The Brain Thesis Part VI
The human brain is amazing but at times it can fail. One problem with old age is a forgetfulness that creeps up. Another is memory loss which can lead to forgeting a name or a fact. Another is memory latency, where a fact or information takes a longer time to be recalled. All these can be considered some form of dementia. As we age, our brain cells are slowly dying. The various neural connections are also slowly cut off. Finally, we revert back to our beginning when in the womb and we are a blank slate.
- Dec. 2018
In this article, I will explore some possible problems that arises and how it relates to our working model of the brain. In the case of a slow recall, or something that is just on the tip of our tongue, how is our brain functioning?
If we image the current model of a short term memory and a long term memory interconnected by neurons, there needs to be some structure to the organization of the long term store. A short term memory has a limited capacity. A long term memory has to store all the important aspect of our whole life, from the day we are born to the day we die. This record or archive must be indexed in such a way for speedy recall.
If I want to know the name of a western movie that has John Wayne as the male lead, it must be ”True Grit” or “Rio Bravo” or “Horse Soldier”... or if I think of a title and wants to know who is the actor, the data must flow both ways. In order for the brain to access the information quickly, the path must be short enough and must be readily available. Here is the dilemma. How can all the information be of short paths? There must be some order where the more relevant or useful information are close by and the least useful or less used information are farther away.
As we age, these paths may get damaged or broken for various reasons. Because the data is accessible by multiple paths, the brain must try different paths to get at the source. That is what creates the delay. It is working hard to find an alternative path. It may be a smell associated or a color or some other unique attribute.
If brain cells are interconnected with multiple paths, there must also be some mechanism of creating new paths. While some connection may be severed, others may be created as a bypass. The brain is constantly being refereshed, while we sleep. This is when the connections are remade and maintained. As we age, the process slows down and not all the connections are refreshed daily. At some point in time, all the paths are broken and the information is lost forever.
Another sign of old age is forgetting a task at hand. One may decide to cook something on the stove. The door bell ring and you are distracted for a few moment. When one gets back, somehow forgets he was in the middle of cooking something. It gets burnt and only the burning odor becomes a reminder of the task. It is common in old age and we need to set reminders to avoid catastrophe. When I start something on the stove, I set a timer for 15 minutes or some amount and it rings to remind me to check the stove.
How does this happen?
It is part of the failure to multitask. Our brain has the capacity to mutlitask. Two or three tasks can be performed simultaneously. We can talk on the phone and still cook for example. Or we can watch TV while listening to music or a ball game. Our ability to multitask is reduced with old age. The brain needs to do things in sequential order. It is jumping around that causes it to get forgetful.
In terms of our brain activity, what is the mechanism of multitasking?
Is it a serious of instructions like in a computer being processed and when another task is started, an interrupt is created on the execution steps and another set of instructions are processed and then when it is done or on a break, the original task is resumed?
Or is it a true parallel system where two or more tasked are running at the same time and a traffic cop is directing to make sure there is no crosstalk.
In my own experience, it seems it is a combination of both. There are times when I need to do things sequential. When I am focused on a important task, I must do it with undivided attention. However, other times, I can type this article and at the same time listen to a readio broadcast of the news. Somehow, I can do both at the same time.
My conclusion is there are various type of memory. Some are harder to erase. For example, a person who fenced all their adult life have some built in memories of moves. These are almost conditioned and do not require special thought process. When the sign of dementia appears, it is one of the less likely memory to be lost. Why? Because it is almost imprinted and becomes a natural response to a stimulus. It is the same with playing an instrument like the piano. Once a musician practice a piece on a daily basis, he is committing the fingers to a special part of memory. He does not even need to read he music to play. He is almost on auto pilot.
In a similar way, we can do multitasking when part ps of what we do is almost on autopilot.
© 2018 Jack Lee