Oh! I forgot to send this letter to my head office".   "Please don't forget to contact me next week".  "I could not recollect this particular formula to solve the problem last week".  "I will remember the services offered by you".  Such are the common words and experiences we encounter in our day to day life.   We remember and forget things. It is a wonder to see how this complex process of memory and forgetting goes in small human brain which approximately consists of 10 - 12 billion active nerve cells.  In human brain about 100 billion neurons pass  signals to each other via as many as 1,000 trillion synaptic connections. It continuously receives and analyzes sensory information, responding by controlling all bodily actions and functions. It is also the centre of higher-order thinking, learning and memory, and gives us the power to think, plan, speak, imagine, dream, reason and experience emotions.
Memory implies the ability to retain the information in the human brain and regain as and when necessary.  Human memory is  like memory in a computer, allows us to store information for later use.   The limbic system, which includes the hippocampus, the amygdala, the cingulate gyrus, the thalamus, the hypothalamus, the epithalamus, the mammillary body and other organs, many of which are of particular relevance to the processing of memory.   Hippocampus,  is essential for memory function, particularly the transference from ‘short term’ to ‘long term’ memory and control of spatial memory.  This storage of information is largely time dependent, although, certain exceptions exist. There is no doubt that this storage is not a dump of facts and events. It appears that human memory has some sort of organization. Otherwise it is impossible for us to construct and reason out things with correlation.   Memory can be treated as three stage system - encoding, storage and retrieving. 'Encoding' means transformation of sensory information into a form that can be processed by a memory system. 'Storage' is preserved. The 'Retrieval' process refers to a mechanism by which the encoded information is located and recalled.  Psychologists argue that memory mechanism is organized on two step processes. These are Short Term Memory (STM) and Long Term Memory (LTM).  The STM is a rapidly falling mechanism. This means that, information entering STM decays quickly, unless rehearsed frequently. Such rehearsal transfers information to a rehearsal buffer.  LTM is, on the other hand a relatively permanent storage of information in the brain. It can be recalled again and again. It is a clear fact to note that any incoming information first enters STM. Due to repeated rehearsals it enters into rehearsal buffer and finally into LTM.  Although we have permanently stored information in LTM. We fail to retrieve, sometimes, from thinking process. This is mainly due to the fact that the cues needed to retrieve information from LMT are incomplete. Such experiences are common in out day to day experiences as trying to retrieve a telephone number or an address of a friend. Such phenomenon is called as Tip of the Tonque (TOT).    When we fail to recollect something, this amounts to forgetting. Failing to remember   doesn’t mean the information is gone forever.This may be either due to failure of retrieval mechanism to draw information from LTM or the necessary information must have decayed due to improper input.  If the necessary information of idea is not used for longer period, the information fades away from memory.  Sometimes forgetting may result in due to interference of some fresh information pouring into the brain. Thus newly learned information may superpose over the old information leading to masking.  	 The process of 'forgetting' might result in some cases due to 'repression' a phenomenon, by which information is forcible forgotten, possibly because of retrieval of such information in some way or other is unacceptable to the person, possibly leading to feelings such as anxiety, guilt, etc..  Injuries to brain cells, drug effects and similar physiological factors may also result in loss of memory permanently.
Memories are not stored in our brains like books on library shelves, but are actively reconstructed from elements scattered throughout various areas of the brain by the encoding process
Sensory memory is an ultra- short-term memory and decays or degrades very quickly, typically in the region of 200 - 500 milliseconds
Memory   &   Forgetting
Iconic Memory: Sensory memory Echoic memory: Aural stimuli memory Haptic memory: Touch memory Olfactory memory: memory of smell
Health Scan March 2019 www.healthscan.biz
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