Memory – the foundation of all human activities

“Cats have it and dogs have it, everybody have its own way to survive.”  - Old sailor wisdom

Every animal has its physical posture together with its basic instinct to survive in this world. Like the cat have claw and night vision and very good of automatic balance while falling, it suit for night activities and living on the tree along. Dogs have loud barking and poor sight in night and cannot climb the tree while in danger, it have to unite in group to make a living at land. There is nothing good or bad about their tools to survive as long as it can serve the purpose required. Every man has its own way of living too but not so obvious as we can see from other kind of animal.    

Imaging a small snake had just break of it crust of egg already have the ability to find the food for his survival. Small sea turtle have to make his way to sea to avoid their extinguish. Human are particular vulnerable to compare with other animal. We are protected by our parent to learn the way suitable for us to survive the challenges of live. These learning processes and materials are so diversity that we have many kinds of culture and living in the world. Every man while born is equipped with same reflex on the body to reflect some basic survival requirements like the infant can hold his breath automatically while his face muscle felt water. These reflexes will fade away while our memories found it not suitable or simply because we did not use it in time like elder baby will choke by the water on face if he did not get used to the process. Beside these human reflex which are the remnant of our ancient history, we have to learn our way of living by memories. 

Our memory is selective with our own preferences which consist of four parts: sensory memories, Short term memory, Long term memory and Working memory. These four kinds of memory dominated all kinds of human activities but we just get used to it too often and too long (often without our own conscious awareness) since our childhood. If something has gone wrong, we won’t be able to correct it by ourself. So it is important that we should fully understand its function and limitation so as to enhance our abilities in all kinds.    

1. 1.     Sensory memory comes from our five sensory organs after an object is perceived. Most part of the world is out of touch by our hand or body and even less part of it could be tasted by our mouth. The smell sense is no better than few steps away for human and most of the time have to depend on the luck wind is coming our way. These three senses are usually closely monitored by our parent in our infancy age to guide us from hurting ourself.  Our cognitive processes are mostly depending on our ability to look for valuable clues around us or to detect what is strange to our eye. Once we noticed something interest we will try to remember what it looked like in an effort just within a split second of observation to memorize by sight (Iconic memory). With very short presentations, people often report that they seem to "see" more than they can actually report. Those items they can report are caught by their attention and those they cannot tell are caught by their subconscious. Iconic memory briefly stores an image which has been perceived for a small duration for about 0.2 seconds. 

Our ability to construct the world we know by hearing either from the context provided by our teacher or by imaging ability of our own. Echoic memory is another type of sensory memory of hearing that briefly stores sounds that have been perceived for short durations about 2 seconds. The echoic memory last longer time than iconic memory is because verbal communication of human have to construct other people’s meaning word by word in a recognizable grammar way. One word or one sound cannot properly express our intention, like the old saying “one picture is worth than thousand words”. Just by one look, we can tell more story than 2 seconds listening because picture provide more clues which can arouse our attention through proper training. 

Our five sense organs are the interface of human and the world. Everything we knew started from these sense 7 by 7. Systematic memory consists of all sensory memory we had at that particular time and most important is together with the emotion we had at that time. The emotion remembered with the event provides the motive to react in next occurrence of same thing. If no emotion occurred, our training or learning is most probably wasted. The animal has most sophisticated sense is elephant. Imaging the biggest animal lives on land but has the most sensitive feeling of all. Why the biggest mess should need to notice the slightest danger? Does that imply something we should be aware?

1. 2.     Short-term memory allows recall our sensory memories for a period of several seconds to a minute without rehearsal. Its storage capacity to most of us surprise is very limited: Experiments showing that the store of short-term memory was 7±2 items (" George A. Miller (1956) The magical number 7±2"). Modern estimates of the capacity of short-term memory are even lower, typically of the order of 4–5 items; however, memory capacity can be increased through a process called chunking. For example, in recalling a ten-digit telephone number, a person could chunk the digits into three groups: first, the area code (such as 123), then a three-digit chunk (456) and lastly a four-digit chunk (7890). This method of remembering telephone numbers is more effective than attempting to remember a string of 10 digits; this ability that we can chunk the information into different meaningful groups is very important in our recognition process which we will notice later in the chapters to come. 
2. 3.     The storage in sensory memory and short-term memory generally has a strictly limited capacity and duration, which means that information is not retained indefinitely (if we don’t forget it at once, we will soon be overloaded with noise). By contrast, long-term memory can store large quantities of information for potentially unlimited duration (sometimes a whole life span). Its capacity is immeasurably large. For example, given a random seven-digit number we may remember it for only a few seconds before forgetting, suggesting it was stored in our short-term memory. On the other hand, we can remember telephone numbers for many years through repetition; this information is said to be stored in long-term memory. The numbers of repetition decide the tendency of our brain to remember it. Scientist had proved long term memory can only be established after two months period by the electrical shock applied to participants which cause them to forget anything happened or learnt within two months, but the knowledge and skill they had two months before are still intake.  

Long term memory consist of two part : Procedural Memory, like fasten the shore string or get up from bed. We knew exactly how to do it but cannot tell where, when and why we can do it. For those long term memories of what, who, where had happened that date we called it Episodic Memory or Context memory, like the memory of our wedding ceremony. 

1. 4.     Working memory consist of all memories we had to do the work for us. Working memory of our brain has great capacity as the knowledge and experience we had also grew as our age increased. Our working memory consist of those memories still need to be challenged by our current context or need to be rationale of current environment or the key points need to be concentrated or need to be brought out to our conscious to take action/decision correctly. If the appraisal time is limited for our brain, this process could be very exhausted to a young man. Temporary mental exhaustion is a genuine and common phenomenon. Complex thought and intense concentration require more energy than routine mental processes. Average adult human brain weighs about 1.4 kilograms, only 2 percent of total body weight but it demands 20 percent of our energy which varies from person to person depending on age, gender, size and health. While I was a student, I cannot concentrate on any topic over 5 minutes whether I was interested or not. After that, I just feel very sleepy. Although working memory increased as aging, we only feels more comfortable in things we are more familiar with. The more familiar, the more relaxed. So in every culture, the rituals consist of an important part of all religions. We get used to doing something seems unnecessary to fulfill our purpose, doing some small talk of totally nonsense to find the peace in mind, singing non communicable song to calm our soul, these activities had go down below our conscious into our subconscious or unconscious mind. 

The most amazing thing of our brain is it is actually simplified everything for us without our awareness. The things goes below our conscious take out the mental burden of us to fit us into more complicated and sophisticate operations in our personal growth also in our civilizations progress. 

1. 5.     Subconscious is our long term memory accumulated in our brain which need not be explicit or explainable to our conscious. We do not do any judgment at it correctness anymore. It works as our working habit without awareness. If we do not have the long term memory, we would not have any awareness of the situation which seems need our special attention. This often is the case for an unexperienced cadet; we called it “Glancing: looking but not knowing”. The communication channel of our subconscious to us is through the emotion we have, not in any context in ration. We can rational the feeling in later stage, but we cannot describe why it happened at the time of its occurrence. It is a reminder of our past experience, not any story can be told by words or wrote in letters while we most needed its work. Subconscious just give you the feeling make you feel weird in someway. The motion you are conducting suddenly lost its urgency feeling or the muscle strength to carry on. We feel something wrong but what?  Subconscious is not confined in the brain only but may also reside in our muscle too like some insects have fused ganglia. During each time of repetition of same operation, neural connections between the brain and muscle had been reinforced and getting stronger and quicker. Once same stimulus percept, human will make the reaction without his conscious awareness by so called muscle memory, these usually consist of several actions in sequence. Sometimes we called it Procedural Memory, like fasten the shore string or get up from bed. We knew exactly how to do it but cannot tell where, when and why we can do it. For those long term memories of what, who, where had happened that date we called it Episodic Memory, like the memory of our wedding ceremony.   

In summary: our memory tree 

Sensory Memory: can last 0.3 – 2second for the pictures we see or the sound we hear…. 

Short Term Memory; can remember“7±2”massage chunk, lasting to one minute without rehearsal.

Working Memory  : Sensory +Short Term +Long Term Memory， lasting by repetition numbers

Long Term Memory : may last lifetime，can survive the electrical shock after two months period。

Procedure Memory: easy job without noticeable by oneself. 

Emotional Memory: the feeling from our subconscious while we are doing something 

Context Memory : which you can say，can understand，sound logical，does not mean it is true。

We can see from the memory tree below, the world is constructed by our working memories as the word “Structure” stands. Our long term memories consist of two parts: the explicit memory and Hidden Memory. Explicit Memory is the memory we need some context to explain when, where who, which and why we had in our brain, like our first date our wedding day, something….... The Procedural Memory is something we only want to know how to do in sequence but did not care about when, who and why we do it, like button up our shirt or tie up shore strings, etc……..        

Explicit Memory is explicit because we can clear define when and where it begins and what had gone through in that event and why it had ended in that way, it is a story type memory. Hidden memory is hard to explain what and why for it can be happened in very short interval without our conscious intervened. Even we want to explain it in details; most people will not able to find the way to properly describe it. Like shooting in arrow is an easy job for a tribe people, but he may have the problem to teach you how to do it. Sometimes when we are doing something a sudden feeling come flushed our mind. We feel some kind emotion in actions as we are just doing. These feeling sometimes are very strong so we can sense the difference of our physical body reaction before and after they are coming we call it emotional memory. What we don’t really know is emotion is with us in all our activities in some way we knew it or not.      

Hippocampus: Emotion Generator 

Our brain retains different memories through different mechanics. Short-term memory is supported by transient patterns of neuronal communication. Long-term memory, on the other hand, is maintained by more stable and permanent changes in neural connections widely spread throughout the brain. Short term memory is the awareness of the environment and long term memory is the context of the world around us together with the emotion.

The hippocampus is believed to be the center of information from short-term to long-term memory and probably where the working memory starting from. Without the hippocampus, new memories are unable to be stored into long-term memory, as learned from patient Henry Molaison(HM) case after removal of both his hippocampi. He cannot remember anything over 20 seconds; but he can read and talk normally. The doctor he met every day always look like a new friend to him. He cannot tell the layout of his kitchen or toilet in a paper but he is able to get the drink and take a leak while in need. This is the muscle or procedural memories to him and he cannot explain it either. But anything 2 months before his brain surgery is still remembered and can bring up to conscious level for communication which is the context memory.     

As the emotion play a great part of relationship with other, HM who did not have hippocampus also lost his emotional reaction over new friend. He then lost the ability to know someone new. 

The hippocampus neuron can fire bursts of action potentials which play a central role in cell-to-cell communication. All human epilepsy are originated from hippocampus, thus the muscle memory as well. Study had also shown that the size of hippocampus of a London taxi driver are larger than normal people due to the intensive knowledge of the road map in his mind, while more experienced one have even bigger than usual taxi driver. Knowing this is important as our decision making ability depend on the emotional memory and accumulated knowledge and experience which eventually reshape the size of our hippocampus.        

By our very rare sensory organs and very limited living environment to interact with our brain, nobody has a true and whole picture of the world. Eventually, we are happy about this as long as daily activities can safely carry on. Nobody wants to change it unless something is going wrong due to our very limit conscious capacity. Everything we knew is actually a picture composed by our working memories. If our memories are wrong we will get wrong picture of the world which might reach a dangerous point to our daily activities. In the chapters to come, we will discuss about successful human communication have to make sense to other by our long term memory especially the context memory. Human errors due to knowledge base mistake are failure of short term memory, slips are failure of procedure memory and lapse minds are failure of long term memory. Risk takings and relationship handicaps are failure of emotional memory. Decision making need our memories support. Education, training and mentoring need culture awareness which are close related with memories. The most important part of pressure management, how to delegate, how to work with others and how to change the attitude of our colleagues all need to take our memories tree into close examination, needless to say our memories overloaded will cause mental and physical collapse without our conscious control while we are just incapable for everything or anything.