What You Need to Know about Human Memory
When you are asked a question that requires you to relate to an event that occurred a while ago, the moment you open your mouth to recant the said event, you find out that you almost seem to relieve it as you go on. The feelings come rushing back as well as the sounds, the sights, the smells, the feelings and all of the emotions you felt at that particular time become almost instantly fresh again. This phenomenon occurs irrespective of the type of event you are trying to remember, whether pleasurable or traumatic but sometimes more so when it is a traumatic experience. The recalling of the event is a classic case of the memory of the individual at work. Memory is the capacity of the mind to remember and recall some things.
Memory is a very important part of the human personality; humans and their reactions are a function of the memories that we have created. The part of the brain that is responsible for the acquisition storage and retrieval of memory is the temporal lobe. This part of the brain is located lateral to the skull and just above both ears (Gray, Pick & Howden, 1977). This temporal lobe is also responsible for the sense of smell. This is especially significant when you notice that a particular smell/scent almost literally takes you to a different place or reminds you very poignantly about something.
Human memory is divided broadly into short term or temporary memories, long term or permanent memories and working memories. Short term memory is that memory we acquire from viewing or listening to something for a period of time. This kind of memory as remembering the names is held in storage for a very limited amount of time, ranging from a couple of minutes to a few days. The long term memory lasts generally from years to a life time. A memory is formed by the creation of a neurochemical link in the brain which is the basis of a short term memory formation. This memory can be recalled fairly easily for a short while, depending on the importance attached to the memory by the person and the number of and quantity of neurochemical secretions that were released in the process of that situation. These are those chemicals and the feelings that surround the creation of those memories that make some events unforgettable (long term), quickly forgotten (short term) or insignificant. However, some short term memories can become converted to long term memories by the actions of the person with the memory. This could happen by the processing of the memory, for example, by re-reading school notes, recalling and trying to make sense of a conversation, or actively trying to memorize the information either my association or by repetition (Baddley, 2004).
The working memory, however, is a combination of the short and the long term memory; it is an actively updated memory system that we employ in our everyday lives that combine multiple parts of our memory system. It combines or applies the things we already “know” to enable us better appreciate the things right in front of us. For example, mnemonics are an application of facts that we already know, to the memorizing of new information. Another example is driving, if we are driving along a stretch of road it’s our former memories of potholes on that road that determine the course we will take or how fast we will drive on a particular road. We combine the prior information with that which we acquire as we drive and then build a new database of information (Cowan, 2009).
Memory occurs in 3 distinct stages. These stages include the encoding stage, that I earlier stated, the neurochemical connections are formed in the cortex of the brain, and registered in some form, the next stage is the storage stage, this involves the maintenance of the memory or stored information for any amount of time and, finally, the retrieval of the stored information on demand, this is done by recognizing the requisite information and applying it to the task at hand whatever it may be.
Having said this, there are several types of memory that we use consciously or unconsciously in the course of our lives; one of the most commonly used is the sensory memory. This memory is the shortest, it is made up of information derived from all the various kinds of senses that we possess, our ability to recognize a voice, a smell, to tell a nail from a pen just by holding it are applications of our sensory memories. There is the explicit memory which is the one we employ when we answer a question in class, the procedural memory that we employ when we climb on a bicycle and ride of without the need to learn it again. There also is the episodic memory which is the memory that comes into play we are telling the story of a previous experience to our friends. When we use the episodic memory we often use the semantic memory, as well as give chronological order to the sequence of events. There is also the retrospective memory which we employ when we go over events in private. This memory combines all of the before mentioned memory types and is very vital in converting short term memories to long term ones. Finally, there is the prospective memory that essentially remembers the future, this is the memory we use when we make a mental note to do something in the future for example the time of a soccer match or our favorite show or to take out the trash at a particular time in the future (Human Memory, 2010).
Memory plays a huge part in determining our personalities, as we grow up and move from place to place we become who we are and make the choices that we make based on the experiences that we have had. It forms who we are, who we love, who we do not like, the kind of food we eat and those that we do not. This point is made particularly clear in people that have the degenerative condition Alzheimer’s, not only is the memory loss itself distressing, it is the associated information that goes along with the memories that destroys the patient. Because those connections and recognitions effectively define us and when, we have lost those memories, we essentially lose ourselves as well.
When a person has difficultly remembering an event or anything at all we say they simply forgot and a simple prompt will enable them form new associations. We see the light of recognition light up in their eyes and there is the inevitable “ahaa” when they remember. But some peculiar circumstances arise when after some trauma a person is unable to recall any thing that happened; around the time of the trauma, before the trauma or in some special cases after the trauma. In these particular cases the medical term for such forgetfulness is amnesia.
Amnesia could be organic or neurological (post traumatic usually head trauma or iatrogenic) or functional or psychogenic (mental diseases, psychological blocking of a particularly traumatic experience e.g witnessing a homicide). There are generally two types of amnesia: anterograde where the capacity to learn new things is dysfunctional and retrograde where recalling previous events is difficult or impossible. In both cases, especially after trauma, this could be either temporary or permanent.
Our memories define the way we determine our choices and our actions, they are probably the most important part of our personality, and they provide explanation for certain behaviors observed in humans.