Brain collecting information…..Human Memory — Part 1

Memory is a diary that we all carry about with us.

Human memory is very important attribute of humans to sustain life. (isn’t it?). Since ages, humans have tried to understand what memory is, how does it work, what are the loop holes etc. (Yes, It has loop holes😉). Extensive successful researches have been carried out on human brain’s to study functioning of our memories.

To understand that, let’s start with the most basic conversation.

Let’s discuss above scenario. Mark and his friend John are having a conversation about some place:-
John: Hey Mark, do you know where Starbucks is?
Mark replies: Oh yea, Starbucks is in XYZ, Block D. You can book a cab and reach there in 30 minutes if you take ABC road. Also, they make very delicious chocolate cakes.

You mustn’t be surprised that how Mark does know much information about Starbucks. Obviously, it has been stored somewhere in his brain and has been recollected and shared when required. Memory is nothing but our ability to encode, decode and recall information, fact and our past experiences that are stored in our brain. Also, our memory has the capability of influencing our current behavior depending upon what information it uses from the past.

Ques) How our tiny brain is very capable of storing so many information?

Ans) Memories are not just processed in one part of the brain. Many important parts of brain are working every second to collect, encode, decode and retrieve day to day data. Different types of memory are processed across different interconnected areas of brain. For explicit memories, there are three important areas of brain; the hippo-campus, the neocortex and the amygdala. Implicit memories most rely on basal ganglia and cerebellum and short term memories rely on prefrontal cortex.

But, before I let you dive with me into the ocean of brain’s functioning of memories, let’s first discuss about the type of memories, a human has.

Here, this blog is divided into two parts:

  1. Types of human memories
  2. Functioning on human memories

Now, Lets start with the first part “Type of human memories”

Types of Human Memories

Sensory Memory

The creation of memory starts with its perception and visualization of environment; means perceiving our environment through our five senses (touch, hear etc). These perceptions last only for fraction of seconds and are part of sensory memory.

  • It allows to register perceptions related to our senses like touching, seeing, hearing etc.
  • Our sensory memory allows a perception such as a visual pattern, a sound, or a touch to linger for a brief moment after the stimulation is over.
  • It is a temporary storage buffer between sensory input and the next stage, short term memory.

Short Term Memory (STM)

Information collected through sensory memory is further stored in Short Term memory. STM has very limited capacity that lasts for few seconds only.

  • It helps brain to recall information temporarily that can be processed at any point of time.
  • As we know, STM has limited capacity, you can increase it by using some tricks and strategies.
  • For example- a 10 digit number like 8950203410 may be too much for your STM to remember, but if divided into parts like phone number 895-020-3410 may actually stay long and help you in dialing the number.
  • STM plays important role in determining if collected information should be converted into long term memory or discarded.
  • The more information is repeated or used, fair chances are those information will be converted into Long term memory.
Note: As we grow old, our STM will have less ability to store information and it will go shorter n shorter further. It also gives less time to brain to decide what kind of information should be converted into long term memory.

Long Term Memory(LTM)

Okay, why our parents used to say “study more so that you will do better in exam or test”? This is because the more we use the Information, the more we will remember it and this how STM is converted into LTM.

  • Unlike sensory and short term memory, long term memory is intended to store information for longer period of time.
  • Despite of our forgetting ability, long term memory manages to store information for years.
  • We can store more information about known subjects in our LTM because of its meaningfulness and mental connectivity with already existing information.

LTM is categorized into two parts.

  1. Explicit Memory
  2. Implicit Memory

Explicit Memory / Declarative memory

If someone asks me what is capital of India? Without a doubt, I will say “Its Delhi” and this memory is called Explicit memory (EM).

  • Explicit memory is about facts & events, and refers to those memories that can be consciously recalled.
  • When you think of memory irrespective good or bad, most of it you receive from brain is explicit memory.
  • Explicit memories are often associative and linked together inside the brain — For example, If you think of Old Monk beer, it’ll bring up all related information about the drink through associated memories.

Explicit memory is further divided into two parts:

  1. Episodic Memory
  2. Semantic Memory

Episodic Memory

  • Episodic memory is related to events, experiences that happened in our life.
  • It stores crucial records of our experiences and events happened in the past and helps in reconstructing those experiences as and when needed in time.
  • Any past event in which we’ve taken part and we remember as an episode is episodic memory- For example, Our memorable trips and your sibling’s marriage event.

Semantic Memory

  • On contrary, Semantic memory is created through our learning and general knowledge about the external world.
  • Its all about the facts, concepts and knowledge of the world that we have collected over period of time. (not connected with personal exp.)
  • Types of food, capital cities, social customs, vocabulary, understanding of mathematics, etc. come under semantic memory- For example, Asia is the biggest continent in the world.

Implicit Memory

  • Another type of LTM that differs from explicit memory as it doesn’t need factual information and doesn’t require conscious thought.
  • It refers as unconscious memory and allows us to do things mindlessly.
  • This memory is not very easy to verbalize as it can been seen in our actions effortlessly. Skills like drive, eat, read etc. are part of implicit memory.
Note: You must be wondering that remembering driving skills should be explicit memory. Right? You are correct, but our ability to improve our driving skills comes under implicit memory.

So, as agreed this is a little introduction on Human memory we got inside our brain. There are other many more like Autobiography memory, Spatial memory etc. which are stored as well.

In my next blog, I will brief you about “how brain functions on encoding, decoding & retrieving information in form of memories”

I hope you’ve enjoyed reading :)