What is memory loss?
Memory loss, also known as amnesia or amnestic syndrome, refers to an unusual degree of forgetfulness and/or loss of ability to recall past events, facts and information.
What are the causes of the disorder?
For normal memory in a person, different parts of a brain are involved. Amnesia that results from an injury or disease to a part of the brain that interferes with memory is known as organic or neurological amnesia. This form of amnesia may be caused by:
- Encephalitis (brain inflammation) due to a viral infection or autoimmune reaction to cancer
- Long-term abuse of alcohol resulting in thiamine (vitamin B1) deficiency
- Degenerative brain diseases like Alzheimer’s disease or dementia
- Brain tumours in areas that control memory
- Lack of adequate oxygen in brain resulting from a heart attack, carbon monoxide poisoning or respiratory distress
- Electroconvulsive therapy
- Certain medicines like benzodiazepenes
Another type of amnesia is called psychogenic or dissociative amnesia. It results from trauma or emotional shock, like during an accident or as a victim of a violent crime. The person loses personal memories for a brief period.
What one needs to know about symptoms or signs?
Amnesia is presented in the following forms:
- Transient global amnesia – Rare, temporary, complete loss of memory.
- Anterograde amnesia – Inability to recall recent events, post a traumatic experience.
- Retrograde amnesia – Inability to remember experiences prior to a trauma, but able to recall events afterward.
Most patients of amnesia have problems with their short-term memory, i.e. they are unable to retain new information. While more remote, deeply ingrained memories are intact, recent memories are more likely to be lost. For example, a patient may be able to recall a childhood memory but will find it difficult to recall the current month. A case of isolated memory loss does not affect a person’s intelligence, awareness, attention span, judgement or personality, and people with amnesia are able to understand written and spoken words and learn new skills. They may also be able to comprehend that they have a memory disorder.
Dementia and memory loss
Dementia refers to a set of symptoms that includes impairment of memory, reasoning, judgement, language and thinking skills. Though memory loss is among the first recognisable signs of dementia, amnesia is not the same as dementia. Dementia also involves other cognitive problems along with memory loss. Depending on the cause of amnesia, other signs and symptoms may include:
- False or invented recollections or genuine memories misplaced in time
- Neurological issues like tremors, seizures and uncoordinated movements
- Disorientation and confusion
Which specialist should be consulted in case of signs and symptoms?
A person suspecting memory loss must consult a general practitioner who would then refer the patient to a neurologist, a doctor who specialises in disorders of the brain and nervous system.
What are the screening tests and investigations done to confirm or rule out the disorder?
A doctor will carry out extensive evaluation to rule out other causes of memory loss like Alzheimer’s disease, dementia or brain tumour. Tests include:
- Medical history – The patient, a family member or a friend can provide details of the patient’s medical records to understand the loss of memory.
- Physical examination – A physical exam includes a neurological test to check reflexes, balance, sensory function and other physiological aspects of the nervous system and brain.
- Cognitive testing – The patient’s judgement, thinking and memory (both short-term and long-term) are tested to determine the extent of memory loss and ascertain what kind of help the person may need.
- Imaging tests – The doctor may check for abnormalities in the brain through certain imaging tests like the magnetic resonance imaging (MRI), computed tomography (CT) scan and encephalopathy.
What treatment modalities are available for management of the disorder?
Treatment for amnesia depends on strategies and techniques to compensate for the memory problem. These include:
- Occupational therapy – An occupational therapist can help a patient learn new information to replace the lost one, or use intact memories to take in new ones. Memory training strategies help organise information that allow a patient to remember more easily and improve their understanding.
- Medication and supplements – There are no medications currently available to treat most types of amnesia. However, the Wernicke-Korsakoff syndrome, which involves a deficiency of vitamin B1 can be treated by supplementing the vitamin and taking proper nutrition. Alcohol abstinence can prevent further damage.
- Use of technology – Digital devises and electronic organisers can help a patient keep up with daily tasks through reminders for crucial events or medications. Other devices that may be used are low-tech memory aids like notebook, wall calendars and photographs of people and places.
What are the known complications in management of the disorder?
The severity and scope of amnesia varies in different patient, but it can take a toll on the quality of life even in its mildest form. Patients may face difficulties at work, school or social settings. Some patients may even need to stay in an extended care facility or under supervision of a caretaker. It sometimes may not be possible to recover lost memories.
How can the disorder be prevented from happening or recurring?
Brain damage is an important cause of amnesia, and therefore, it is important to minimise the chances of a brain injury through
- Avoiding excess alcohol
- Treating infections in a timely manner before they reach the brain
- Wearing seat belt or helmet when driving or cycling
- Seeking immediate help in case of stroke or brain aneurysm. Symptoms include severe headache or one-sided numbness or paralysis.
It can be useful to sharpen memory by staying mentally active, interacting socially to keep off depression and stress, staying organised and avoiding clutter, and sleeping well to help consolidate memories.
How can a caregiver give support and help the patient cope with the disorder?
It can be a tough experience for the patient to deal with memory loss. Patients with very severe forms of amnesia may need direct assistance from family members, friends or professional health care providers.
Image courtesy of [Victor Habbick] / FreeDigitalPhotos.net Sources: “Amnesia,” MayoClinic.com, Mayo Clinic Staff, http://www.mayoclinic.org/diseases-conditions/amnesia/basics/definition/con-20033182 “Dementia,” MayoClinic.com, Mayo Clinic Staff, http://www.mayoclinic.org/diseases-conditions/dementia/basics/definition/con-20034399 “Memory loss: When to seek help,” MayoClinic.com, Mayo Clinic Staff, http://www.mayoclinic.org/diseases-conditions/alzheimers-disease/in-depth/memory-loss/art-20046326 “Memory loss: 7 tips to improve your memory,” MayoClinic.com, Mayo Clinic Staff, http://www.mayoclinic.org/healthy-living/healthy-aging/in-depth/memory-loss/art-20046518 “Memory Loss,” WebMD.com, http://www.webmd.com/brain/memory-loss “Memory Loss,” MedicineNet.com, Melissa Conrad Stöppler, MD, http://www.medicinenet.com/memory_loss/symptoms.htm “Memory Loss,” medlinePlus, NLM,NIH, http://www.nlm.nih.gov/medlineplus/ency/article/003257.htm