If we need to compare the way in which our memories are stored in the brain with actual physical storage, the analogy would be a puzzle rather than a book-shelf. The information we receive through the five senses is not just put in a dedicated place in the brain – it’s also integrated and consolidated.
Memory consolidation refers to the time-dependent processes that are activated in dedicated brain centers that include receiving, encoding, classifying, and storing the information received via the sensory organs. These processes depend upon the significance and time span of the particular memory, as well as the depth of its emotional impact.
By transforming the learned experiences into long-term memories, the consolidation of memory enables us to process our environment, improve behavior, and give context to our lives.
What Is the Role of Memory Consolidation?
The main role of memory consolidation is to turn short term memories into long term ones, supported by the chemical and structural changes in the central nervous system.
More specifically put, consolidation of memory is the process that makes the memory more stable and permanent.
How Does the Consolidation of Memory Work?
As we learn more and gain more experiences, information, and memories, the synaptic connections multiply in the brain more and more, reinforcing the long term memory.
For instance, the more and the longer we study a lesson, the easier it will be for us to recall the facts at some later point in time. Or, we could compare the role of the synapses in memory consolidation with a path – the more we walk along the same path, the stronger is the trace we leave behind which could later help us return to where we were more easily.
What Are the Stages of Memory Consolidation?
The processes of memory consolidation are developed in three stages:
- Synaptic consolidation of memory
- Systems consolidation of memory
- Reconsolidation of memory
Synaptic Consolidation of Memory
What Is the Role of the Synapses in Memory Consolidation?
Our memory is formed when specific groups of neurons are reactivated in the brain, i.e. the synaptic connections between neurons are strengthened, or there is a formation of completely new synapses.
The synaptic strength also changes according to the number of stimuli received during a learning process. These changes contribute to the processes of learning and memory by supporting the synaptic consolidation of the information stored in the dedicated brain area. The more frequently the signals pass, the stronger the synapses of the brain cell get.
Systems Consolidation of Memory
The hippocampus is the part of the brain where the consolidation of memory takes place in the second stage of the process. It helps transfer immediate thoughts and sensory data into short and long term memories and is responsible for the processing of the knowledge associated with spatial awareness.
The memory remains in the hippocampus for one week after learning. The information received from the sensory stimuli in this brain structure can be encoded as semantic (meaning), visual (images), as well as acoustic (sound) memories. The consolidation of memory occurs when the memory is slowly transferred from the hippocampus to the neocortex of the brain.
Namely, the hippocampus receives neuronal connections from the primary sensory areas of the cortex, after which it translates the stimuli and relates them to similar information from past knowledge that has previously been stored. Sleep is also one of the main contributing processes for the consolidation of memory in this process.
What Is the Specific Role of the Hippocampus in Memory Consolidation?
The hippocampus supports the transmission of immediate thoughts and sensory data into short and long term memories. This structure of the brain is also included in spatial recognition as well as the merging of both short-term and long-term memories. This process of transformation of the recently remembered information into long-term memories is achieved by the creation of stronger synaptic connections between the neuron cells.
Finally, the hippocampus relays the information to all other cortical structures whose function is to assign meaning to the received sensory signals. In order to perform these complex neurological processes, this brain structure mostly communicates with the amygdala and the hypothalamus.
After being consolidated, the processed information from the hippocampus is integrated into the long term memory, i.e. the structures of the cerebral cortex.
Reconsolidation of Memory
By retrieving the stored memory, the human brain ‘replays’ an already established pattern of activity between the neural cells and synapses of the neurons. This activity is previously triggered by events that activate specific areas of the brain in order to process, integrate, consolidate, and store the received information.
The memory is first stabilized (consolidated), then de-stabilized (used), for it to be finally re-stabilized (reconsolidated) again.
After the retrieval, we can reconsolidate our memory. Reconsolidation is a process that can be triggered many times.
The reconsolidation of memory provides us with the ability to adapt and respond to the constantly changing circumstances and surroundings adequately. It helps our brain strengthen our memory and keep its content updated.
Can All types of Memory Be Reconsolidated?
The reconsolidation of memory most often occurs in our memories of simple and repetitive tasks, in the emotional, declarative, incidental, spatial, drug-paired, and motor memories, as well as the memories formed in the hippocampus and the amygdala.
As time goes by, the reconsolidation becomes more difficult to be activated. Namely, the memories are harder to be evoked with the passage of time, because the neuronal memory traces in the brain are less and less repeated in the process of retrieving memory.
Fun Facts
Did you know?
- Encoding, storage, and retrieval are the three basic memory processes. They regulate the brain processes in order to determine whether a piece of information received from the sensory stimuli is remembered in the short or long term, or whether it’s forgotten.
- The formation of memory mostly occurs in the limbic system of the human brain. This is because of the fact that the limbic system regulates the most vital cognitive processes: learning, emotions, and memory.
- In order to improve our memory, it would be a good idea for us to strengthen our brain synapses first. This can be done by challenging our mind with puzzles, crosswords, learning foreign languages, exercising (in order to increase the oxygen flow in the brain), avoiding routine, eating a nutritious diet, as well as sleeping sufficiently.
- It takes only a few minutes to a few hours for the synaptic consolidation process to be completed.
- Bilingualism contributes to the wellbeing of our brain because due to the neuroplasticity of the brain, the gray matter increases its density. In this way, our capacity for learning also expands.
- The stronger the emotional content of the memory is, the longer it will remain stored in the brain. On the other hand, while stressful events have a negative impact on memories, positive events are more likely to reinforce our memory of them.
- There is no specific area in the cerebral cortex of the brain that stores memory. There are several brain structures that perform this function. It would also be dangerous if all memories were stored in only one area of the brain. Namely, if that brain area suffers damage, all our memories would be lost forever.
- New neural pathways can be created by our behaviors and habits. Brain training is a classic example of the creation of new neural pathways in the human brain. This, in turn, increases our intelligence.
- The encoding of information can be strengthened by means of association. Namely, the more connections we make with the encoding information by associating it to similar data, the more likely it is that we will remember it sooner and better.
- In cases of damage to the hippocampus, we might lose our memory, which could lead to the need of learning how to read, write, or speak anew.