Amnesia is characterised by memory loss wherein the affected individual finds it challenging to recollect instances from the past or remember new information and facts. Also known as amnestic syndrome, amnesia does not lead to the person completely losing their sense of identity, as they can recall all their personal details, as well as how to carry out normal tasks at home like bathing, cooking, cleaning and while stepping out to work, going for a workout/run, driving a bike/car. It is generally triggered by the deterioration of the memory centres within the brain from stroke, tumours, inflammation, injury or infection.
Types Of Amnesia:
There are many types of amnesia depending upon the extent and kind of memory loss, besides the cause, with the foremost categories being:
In this form of memory loss, events that took place in the recent past and facts learned a short while ago cannot be accurately remembered by the person, but they still recollect their past life as memories generated much earlier are not hampered in the initial stages. Neurodegenerative disorders like dementia trigger retrograde amnesia.
Due to problems in or damage to the hippocampus – the segment of the brain responsible for forming and storing memories, the affected individual cannot create and store new events, facts for retention.
The events occurring in the initial years of life - from the time of birth up until the age of 5 cannot be remembered by adults, as the brain is still developing its functions and neural cognition centres during that phase. This widespread phenomenon is termed childhood amnesia or infantile amnesia.
Amnesia is primarily prompted by damage to the memory portions of the brain, namely the thalamus situated deep in the centre and the hippocampus in the temporal lobe. Various factors induce injury, inflammation and damage to the brain, such as:
- Viral infections like herpes, which instigate encephalitise. inflammation of the brain
- Insufficient oxygen supply to the brain like in a heart attack or lung failure
- Brain tumours arising in memory centres
- Debilitating conditions like Alzheimer’s disease
- Side effects of long-term ingestion of prescription medications for other underlying ailments
- Prolonged and excessive alcohol consumption
- Head injuries from road accidents or playing sports that lead to a concussion
- A stroke or brain aneurysm
- Shock triggered from traumatic experiences in the past
- Having undergone brain surgery or radiation/chemotherapy
The typical signs of amnesia consist of:
- Forgetting instances that took place recently
- Inability to create new memories of events that have just gone by
- Difficulty recollecting past encounters and previously known facts
- A state of confusion and disorientation
- Generation of false memories i.e. confabulation, based on either instances that have already taken place or imaginarily conceived scenarios
The doctor questions the patient about their medical history – such as the kind of memory loss experiences, if they have had any tumours or seizures, face any lack of cognitive skills as well in addition to poor memory of past events and if they consume alcohol often.
Following this, a physical examination to study the neural reflexes and sense of balance in the patient is carried out. Then cognitive tests are conducted, to analyse the patient’s knowledge of current events in the world and facts on general knowledge, such as the existing or previous prime minister’s name or which country won the football world cup etc.
Certain diagnostic assays are also performed to figure out the cause and extent of brain damage. These include blood tests to look for infection, nutritional deficiencies, imaging scans like MRI, CT to visualise any aberrations in the cerebral structures, besides electroencephalogram to gauge if there is any seizure activity.
Treatment for amnesia can help the patient improve their brain-related retention abilities and also focuses on resolving any pre-existing illnesses that trigger memory loss. Occupational therapy sessions teach the affected individual useful techniques and strategies to absorb and store new information, create accurate memories of events in the recent past and enhance the capability to recall past instances as well. It also provides memory training skills that assist the patient in organizing their thoughts and all information they come across and effectively shaping memories in their brain.
In case infection or injury is the cause, then appropriate prescription medications or surgical remedies are recommended, to rectify the condition and hence improve memory. Supplements to resolve nutritional deficiencies are given if any considerable lack of nutrients is detected, which aid in augmenting brain function and memory.