Why do we remember our favorite song’s lyrics and why can’t we remember what we read in the newspaper in the last couple of days?

Why do we remember our special friends even after not meeting them every day but tend to forget what we read yesterday for the exam?

This all is explained by the functioning of the brain and how the memory processes information and how we retrieve it.  The brain is a wonderful organ but  trust me , the process is not as simple and flawless as it looks!

In this article we’ll try to understand how our brain processes a memory and how it decides the duration of that memory to be stored as it actually plays a huge role in our everyday lives.

Memory is basically the flashback of the ability to remember past experiences and information. It is an important essence of our everyday functioning. Without the memory of the past , it’s almost impossible to survive in the present and the future. Imagine , how would you feel if you wouldn’t remember faces of your friends and family , you wouldn’t be able to operate recent technologies like cars and mobile phones , you actually won’t be able to maintain your personal identity. Sounds quite scary right. But think how our brain stores so much data and how it filters the information from the data. Let’s decode it!

Memory involves various parts of the brain working together and follows three basic steps :  encoding , storing and retrieving the information.

These three make up the basic memory functioning. To understand more , let’s look at them separately.

MEMORY ENCODING

The brain is a wonderful organ but it still cannot remember everything we listen , watch or read. Whenever an information strikes our brain , it needs to be changed into a specific form in which our brain can read it and can store it. This is called memory encoding. But to retain that information , it needs to be stored in a more stable form of memory. It has to convert a sensory input into a neural kind of code to store it. The processing is obviously influenced by factors such as attention , repetition and relevance.There are two types of encoding :

• SEMANTIC – This depends on the relevance of the information. For example – you tend to remember a concept of physics better because you’ve understood it and it’s relevant to you so it is structured better and easier to remember.
• VISUAL – This depends on the visual appearance of the memory. The brain processes information like color,texture and shape. There’s a different sketchpad where the visuals get stored in the brain.
• ACOUSTIC- It depends on the sound of the information and processes features like auditory voice , pitch , tone or rhythm.

MEMORY STORING

Memory storage refers to the storage of information for its retrieval. It plays a vital role in survival , problem solving and maintaining your personal identity. We store different types of information in different types of places in memory , depending on what kind of information it is. For example – explicit memories and semantic memory gets stored in the hippocampus , the neocortex and amygdala while the implicit memories get stored in basal ganglia and cerebellum.

For better understanding , the memory is also classified into three types , that is  Sensory memory , Short term memory and Long term memory.

In sensory memory , we receive information from stimuli which can be from auditory , sight or touch whereas short term memory is the memory for which we are actively thinking and as the name suggests it has a very small capacity.

Long term memory refers to the ability to store and retrieve memory over long periods of time , it consists of two types which are explicit and implicit memory. Explicit memory is the events that happened to you and also includes facts and information while implicit memory is the habits and skills we achieve through repetition and practice.

MEMORY RETRIEVAL

This refers to the ability to access past information and ability to get out of the previous stages. It has to be triggered by an internal or external stimulus. The memory retrieval can be differentiated into three types as well – Recognition , Recall and Relearning.

Recognition is the stimulus that has occurred previously like a familiar face. Recall is basically when you try to remember something without cues like a phone number. Relearning is remembering something that you have previously forgotten and it’s faster than quick learning because you still have some traces of that particular memory.

MEMORY CONSOLIDATION

Memory consolidation is the process of transforming information from a temporary memory into a stable and long term memory. It gets initiated with a gene expression dependent phase that lasts for a period of time.This is known as cellular or molecular consolidation which represents the fragile state of memory. Memory that relies on the hippocampus is not stable after this phase. If the hippocampus is inactivated during the phase , the memories are lost.

This mechanism is studied on rats trained in Inhibitory avoidance task (IA) , it is a fear conditioning task in which rats are encounters a shock hence learns to avoid it when represented with that context later times.The advantage of this task is that it is learned in a single trial, thus allowing the identification of rapid changes occurring in the brain after encoding and the follow up of their progression over time.Focusing first on the dorsal hippocampus, a region required for the formation of contextual associations, we have found that, in this region, the activation of the pathways mediated by the transcription factors cAMP response element binding protein (CREB) and CCAAT enhancer binding protein β and δ (C/EBPβ and δ) are required for IA memory consolidation. Hence it is observed that CREB-C / EBP is a molecular pathway of memory formation.

The upstream and downstream of CREB-C/EBP is important as it offers the targets that are used to strengthen and weaken memories.

STRESS MECHANISM

Have you ever thought about- why you remember emotional events rather than neutral events ? Those neutral events are actually quickly forgotten.The emotion can be positive or negative or maybe traumatic experience like anxiety and PTSD.

That is because neurologists believe that level of stress follows an inverted U relationship with memory retention. Increasing level of stress has a longer memory impact. Accordingly, it has been found that the levels of the stress hormones noradrenaline and glucocorticoids, which are released in response to stress, mediate and modulate memory retention according to an inverted U-shape curve.

Recent studies have also shown that this mechanism activates downstream of glucocorticoid receptors (GR) and implicates long term memory formation.It emerged that after learning GRs regulate several intracellular signaling pathways known to be required for memory consolidation.

WHY DO WE FORGET INFORMATION?

Forgetting of memory is when our brain fails to retrieve information. It happens due to various reasons like when we don’t pay attention to an information or do not connect with the information , we often forget it while retrieving it. Sometimes when we don’t recall the memory so the strength between the neurons fade away and memories start to decay. Hence this concludes that the more we recall , the more the memory becomes stronger.

Sometimes there is an interference of other memories between two similar memories or maybe when new memories overwrite the old ones. Have you ever forgotten your keys somewhere? Probably yes! Because it happens to all of us , this is a classic example of retrieval failure. There are times when there is motivated forgetting like you actively want to forget a memory like a traumatic experience , this can be via two forms – consciously or unconsciously.

However , forgetting memory is a necessary process as it helps to filter out the information from our brain and helps to prioritize what we actually need.

HOW TO BOOST MEMORY?

There are so many strategies with which you can boost your memory.

1. Practice and Recall The more you recall , the more your memory will get strong. So if you want to remember something for the long term , you will have to keep recalling it.
2. Make associations So many times , while remembering we connect dots with something random like mind maps and we try to remember it by associating with it.
3. Good Sleep Your brain needs a good rest too , so getting enough sleep will help you to retrieve your memory easily.
4. Writing Things Down Writing things impacts your brain more actively , so try to write or note things down for remembering it well.
5. Healthy Habits Eating healthy and exercising regularly helps the blood flow properly which stimulates the brain and promotes growth of new brain cells. Try to include omega 3 fatty acid in your diet.
6. Learning in small portions Breaking information down into small chunks is an approach called microlearning.

After all, remembering a large amount of information can be overwhelming. This, in turn, makes it harder to retrieve and store information in your long-term memory. With so much study , we have gotten information about almost everything but still there is a long way to go. Neuroscience is interesting and complex at the same time. Hence we can always  boost our encoding , storing and retrieval of information.