological and psychological sciences linked to memory formation.

Working of Memory Consolidation Process

The memory consolidation works by the process of potentiation. The process is integrated through a synaptic workforce and requires the conduction of information from neurons to neurons via the help of neurotransmitters. The greater the number of times through which the signals pass from a certain synapse can be termed as potentiation. This holds on the learning and memory process onto a greater gateway.

Continuous rehearsal and revision strengthen the networks existing between the compartments. This can be easily correlated to your studying strategies. Your often recalling patterns help you remember a certain thing for a longer period. This causes repetitive neuronal firing which can even be experienced in the later future times. This marks the accuracy and precision with which you’re able to remember a certain thing.

Standard Model of Synaptic Consolidation

This shows a discrete referral to changes in protein synthesis linked to the process of consolidation. Certain alterations are found such as changes in the membrane potential through certain transduction cascades. These are linked to the production of certain transcription factors that are directly linked to the production of synaptic proteins. Molecular cascades in the early spans are susceptible to disruptions as these are linked to genes expression. Mutations through the drugs can be a single cause.

Multiple Trace Theory

This theory is founded on the basis to put forward the discrimination between the two memory types: episodic and semantic memory. It says that the hippocampus is the mandatory part which occupies the brain in terms of memory retrieval for the episodic memory type. Certain links are established between the hippocampus and the neocortex during the process of conversion.

Neurocomputational Models of Consolidation

It states how the purpose of consolidation is revealed when there is knowledge acquisition at the greater front. This explains how the memory gets stored in the hippocampal region which works at a greater pace and then shifts to the neocortex which is rather slower. The hippocampal forms connections to multiple regions existing in the neocortex.

Speeding Up Memory Consolidation Process

Rehearsal and strategic learning can improve the accuracy with which the short term memory is consolidated into the long term. Creating links and integrating things into the existing knowledge is for this reason considered to be an optimistic mode of learning. There is rather a preference given to concept building in comparison to Rhode learning in schools and higher levels. This lets links be created incorporating memories and new knowledge at a higher pace. Adapting to a pro-technique can help you in life long acquisition of memories timely.

System Consolidation

It is stated in the very beginning of the article that the memory reorientation can be seen in such cases. The reorganization of the memory is seen from the hippocampal region to the areas of the brain called the neocortex. This is a dynamic process that is linked with precise memory stabilization. It is the reshifting of the memory

Sleep Consolidation

5 different sleep stages are different in their EEG patterns. The REM stage is when the person dreams about something, hence increasing the learning procedure. Insomnia patients are having problems with memory consolidation as they are sleep-deprived individuals.

The cells of the hippocampus that got activated during the encoding of the new memory too get active during the sleep. This is done to achieve consolidation and conversion of short term broken memory to a long term stored memory into the storehouses. Hippocampus is advanced in collecting new information for a temporary basis until it is calculated and transferred to neocortical representation in the brain.

Sleep can be divided into two main phases which are REM (Rapid Eye Movement) and NREM (Non-Rapid Eye Movement) sleep. Holding on to the memory implication there is rather an establishment of links between hippocampal and cortical regions of the brain. REM is also known as active sleep which elicits profound neuronal activity in the brain. This works through the action of neuronal plasticity.

Though slow-wave sleep or NREM is known to produce a low level of acetylcholine that aids in the consolidation process building the learning regime.  REM sleep is particularly related to procedural learning consolidation when researchers have been carried out on sensory and motor-related tasks. Synaptic consolidations have more role played in such a case when compared to system consolidation. 

Organization of Information

It depends on every individual what marks does he or she needs to create to pull out the consistent organization of information within their heads. Certain techniques cause better retrieval and organization as in the form of mnemonic devices, reminders, and forcing functions. 

  • Mnemonics help to reflect the memory at a better pace and allow sound integration to the other associated memory counterparts. 
  • Reminders are external aids the person might seek to help him remember certain tasks easily. Like setting up an alarm note on the phone or jotting down things in the diary.
  • Forcing Function which allows signaling or link creation to certain non-vital things which you do remember as a part of other vital information.

Retrieval

This can further be broadly classified into two categories. Retrieval for short term memory and retrieval for long term memory. The short term memory owns two serial and parallel processing. The earlier part explaining the activities carried out in synchrony to the next while the latter processing refers to managing the operation of multiple processing in a single go.

Importance of Consolidation

Memory exercise is what consolidation refers to pinpointing to the fact of encoding and retrieval as a whole. You’ve been learning quite a few math fundamentals back in school which needs the greatest upgrading and consolidation to be accommodated most smoothly. This opts to bring in the destiny of leading with an A grade in the statistics exam.

It’s rather researched that an average student can grasp just about 25% while he is in the lecture listening to the teacher carefully. The rest 75%  needs a whole lot of consolidation to get to the memory storehouse where they deserve to be. We tend to slip off the information which is no use to our brains. 

Memory consolidation, when studied through the perspective of psychology, relies mainly on a healthy body and brain. Though we lose memory as we grow which is related to Age-related memory deterioration but can earlier be conversed at the level of diseases like Alzheimer’s and other relatable neuropathies. Certain sedative drugs, anxiolytics, benzodiazepines also pay hands in hands for such deterioration with time. Certain lifestyle habits are convicted to pull in the mechanism of long term memory consolidation without costing you much.

This is the main reason while schools are obliged to send back students at home with homework so that the classwork which they had gets revised with time. This will cause an earlier consolidation which is later strengthened by tests and examinations held in charge of regular retrieval made mandatory onboard.

Stages Of Memory Consolidation

Certain stages are linked to memory consolidation but each stage is linked to the existence of the time since the memory is incorporated into its existence. Memory consolidation is just not a matter of days but is linked to the consolidation process for weeks, months, and years.

There are different stages of consolidation each linked up with cellular mechanisms and brain systems. Hippocampus and other relatable regions are adjourned to produce memory consolidation. This is known that early memory storage takes place in the hippocampal region and is later transferred to the neocortical areas. These areas are entorhinal and parietal cortices.

Modulation of Consolidated Memory

This adaptive function takes time to recruit information and to consolidate it into the long term memory. The neurobiological systems are not quick in being responsive to such facts. There are researchers and evidence which lays down the fact that the adaptive function of the consolidated memory is achieved through certain endogenous processes. Certain drugs serve to be a stimulator for the limbic system and brainstem reticular system. It favors neurohormonal influences for certain future neurological activities.

Studying Memory Consolidation

Certain neuroimaging methods help to study the process of consolidation. The main methods are Positron Emission Tomography (PET)  and Magnetic Resonance Imaging( MRI). This will help the professional to discover the actual activity ongoing on the structures like the hippocampus and medial frontal cortex. The neuroimaging helps to build the connection between the hippocampal and associated regions. The study guides are tested for semantic knowledge implying the positive research approach. Memory enhancement through the process of consolidation is rather the greatest blessings help us to keep in mind the childhood journeys to the teen looks.

Summary

Memory consolidation involves converting short term memories into long term memories.

The consolidation process involves three steps of encoding, storage, and retrieval.

Encoding is the modification in the sensory inputs so that they can be stored.

Storage involves retaining the modified sensory information after encoding has been done.

Retrieval is accessing the stored information after some time.

Memory consolidation takes place in the hippocampus and neocortex of the brain.

Memory consolidation occurs by the potentiation of synaptic pathways. The greater the potentiation of certain synaptic tracts, the better is memory consolidation.

These synaptic pathways can be strengthened by rehearsal or retrieval of memory again and again.

The standard model states that potentiation causes certain changes in the neurons that may involve changes in protein synthesis as well as changes in the membrane potential.

Multiple trace theory explains how episodic and semantic memories are interlinked.

The neurocomputational model of memory consolidation states how the hippocampus works faster than neocortex in case of memory storage.

The process of memory consolidation can be improved by certain therapies, rehearsals, making links between the things, and some other techniques as advised by the neurologists.

Sleep consolidation can be divided into REM and NREM stages. REM sleep is associated with procedural learning.

Information is organized using certain techniques before its consolidation. Organized memories are always easy to recall and difficult to forget.

Memory consolidation is a long term process divided into certain interlinked staged that have been studied in the article.

Memory consolidation can be studied via different imaging techniques like PET scan or MRI studies.

References

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Image sources

  1. https://en.wikipedia.org/wiki/File:Modal_model_of_the_mind.jpg
  2. https://en.wikipedia.org/wiki/Memory_consolidation
  3. https://commons.wikimedia.org/wiki/File:Brain_regions_involved_in_memory_formation.jpg
  4. https://commons.wikimedia.org/wiki/File:Simplified_Sleep_Phases.jpg