Memory and Forgetfulness

 Memory is a function of brain by which information is stored in the brain and later recalled to consciousness when required. Memory may be of different types according to the time frame. Such as immediate memory: it functions over a period of seconds;

recent memory: it applies to few minutes to days;

remote memory:  It spans from months to years.  

There is also another elated concept about memory is working memory which consists of recent memory and immediate memory. The smell and emotion may include long-term memories. So scent at times plays a role in controlling the emotions.  

Which part of brain is associated with memory function? 

This has been found after studying patients who have been affected by the brain damage due to infarction or haemorrhage of brain or by tumour or by Alzheimer’s disease etc. Also recently animal studies, and by PET (positron Isotope scan) or MRI contributed information on this subject. 

Three brain structures are important for this function. These are medial temporal lobe, certain nuclei in mid brain, and the basal part of forebrain. The medial temporal lobe which contains hippocampus and amygdala are involved in emotional importance of experience. Some scientists also believe that hippocampus is important for all types of conscious memory, but other claim that it is involved in recollection.

More than fifty years ago a patient known as HM was operated for intractable epilepsy which involved removal of hippocampus and amygdalae on each side of brain. After surgery he lost completely the ability to form and recall memories of facts. Also he was unable to recall events up to eleven years prior.  Still now it is not very clear how the memory is stored in the brain cells. But a lot of chemicals or disease may affect the brain.  

Memory and learning Memory and learning are affected by stress and anxiety. Less amount of anxiety at times helps in learning but when the anxiety and stress becomes overwhelming then it inhibits learning and the memory. In childhood days memory of events from age of three to five years survive, when the child learns to speak. Before that period probably traumatic events associated with smell likely to be remembered. 

What are causes of memory loses 

Memory loss is a common problem in old age, and experience at times makes up that loss. Memory is affected at any age.

The important causes of memory loss are: 

Trauma or injury to head or brain.

After severe head injury surviving patients may have memory problem, in addition to other neurological signs. This head injury may also be chronic as found in boxers due to receiving punches in head for many years.During recovery from acute brain injury the patient may complain of loss of memory previous to the incident (Restrospective memory loss), and the amount of loss depends on the severity of injury and it may take much time to recover. 

Infection of brain by any organism, this may be bacteria, virus, etc. memory loss also found in mad cow disease, AIDS,

Injury to brain by less oxygen supply as happens in heart attacks or when heart suddenly stops.Carbon monoxide gas poisoning also causes brain damage and memory loss.

Degeneration of brain, as found in Alzheimer’s disease, the cause is not known. In degeneration normal brain cells dies and replaced by packing brain cells which has no function in memory. this will be discussed in a different article.

Memory and intelligence are closely associated. When a child is born with low intelligence, it is likely that he or she will have poor memory and learning. Then the child is presented with learning disability. Memory and learning gets affected also in old age or in adults then it is known as dementia. Some of the causes are mentioned above. 

Memory enhancing drugs 

There has been a number of memory enhancing drugs available in the market. These are called “Nootropic” agents. This name is derived from Greek words “noos” means mind and “tropein” means “to bend or trurn”.

Typically nootropic are thought to work by altering the availability of neurochemicals such as neurotransmitters, enzymes, and hormones by improving the brain’s oxygen supply, or by stimulating the nerve growth.In most cases the efficacy of them has not been conclusively proved.    

The some important nootropic agents are Piracetam the most commonly taken and first developed and then others also in the market become available such as Pramiracetam, Oxiracetam, and Aniracetam. They act on the brain neurotransmitters such as acetylcholine and glutamate. There has been no report of severe side effects from these medications.The other memory enhancers are Hydergine, Vinpocetine etc. 

A lot of brain stimulating agents are used to increase the productivity. They improve the attention and concentration thus increasing the memory performance. The drugs are: Amphetamine, Methamphetamine, Cocaine, Methylphenidate, Pemolin etc. These drugs increase alertness thus helping to enhance the cognition. But if those are taken on a regular basis it may cause intense anxiety, tension and paranoid ideas and precipitate psychosis. Those drugs also increase blood pressure, cause insomnia. These are not used as memory enhancers as due to abuse potentiality.  

The medications such as Modafinil, Armodafinil and Adrafinil also enhance alertness and thus increase functioning in persons suffering from sleep disorders such as narcolepsy. These medications are not used as memory enhancers. These medications have abuse potentiality and so should not be used without medical supervision.

The commonest used memory enhancers or performance enhancers are caffeine and theophyline found in tea and coffee. It helps in reduce fatigue thus improve attention and concentration.

Is memory can be enhanced?

There have been a lot of medicines available the drug companies claim that helps in improving memory. Some claims are related to improvement of dementia, though the results at times are conflicting. There are a number of traditional medicines or herbs claimed to be helpful in improving memory.

The following may be important, the results are not consistent and at times it is not noticeable or slow to evolve.

1)     Regular intake of Omega-3 fatty acids, this helps stimulate brain activity, increase memory and mental awareness. The good natural source of Omega -3 fatty acid id from nuts, fish, seafood, and flaxseed.

2)     Ginko biloba is one of the most natural herbs to prevent loss of memory. It improves blood circulation in the brain and it contains antioxidant that reduces the harmful free radicals, thus protecting the nerve cells.

3)     Rosemary (Rosmarinus officinalis), a herb in cooking also improve memory and increase concentration. Rosemary contains two important ingredients such as caffeic acid and rosemarinic acid which are responsible for it’s therapeutic actions. Both ingredients are antioxidant and anti-inflammatory.  It is also a rich source of vitamin E (alpha tocopherol), another potent antioxidant. Rosemary provides an important defence against cancer, it blocks oestrogen , so prevents breast cancer, also minimise the effects of aging of skin.

4)     Memory can be boosted by antioxidants supplements such as Vitamin E and Vitamin C. Studies have shown that regular intake of vitamin E and C helps prevent memory loss, increase cognitive functions such as attention, concentration, protect brain from minor strokes which cause dementia. It also reduces the risk of Alzheimer’s disease.

Forgetfulness

Many older and younger people also worry about becoming forgetful. They think forgetfulness is the first sign of dementia or Alzheimer’s disease. In the past, loss of memory and confusion were thought to be normal part of aging. However now scientists know that most people remain both alert and able as they grow old, but they may take longer time to remember things. A lot of people experience memory problems, some are serious and others are not. So people who have serious changes in memory, behaviour and personality may suffer from dementia. It also affects person’s ability to perform day to day activities. Alzheimer’s disease is one kind of dementia.

Dementia is characterized by the following symptoms, and these are the result of changes in the brain:

1)     Becoming lost in familiar place

2)     Unable to follow directions

3)     Asking same questions many times

 4)     Not able to remember time, place or person

5)     Neglecting personal hygiene, safety and nutrition.

6)     Not able or delay in learning new things or information. 

People lose their memory at different rates and sometimes older people with depression may present with poor attention, concentration, low mood, poor memory and at times gets confused and this may look very like dementia.

Dementia like features are also found in patients having head injury, particularly for elderly people who forgets about head injury or minor fall.

Elderly patients taking sleep medications also can produce features of dementia. Side effects of some medications may mimic dementia.

Even dehydration or loss of water and salt from body due to hot weather, or diarrhea or less intake of water may cause dementia like symptoms.

Malnutrition and vitamin deficiency also cause dementia like features in chronic alcoholics.

Stroke is another important cause of dementia, and this is associated with other neurological signs and symptoms.  

Understanding memory loss:

What is normal and what is not.

Memory loss is common when people grow old and it is progressive at times. People may forget newly learned names or tasks and they may take more time to learn. They may admit it openly about it, and struggle to improve it usually does not help. Usually this kind of normal rate of memory loss can be managed by the following activities to improve the living situation:

Ø      Try to learn a new skill though it takes more time than usual.

Ø      Do some volunteer activity or do some regular activity at home

Ø      Do not isolate self and try to spend more time with family and friends

Ø      Use memory tools, such a big calendars, to do list or notes

Ø      Keep your keys, glasses, wallet at a fixed place.

Ø      Take enough rest and avoid any kind of overwork.

Ø      Do not use alcohol to deal with any kind of stress.

Ø      If your mood is low for few weeks or so then talk to a doctor for help.

When a person was functioning normally at home but becomes disoriented or lost in a new environment as happens in vacation then it signifies a severe problem with memory and needs professional assessment and management. 

Some treatable memory problems:

Depression: Elderly persons at times presents with memory problem when they are depressed. If depression is treated adequately then dementia like features also improves.

Nutritional deficiency: Malnutrition at times leads to vitamin and mineral deficiency, thus causing dementia like symptoms, can be corrected by adequate healthy food. Dehydration and electrolyte imbalances also cause dementia like features. This is common in poor homeless people or single person, unemployed, in low socioeconomic condition, having no social support or at times also found in rest homes.

Thyroid deficiency: Also cause dementia and memory problems.

Head injury: elderly persons often forget about minor head injury or fall, which can contribute confusion and memory problem. So somebody who was functioning quite well and suddenly presents with memory problem and confusion then head injury must be excluded.

Side effects of some medications such as sedatives and hypnotics, thus causing confusion, poor attention, concentration affecting memory and mimic like dementia. 

 How to prevent or slow down memory loss

This is a lengthy and continuous process and it should be started before a person becomes old. One needs to do some mental exercise, as we need to physical exercise daily. The usual mental exercises are solving cross-word puzzle, or any puzzle, such as Sudoku, play cards etc. Socialize as much as possible, and do some physical exercise, even few kilometers of walking every alternate day would be enough.

Retired life means not to retire from all the activities, only from usual job, but at times part time jobs, voluntary or paid would help to keep mind active. Avoidance of alcohol also important in this regard.It has been found that those who continue to work longer years their memory tend to remain unaffected for longer time.