People suffering from memory loss display forgetfulness. They commonly have an inability to learn new information and this is called short-term memory impairment. They appear confused as they may be disorientated regarding their current time and place. It is unusual for people with amnesia to forget old or well-learned memories.
Milder forms of forgetfulness in adults are characterised by no clear pattern of memory impairment. People forget short-term or long-term information, and may even forget over-learned information such as an ATM PIN code, while at the same time remember information well that has been learned recently. This type of forgetfulness often occurs together with depression, anxiety and stress.
Memory impairment is an inability to remember information to the extent that a person has difficulty adjusting to the demands of life. Thus, performance in social- and occupational roles is impaired.
Amnesia, impaired memory, forgetfulness, loss of memory, a total blank
The causes of memory loss differ for younger versus older adults. The term older adults refers to people older than 65 years. The list below provides the more common causes first followed by rare conditions.
Memory loss in younger adults:
- Anxiety and stress can cause memory problems. A feeling of tension and inability to relax often results in deficient concentration that causes incomplete information to filter through to the brain's memory engines. The partial information results in the formation of incomplete memories with resultant amnesia.
- Depression also causes a lack of attention and focus, leading to problems of recall and memory. Lack of energy and motivation also affects your ability to form good quality memories. Treating the depression improves mood and most often also the associated memory deficits.
- Sleep disturbances such as insomnia or sleep apnoea, which affect the quality or quantity of sleep one gets, can also affect memory.
- Excessive use of tranquilliser drugs harms memory as they work by suppressing brain functioning. This also affects the function of the memory engines leading to forgetfulness.
- Hypothyroidism, or in other words an under-active thyroid, cause a decrease of brain cell productivity and consequently problems with remembering recent events.
- Traumatic brain injury leading to unconsciousness causes memory loss. Injury to the memory engines themselves leads to forgetfulness, which may be enduring.
- Alcohol and illicit drug dependency can change chemicals in the brain, which in turn will affect memory. Heavy alcohol use can cause a deficiency in vitamin B1, which interferes with memory.
- Anaemia, where red blood cell capacity for carrying oxygen is reduced, can result in weakness, tiredness and fatigue. This may lead to confusion and memory loss.
- Strokes, which are characterised by a loss of brain function due to a blood flow problem, can cause a number of memory problems. These include learning and remembering new information; applying known information in different settings; doing everyday things without being prompted; getting confused or lost in familiar places and losing track of the day or time.
- Multiple sclerosis (MS) results from damage to myelin, a protective sheath surrounding nerve fibres of the central nervous system. This damage interferes with messages been sent from the brain to other parts of the body. As MS changes parts of the brain and spinal cord, sufferers sometimes experience problems with thinking and memory.
- Infections of the brain. A large number of micro-organisms (germs) could infect the brain, spinal cord and surrounding parts. Although viruses and bacteria are the most common, it is also possible for fungi, parasites and others to infect the brain. Disease names depend on the location of the infection, for example meningitis (inflammation of the meninges, that is membranes of brain, spinal cord, and fluids), encephalitis (brain) and myelitis (spinal cord).
Memory loss in older adults:
- Alzheimer's disease. This condition affects primarily short-term memory in the early stages of the illness. The disease progresses and affects other aspects of brain function, resulting in eventual brain failure. The illness is caused by the formation of abnormal proteins (amyloid) that damages brain cells.
- Vascular dementia is also a condition of brain failure, but starts with impairment of planning abilities before progressing to other aspects of brain functioning. Hardening of the arteries (atherosclerosis) is the cause.
- Depression, see above.
- Dehydration, that is not having enough fluids in your body, can lead to confusion and memory problems.
- Side-effects of prescription and other drugs, as they may change brain chemicals that are important for memory and thinking.
- Hypo- or hyperthyroidism. Thyroid dysfunctions can lead to problems with remembering recent events.
- Traumatic brain injury also occurs in older adults, often as a results of falls.
- Minor head injuries
- Brain tumours press on brain structures to disrupt memory structures.
- Other progressive brain conditions such as Lewy body disease, Parkinson's disease, and so forth also affect memory functions in older adults.
- Regular exercise and good nutrition are the cornerstones of good memory. It is especially important for older adults to continue to exercise and eat healthy as they age.
- There are numerous compensation strategies to help improve functioning for individuals with forgetfulness. These include common strategies that most healthy people use such as diaries, notepads and electronic diaries. Amnesiics may forget to use these tools and thus have to use special reminders such as regular daily alarms.
- There are also a variety of tricks to improve memory. Visualisation is one such an approach - it involves forming pictures of the material that has to be remembered. These pictures can be linked with a story to facilitate recall.
- In more severe cases of memory impairment, such as in Alzheimer's disease, it is useful to re-orientate patients with calendars, familiar objects, photos or music.
- Some experts have shown that it might be beneficial for individuals with Alzheimer's disease who are also receiving medical care to take ginkgo biloba. Other homeopathic treatments have not shown benefits in controlled studies.
When to see a doctor
It is normal to occasionally forget things such as where you left your car keys or why you walked into the kitchen only to wonder why you are there as you enter the room. With ageing it is also normal to get more forgetful; take a little bit longer to learn new things, to remember familiar names and words or to find your glasses. However, you should consult your GP if you experience memory loss that interferes with your ability to function normally in day-to-day activities. Examples of normal functioning include driving a car, shopping, handling money or balancing a cheque book. Other signs of possible serious memory problems are getting lost in well-known places; forgetting the way home; not being able to follow directions; frequently asking the same questions over and over; being very confused about time, people and places; and not keeping up with personal hygiene or looking after yourself (such as eating or being safe in the home).
What to expect at the doctor
Your GP will take a medical history and perform a thorough physical examination. Family and friends may be questioned as patients may forget important aspects of their history. A short screening test for memory, such as the Mini-Mental Status Examination test (www.gomemory.co.za/MMSE.html), is usually performed.
The following questions may be asked:
"When did your forgetfulness start?"
"Is it stable or progressive?"
"Describe the type of information that you forget?"
"How does your forgetfulness impact on your lifestyle?"
Screening blood tests to exclude common conditions such as thyroid dysfunction and anaemia may be done.
A psychologist using neuropsychological tests will do a further and more detailed assessment of memory impairment.
Unexplained memory impairment may be further investigated by neuroimaging such as CT or MRI scanning.
The underlying condition causing the amnesia will be treated first.
Occupational therapists specialise in using compensation strategies to improve memory and this field is called cognitive rehabilitation.
Memory enhancers are available for Alzheimer's disease and these treatments may also delay progression of the illness.