Mechanism of Short Term Memory Loss
Short term memory is an integral part of our memory system and is featured by its limited capacity and rapid loss of information. In other words, typically information is stored in short term memory only for a limited time span. Information is retained in the span of short term memory for a very brief period of time instead of crafting neural mechanism for next recalls. On the contrary, long term memory fabricates when information is stored in a neural pathway that can stay there for several hours to the life of the person.
Essentially two reasons have been identified as primary factors contributing short term memory loss. One principle suggests decay results in loss of information, which implies that memories simply become paler over time. Another principle suggests interference is the cause for short term memory loss. There are different theoretical models for suggesting the causes of short term memory loss of which the followings are probably the most familiar.
Baddeley's Working Memory Model
Many scientists and researchers consider short term memory is a dynamic part of the whole memory system and so it is also referred to as working memory. One of the proponents of this hypothesis, A. D. Baddeley identifies working memory into three parts - the visuo-spatial sketchpad, the phonological loop and the central executive.
The visuo-spatial sketchpad regulates the mental imagery segment, whereas the job of central executive is to control the awareness relevant to the information presented. The phonological loop, on the other hand, functions with rehearsal of information in order to keep it in short term memory. As the structure suggests, the information stored on central executive stores for pretty short time, after that new information ‘bumps' the old information and takes its place. Hence, the loss in short term memory occurs.
Brain Function and Short Term Memory Loss
Whenever brain receives new information from sensory input into the regime of short term memory, it produces new neurons in a specific area of hippocampus known as dentate gyrus. This process eliminates old memories in order to construct room for new ones, as argued by researchers. Patients suffering from Alzheimer's disease typically lose cells in the hippocampus area.
One common treatment suggests that the transplantation of stem cells into the affected region in order to substitute the dead cells may offer benefit. However, new studies argue that adding up new cells might not solve the issue rather it will disrupt memory retention by dramatically changing links between neurons in the hippocampus region and enhancing memory clearance.