Memory loss

Memory loss also known as amnesia means unusual forgetfulness. When you have memory loss, you may not be able to remember new events, recall one or more memories of your past, or both. Memory loss may be for a short time and then resolve (temporary). Or, your memory loss may not go away and, depending on the cause, it can get worse over time.

Some memory loss is a natural part of aging and it remains one of the biggest concerns for older patients. Many people worry about becoming forgetful. They think forgetfulness is the first sign of Alzheimer’s disease. But not all people with memory problems have Alzheimer’s disease. Various medical conditions have been associated with memory loss, including dementia, transient global amnesia, other neurologic disorders, mild cognitive impairment, head trauma, alcohol and medication use, thyroid-related issues, mental illnesses, emotional problems and other medical conditions.

Forgetfulness can be a normal part of aging. As people get older, changes occur in all parts of the body, including the brain. As a result, some people may notice that it takes longer to learn new things, they don’t remember information as well as they did, or they lose things like their glasses. These usually are signs of mild forgetfulness, not serious memory problems, like Alzheimer’s disease.

Table 1. Differences between normal aging and Alzheimer’s disease

What’s normal memory loss and what’s not?

What’s the difference between normal, age-related forgetfulness and a serious memory problem? Serious memory problems make it hard to do everyday things like driving and shopping. Signs may include:

• Asking the same questions over and over again
• Getting lost in familiar places
• Not being able to follow instructions
• Becoming confused about time, people, and places

Memory loss causes

It is normal to have some trouble learning new material or needing more time to remember it. But normal aging does not lead to dramatic memory loss. Such memory loss is due to other diseases.

Memory loss can be caused by many things. To determine a cause, your health care provider will ask if the problem came on suddenly or slowly.

Many areas of the brain help you create and retrieve memories. A problem in any of these areas can lead to memory loss.

Memory loss may result from a new injury to the brain, which is caused by or is present after:

• Brain tumor
• Blood clots in the brain
• Infections in the brain
• Cancer treatment, such as brain radiation, bone marrow transplant, or chemotherapy
• Concussion or head trauma from a fall or accident
• Not enough oxygen getting to the brain when your heart or breathing is stopped for too long
• Severe brain infection or infection around brain
• Major surgery or severe illness, including brain surgery
• Transient global amnesia (sudden, temporary loss of memory) of unclear cause
• Transient ischemic attack (TIA) or stroke
• Hydrocephalus (fluid collection in the brain)

Sometimes, memory loss occurs with mental health problems, such as:

• After a major, traumatic or stressful event
• Bipolar disorder
• Depression or other mental health disorders, such as schizophrenia

Memory loss may be a sign of dementia. Dementia also affects thinking, language, judgment, and behavior. Common types of dementia associated with memory loss are:

• Alzheimer disease
• Lewy body dementia
• Fronto-temporal dementia
• Progressive supranuclear palsy
• Normal pressure hydrocephalus
• Creutzfeldt-Jakob disease (mad cow disease)

Other causes of memory loss include:

• Drinking too much alcohol or use of prescription or illegal drugs
• Brain infections such as Lyme disease, syphilis, or HIV/AIDS
• Overuse of medicines, such as barbiturates or (hypnotics)
• ECT (electroconvulsive therapy) (most often short-term memory loss)
• Epilepsy that is not well controlled
• Illness that results in the loss of, or damage to brain tissue or nerve cells, such as Parkinson disease, Huntington disease, or multiple sclerosis
• Low levels of important nutrients or vitamins, such as low vitamin B1 or B12
• Some thyroid, kidney, or liver disorders
• Not eating enough healthy foods, or too few vitamins and minerals in a person’s body

Memory loss related to emotional problems

Emotional problems, such as stress, anxiety, or depression, can make a person more forgetful and can be mistaken for dementia. For instance, someone who has recently retired or who is coping with the death of a spouse, relative, or friend may feel sad, lonely, worried, or bored. Trying to deal with these life changes leaves some people feeling confused or forgetful.

The confusion and forgetfulness caused by emotions usually are temporary and go away when the feelings fade. Emotional problems can be eased by supportive friends and family, but if these feelings last for more than 2 weeks, it is important to get help from a doctor or counselor. Treatment may include counseling, medication, or both. Being active and learning new skills can also help a person feel better and improve his or her memory.

Mild cognitive impairment

Some older adults have a condition called mild cognitive impairment, or mild cognitive impairment, in which they have more memory or other thinking problems than other people their age. People with mild cognitive impairment can take care of themselves and do their normal activities. mild cognitive impairment may be an early sign of Alzheimer’s, but not everyone with mild cognitive impairment will develop Alzheimer’s disease.

Signs of mild cognitive impairment include:

• Losing things often
• Forgetting to go to important events or appointments
• Having more trouble coming up with desired words than other people of the same age

If you have mild cognitive impairment, visit your doctor every 6 to 12 months to see if you have any changes in memory and other thinking skills over time. There may be things you can do to maintain your memory and mental skills. No medications have been approved to treat mild cognitive impairment.

Dementia

Dementia is not a disease itself but rather an umbrella term used to describe a set of symptoms that result from damage to the brain caused by different diseases.

Diseases that cause progressive damage to the brain  and consequently result in dementia include:

• Alzheimer’s disease, the most common cause of dementia
• Vascular dementia
• Frontotemporal dementia
• Lewy body dementia

There are different forms of dementia. Alzheimer’s disease is the most common form in people over age 65.

The disease process (pathology) of each of these conditions differs somewhat. Memory impairment isn’t always the first sign, and the type of memory problems varies. It’s also possible to have more than one type of dementia, known as mixed dementia.

Dementia is the loss of cognitive functioning such as thinking, remembering, learning and reasoning and behavioral abilities to such an extent that it interferes with daily life and activities. Memory loss, though common, is not the only sign. A person may also have problems with language skills, visual perception, or paying attention. Some people have personality changes. Dementia is not a normal part of aging.

Dementia usually begins gradually, worsens over time and impairs a person’s abilities in work, social interactions and relationships.

Dementia is not a natural part of ageing. This is why it’s important to talk to your doctor sooner rather than later if you’re at all worried about memory problems or other symptoms.

Common early symptoms of dementia

Different types of dementia can affect people differently, and everyone will experience symptoms in their own way.

However, there are some common early symptoms that may appear some time before a diagnosis of dementia. These include:

• memory loss
• difficulty concentrating
• finding it hard to carry out familiar daily tasks, such as getting confused over the correct change when shopping
• struggling to follow a conversation or find the right word
• being confused about time and place
• mood changes

These symptoms are often mild and may get worse only very gradually. It’s often termed “mild cognitive impairment” (mild cognitive impairment) as the symptoms are not severe enough to be diagnosed as dementia.

You might not notice these symptoms if you have them, and family and friends may not notice or take them seriously for some time. In some people, these symptoms will remain the same and not worsen. But some people with mild cognitive impairment will go on to develop dementia.

Other early signs of dementia might include:

• Asking the same questions repeatedly
• Forgetting common words when speaking
• Mixing words up — saying “bed” instead of “table,” for example
• Taking longer to complete familiar tasks, such as following a recipe
• Misplacing items in inappropriate places, such as putting a wallet in a kitchen drawer
• Getting lost while walking or driving in a familiar area
• Having changes in mood or behavior for no apparent reason

Alzheimer’s disease

Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks. In most people with the disease—those with the late-onset type—symptoms first appear in their mid-60s. Early-onset Alzheimer’s occurs between a person’s 30s and mid-60s and is very rare. Alzheimer’s disease is the most common cause of dementia among older adults.

Memory problems are typically one of the first signs of Alzheimer’s, though initial symptoms may vary from person to person. A decline in other aspects of thinking, such as finding the right words, vision/spatial issues, and impaired reasoning or judgment, may also signal the very early stages of Alzheimer’s disease. Mild cognitive impairment is a condition that can be an early sign of Alzheimer’s disease, but not everyone with mild cognitive impairment will develop the disease.

People with Alzheimer’s disease have trouble doing everyday things like driving a car, cooking a meal, or paying bills. They may ask the same questions over and over, get lost easily, lose things or put them in odd places, and find even simple things confusing. As the disease progresses, some people become worried, angry, or violent.

Symptoms specific to Alzheimer’s disease

The most common cause of dementia is Alzheimer’s disease. Common symptoms of Alzheimer’s disease include:

• memory problems – regularly forgetting recent events, names and faces
• asking questions repetitively
• increasing difficulties with tasks and activities that require organisation and planning
• becoming confused in unfamiliar environments
• difficulty finding the right words
• difficulty with numbers and/or handling money in shops
• becoming more withdrawn or anxious

Alzheimer’s disease is named after Dr. Alois Alzheimer. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps (now called amyloid plaques) and tangled bundles of fibers (now called neurofibrillary, or tau, tangles).

These plaques and tangles in the brain are still considered some of the main features of Alzheimer’s disease. Another feature is the loss of connections between nerve cells (neurons) in the brain. Neurons transmit messages between different parts of the brain, and from the brain to muscles and organs in the body. Many other complex brain changes are thought to play a role in Alzheimer’s, too.

This damage initially appears to take place in the hippocampus, the part of the brain essential in forming memories. As neurons die, additional parts of the brain are affected. By the final stage of Alzheimer’s, damage is widespread, and brain tissue has shrunk significantly.

Alzheimer’s disease is currently ranked as the sixth leading cause of death in the United States, but recent estimates indicate that Alzheimer’s disease may rank third, just behind heart disease and cancer, as a cause of death for older people. The time from diagnosis to death varies—as little as 3 or 4 years if the person is older than 80 when diagnosed, to as long as 10 or more years if the person is younger.

Memory loss diagnosis

Your doctor will perform a physical exam and ask about your medical history and symptoms. This will usually include asking questions from your family members and friends. For this reason, they should come to the appointment.

Medical history questions may include:

• Type of memory loss, such as short-term or long-term
• Time pattern, such as how long the memory loss has lasted or whether it comes and goes
• Things that triggered memory loss, such as head injury or surgery

Tests that may be done include:

• Blood tests for specific diseases that are suspected (such as low vitamin B12 or thyroid disease)
• Cerebral angiography
• Cognitive tests (neuropsychological/psychometric tests)
• CT scan or MRI of the head
• Electroencephalogram (EEG)
• Lumbar puncture

You might be referred to a specialist in diagnosing dementia or memory disorders, such as a neurologist, psychiatrist, psychologist or geriatrician.

Memory loss treatment

Finding the cause of the memory impairment is important to determine the best course of action. Memory loss treatment depends on the cause of memory loss. Your doctor can tell you more.

Memory loss and other thinking problems have many possible causes, including depression, an infection, or a medication side effect. Sometimes, the problem can be treated, and the thinking problems disappear. Other times, the problem is a brain disorder, such as Alzheimer’s disease, which cannot be reversed.

Some people are tempted by untried or unproven “cures” that claim to make the brain sharper or prevent dementia. Check with your doctor before trying pills, supplements or other products that promise to improve memory or prevent brain disorders. These “treatments” might be unsafe, a waste of money, or both. They might even interfere with other medical treatments. Currently there is no drug or treatment that prevents Alzheimer’s disease or other dementias.

A person with memory loss needs a lot of support.

• It helps to show the person familiar objects, music, or and photos or play familiar music.
• Write down when the person should take any medicine or do other important tasks. It is important to write it down.
• If a person needs help with everyday tasks, or if safety or nutrition is a concern, you may want to consider extended-care facilities, such as a nursing home.

Tips for dealing with memory loss or forgetfulness

People with some forgetfulness can use a variety of techniques that may help them stay healthy and deal with changes in their memory and mental skills. Here are some tips:

• Learn a new skill.
• Stay involved in activities that can help both the mind and body.
• Volunteer in your community, at a school, or at your place of worship.
• Spend time with friends and family.
• Use memory tools such as big calendars, to-do lists, and notes to yourself.
• Put your wallet or purse, keys, and glasses in the same place each day.
• Get lots of rest.
• Exercise and eat well.
• Don’t drink a lot of alcohol.
• Get help if you feel depressed for weeks at a time.

Tips to improve your memory

Although there are no guarantees when it comes to preventing memory loss or dementia, certain activities might help. Consider seven simple ways to sharpen your memory — and know when to seek help for memory loss.

1. Include physical activity in your daily routine

Physical activity increases blood flow to your whole body, including your brain. This might help keep your memory sharp.

For most healthy adults, the Department of Health and Human Services recommends at least 150 minutes a week of moderate aerobic activity, such as brisk walking, or 75 minutes a week of vigorous aerobic activity, such as jogging — preferably spread throughout the week. If you don’t have time for a full workout, squeeze in a few 10-minute walks throughout the day.

2. Stay mentally active

Just as physical activity helps keep your body in shape, mentally stimulating activities help keep your brain in shape — and might keep memory loss at bay. Do crossword puzzles. Play bridge. Take alternate routes when driving. Learn to play a musical instrument. Volunteer at a local school or community organization.

3. Socialize regularly

Social interaction helps ward off depression and stress, both of which can contribute to memory loss. Look for opportunities to get together with loved ones, friends and others — especially if you live alone.

4. Get organized

You’re more likely to forget things if your home is cluttered and your notes are in disarray. Jot down tasks, appointments and other events in a special notebook, calendar or electronic planner.

You might even repeat each entry out loud as you jot it down to help cement it in your memory. Keep to-do lists current and check off items you’ve completed. Set aside a place for your wallet, keys, glasses and other essentials.

Limit distractions and don’t do too many things at once. If you focus on the information that you’re trying to retain, you’re more likely to recall it later. It might also help to connect what you’re trying to retain to a favorite song or another familiar concept.

5. Sleep well

Sleep plays an important role in helping you consolidate your memories, so you can recall them down the road. Make getting enough sleep a priority. Most adults need seven to nine hours of sleep a day.

6. Eat a healthy diet

A healthy diet might be as good for your brain as it is for your heart. Eat fruits, vegetables and whole grains. Choose low-fat protein sources, such as fish, beans and skinless poultry. What you drink counts, too. Too much alcohol can lead to confusion and memory loss. So can drug use.

7. Manage chronic conditions

Follow your doctor’s treatment recommendations for medical conditions, such as depression, high blood pressure, high cholesterol, diabetes, obesity and hearing loss. The better you take care of yourself, the better your memory is likely to be. In addition, review your medications with your doctor regularly. Various medications can affect memory.

How is Alzheimer’s disease treated?

Alzheimer’s disease is complex, and it is unlikely that any one drug or other intervention will successfully treat it. Current approaches focus on helping people maintain mental function, manage behavioral symptoms, and slow down the symptoms of disease.

Several prescription drugs are currently approved by the U.S. Food and Drug Administration (FDA) to treat people who have been diagnosed with Alzheimer’s disease. Treating the symptoms of Alzheimer’s can provide people with comfort, dignity, and independence for a longer period of time and can encourage and assist their caregivers as well.

Most medicines work best for people in the early or middle stages of Alzheimer’s. For example, they can slow down some symptoms, such as memory loss, for a time. It is important to understand that none of these medications stops the disease itself.

Treatment for mild to moderate Alzheimer’s disease

Medications called cholinesterase inhibitors are prescribed for mild to moderate Alzheimer’s disease. These drugs may help reduce some symptoms and help control some behavioral symptoms. The medications are Razadyne® (galantamine), Exelon® (rivastigmine), and Aricept® (donepezil).

Scientists do not yet fully understand how cholinesterase inhibitors work to treat Alzheimer’s disease, but research indicates that they prevent the breakdown of acetylcholine, a brain chemical believed to be important for memory and thinking. As Alzheimer’s progresses, the brain produces less and less acetylcholine; therefore, cholinesterase inhibitors may eventually lose their effect.

No published study directly compares these drugs. Because they work in a similar way, switching from one of these drugs to another probably will not produce significantly different results. However, an Alzheimer’s patient may respond better to one drug than another.

Treatment for moderate to severe Alzheimer’s disease

A medication known as Namenda® (memantine), an N-methyl D-aspartate (NMDA) antagonist, is prescribed to treat moderate to severe Alzheimer’s disease. This drug’s main effect is to decrease symptoms, which could allow some people to maintain certain daily functions a little longer than they would without the medication. For example, Namenda® may help a person in the later stages of the disease maintain his or her ability to use the bathroom independently for several more months, a benefit for both the person with Alzheimer’s and caregivers.

The FDA has also approved Aricept®, the Exelon® patch, and Namzaric®, a combination of Namenda® and Aricept®, for the treatment of moderate to severe Alzheimer’s disease.

Namenda® is believed to work by regulating glutamate, an important brain chemical. When produced in excessive amounts, glutamate may lead to brain cell death. Because NMDA antagonists work differently from cholinesterase inhibitors, the two types of drugs can be prescribed in combination.

Table 2. Alzheimer’s disease medications

Managing behavior

Common behavioral symptoms of Alzheimer’s disease include sleeplessness, wandering, agitation, anxiety, aggression, restlessness, and depression. Scientists are learning why these symptoms occur and are studying new treatments—drug and nondrug—to manage them. Research has shown that treating behavioral symptoms can make people with Alzheimer’s more comfortable and makes things easier for caregivers.

Examples of medicines used to help with depression, aggression, restlessness, and anxiety include:

• Celexa® (citalopram)
• Remeron® (mirtazapine)
• Zoloft® (sertraline)
• Wellbutrin® (bupropion)
• Cymbalta® (duloxetine)
• Tofranil® (imipramine)

Experts agree that medicines to treat these behavior problems should be used only after other strategies that don’t use medicine have been tried.

Short term memory loss

Short-term memory also referred to as short-term storage, or primary or active memory indicates different systems of memory involved in the retention of pieces of information (memory chunks) for a relatively short time (usually up to 30 seconds) ¹. In contrast, long-term memory may hold an indefinite amount of information ¹. The difference between the two memories, however, is not just in the ‘time’ variable but is above all functional. Nevertheless, the two systems are closely related. Practically, short-term memory works as a kind of “scratchpad” for temporary recall of a limited number of data (in the verbal domain, roughly the George Miller’s ‘magical’ number 7 +/- 2 items) that come from the sensory register and are ready to be processed through attention and recognition.[1] On the other side, information collected in the long-term memory storage consist of memories for the performance of actions or skills (i.e., procedural memories, “knowing how”) and memories of facts, rules, concepts, and events (i.e., declarative memories, “knowing that”). Declarative memory includes semantic and episodic memory. The former concerns broad knowledge of facts, rules, concepts, and propositions (‘general knowledge’), the latter is related to personal and experienced events and the contexts in which they occurred (‘personal recollection’).

The capacity of the short-term memory has limitations in the amount and duration of information it can maintain. In contrast, long-term memory features a seemingly unlimited capacity that can last years. The functional distinctions between systems of memory storing and the exact mechanisms for how memories transfer from short-term to long-term memory remain a controversial issue. Do short-term memory and long-term memory represent one or more systems with specific subsystems? Although the short-term memory probably represents a sub-structure of the long-term memory, which is a sort of long-term activated storage, rather than looking for a ‘physical’ division, it seems appropriate to verify the mechanisms of transition from a memory that is only a passage to a lasting memory. Although the classic multi-modal model proposed that storage of short-term memories occurs automatically without manipulation, the matter seems to be more involved. The phenomenon concerns quantitative (number of memories) and qualitative (quality of memory) features.

The impairment of short-term memory involves forgetting information to which the subject has been recently exposed. An individual with signs of losing short-term memory, indeed, asks for the same questions repeatedly, forgets where he just put something, forgets recent events or something he saw or read recently. The loss of immediate memory is also termed as fixation amnesia. The clinical features of short-term memory impairment, however, are variable and depend on the underlying cause for the memory alteration. Within the short-term memory, different memory domains such as verbal or visuospatial components, and in different degrees, can be altered. In most cases, the memory alterations are blurred and last as long as the pathology that caused them, or resolves over weeks or months (e.g., postoperative cognitive dysfunction).

Short term memory loss causes

Different clinical conditions including, strokes, brain aneurysms, traumatic brain injuries, primitive or metastatic tumors, and infectious diseases (e.g., encephalitis) may impair various components of short-term memory. However, the damage to the short-term memory is seldom selective. For example, aneurysm rupture can lead to short-term memory loss, as well as long-term memory loss. Apart from diseases which induce short-term memory alterations through direct neural damage, a wide range of medical conditions such as systemic infections, thyroid diseases, surgery (e.g., neuroinflammation-mediated postoperative delirium and postoperative cognitive dysfunction ² or psychiatric diseases (e.g., depression) or psychological (e.g., psychological trauma) can also impact short-term memory. In this regard, pieces of evidence demonstrated that violence exposure during childhood impairs cognitive processes, including memory (psychogenic amnesia) ³. Cancer treatments, including radiation and chemotherapy, can induce short-term memory damage through a complex neuroinflammation mechanism ⁴.

Neurodegenerative conditions are paramount causes of memory impairment. For instance, one of the first signs of dementia is short-term memory loss. In particular, memory loss (without interference in daily life or independent function) is the main feature of mild cognitive impairment which represents the stage between the expected cognitive decline of normal aging and the more severe decline observed in Alzheimer disease. Moreover, alterations in different memory domains have been shown in Parkinson disease ⁵, in those affected by Huntington disease ⁶ and in primary progressive aphasia ⁷.

Other conditions that can impair memory tasks are alcohol and drug abuse (e.g., marijuana), heavy cigarette smoking, sleep deprivation, severe stress, and vitamin B12 deficiency. Prolonged high alcohol intake can lead to Korsakoff syndrome, which is a complex amnestic disorder with neuropsychological sequelae caused by vitamin B1 (thiamine) deficiency. In addition to alcohol, other causes can lead to vitamin B1 deficiency (non-alcoholic Korsakoff syndrome) with related memory disorders, including dietary deficiencies, prolonged vomiting, and eating disorders. Again, Korsakoff-like amnestic syndromes have also presented after brain lesions involving anteromedian thalamus and hippocampus ⁸.

Among other causes of memory impairment, a common side effect of electroconvulsive therapy (ECT) is short-term memory alteration during treatment. A special issue concerns medications-induced memory loss. The list of drugs implicated includes benzodiazepines (BDZs), antiepileptic drugs ⁹, opioids ¹⁰, tricyclic antidepressants ¹¹. Concerning statin use and memory loss, there is weak evidence (observational data, including case reports) ¹². Most of these drugs (e.g., benzodiazepines) act by impairing memory processing and, in turn, can present an obstacle to the consolidation of information ¹³.

In neurodegenerative diseases such as dementia, the decline of short-term memory is generally progressive, involving different domains and, in turn, other memory systems. On the other side, memory loss in mild cognitive impairment can remain unaltered, worsen, or improve. In about 30% of brain aneurysm cases, short-term memory/long-term memory problems disappear over time, although recovery may take weeks. In most cases (e.g., psychogenic amnesia) memories can be recovered for instance through psychological interventions (recover of undeleted files); nevertheless, if amnesia has lasted a long time such as months or years, the recovery is not possible (deleted files), and the subject projects into a new life (the fugue state).

Alcohol-induced Korsakoff syndrome characteristically demonstrates short-term memory/long-term memory impairment (anterograde, retrograde), confabulation (invented memories used to fill memory gaps and blackouts) and psychiatric symptoms. Neurological manifestations associated with thiamine deficiency (Wernicke encephalopathy) can accompany Korsakoff syndrome, and the combination is termed as Wernicke-Korsakoff syndrome.

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