Anterograde Amnesia – Short Term Memory Loss

The movies ” Memento”, “So far dates”, “Finding Nemo”, “30 Rock”, Ludachristmas” and recently the Bollywood’s blockbuster hit “Ghajini” personified by Aamir khan prong towards an eminent brain disorder -“Anterograde Amnesia”. Frequently tagged as “Short Term Memory Loss”. The living soul Sanjay Singhania in the Bollywood movie ‘Ghajini’ recollects his bygone memories but is unable to reminisce his present. Such often transpires with some persons who endure this disorder.

Anterograde amnesia or short term memory loss is a predicament that may crop up either through brain injury or by certain drugs in which the individual is gravely enervated in learning new itemized information. Memories or events that happened preceding that injury prevails unscathed but the events that occurred after that injury are lost. Anterograde amnesia is devastating to the person and his family. Person’s adroitness for judgment and intelligence are not hampered.

Learning Afresh

Anterograde amnesics can perform their daily activities and may learn how to ride a bicycle, playing piano. The two elementary forms of memory are declarative memory and procedural memory. Declarative memory is memory for frequently encountered facts. declarative memory is again subdivided into two types: Episodic memory and semantic memory. Episodic memory is recollection of autobiographical facts while semantic memory involves factual information. Procedural memory is memory of schemes of events like how to tie your shoe lace, how to brush your teeth etc. The declarative memory is lost in short term memory loss.

Causes

Short term memory loss can manifest itself in two cases: by drugs of ‘benzodiazepine’ group like midazolam, diazepam etc. or by a traumatic brain injury where hippocampus or surrounding cortices are damaged. Hippocampus is that area of brain through which information is passed before being processed permanently as memory. If hippocampus and medial temporal lobe of brain are vandalized the individual becomes incompetent to process new information however, the older information before that injury remains unviolated. Damage to hippocampus may also be mingled with epilepsy, encephalitis, hypoxia, Alzheimer’s disease. Short term memory loss can also occur by wrecking of the basal fore-brain. Alcoholics can also be afflicted from anterograde amnesia when the BAC reaches above 0.25 percent usually accompanied by hangover.

Reorganization of memory

Persons with anterograde amnesia show varying degree of forgetfulness. When only one side of medial temporal lobe is impaired there is opportunity for normal functioning of memories. Neural Plasticity can be a boon in this regard. remapping can help the patient to recover and become moer skilled at remembering.

famous Cases

The most famous case for anterograde amnesia is that of a patient named Henry Molaison habitually called H.M. In 1957, H.M. under went bilateral lobectomy in which both his medial temporal lobes were exterminated due to which H.M. had bilateral impairment to both hippocampus and perirhinal cortex. He had a conventional IQ, decent vocabulary but was unable to remember new information. Every time he was taught of his mother’s death, due to which he got filled with grief. H.M. remembered all those events that happened before lobectomy. H.M. provided doctors an indication for short term memory loss. H.M. died in 2008 and till that he was used by doctors as an experimental model for understanding anterograde amnesia.

At the moment there is no indemnity for the restoration of anterograde amnesia. It is devastating, dangerous and can transfigure a person’s life to dilapidation. Work on short term memory loss is in ongoing stage we can simply hope that in the near future anterograde amnesia can be antidoted.