Introduction
Memory is humans’ greatest blessing and a curse. Even in normal living, people complain about their inability to forget bad happenings in life. Still, some of them complain about memory loss, especially from their mid-age. It can be as mild and unimportant as a rare forgetfulness but it can develop into disease conditions that affects their daily living. Memory disorders are disorders of the ability to reason, remember, make decisions and communicate. There are a wide variety of memory disorders, including dementia, Alzheimer’s disease, mild cognitive impairment, vascular cognitive impairment and hydrocephalus.
Some types of memory disorders can appear suddenly, while others may be present years before symptoms become apparent. Amnesia refers to the loss of memories, such as facts, information and experiences. People with amnesia usually know who they are. But they may have trouble learning new information and forming new memories.
In other words, a partial or total loss of memory is called Amnesia. It can be caused by damage to areas of the brain that are vital for memory processing. Unlike a temporary episode of memory loss (transient global amnesia), amnesia can be permanent.
There’s no specific treatment for amnesia, but techniques for enhancing memory and psychological support can help people with amnesia and their families.
Signs & symptoms
The two main features of amnesia are:
- Difficulty learning new information following the onset of amnesia (anterograde amnesia)
- Difficulty remembering past events and previously familiar information (retrograde amnesia)
Most people with amnesia have problems with short-term memory — they can’t retain new information. Recent memories are most likely to be lost, while more remote or deeply ingrained memories may be spared.
Amnesia and dementia are different. Dementia often includes memory loss, but it also involves other significant cognitive problems that lead to a decline in daily functioning.
Types of Memory Disorders with their signs and symptoms
Dementia
It is the name for a group of brain conditions in which the patient finds difficulty to remember, reason, and communicate. Dementia is a descriptive term rather than a diagnosis. The most common form of dementia is Alzheimer disease. Other types include vascular dementia, frontotemporal dementia, and Lewy body dementia. It is different from changes due to normal ageing. It’s caused by ongoing damage to cells in the brain.
Symptoms differ depending on which parts of the brain are affected and the stage of the disease. The most common symptoms include:
Memory loss, including trouble with directions and familiar tasks
Language problems, such as trouble getting words out or understanding what is said
Difficulty with planning, organizing, concentration, and judgment. This includes people not being able to recognize their own symptoms.
Changes in behaviour and personality
Dementia is a progressive disease or it gets worse over time. Symptoms differ for each person, but there are 3 basic stages. Each may last from months to years:
In the early stage, a person may seem forgetful, confused, or have changes in behaviour. However, he or she may still be able to handle most tasks without help.
In the middle stage, more and more help will be needed with daily tasks. A person may have trouble recognizing friends and family members, may start to wander, or get lost in familiar places. He or she may also become restless or moody.
In the late stage, Alzheimer’s can cause severe problems with memory, judgment, and other skills. Help is needed with nearly every aspect of daily life.
Alzheimer’s disease
It is a condition usually affects older people but it can happen in late 40’s. Being the most common cause of dementia, it is the illness of brain that gets worse over time. Alzheimer’s disease causes a series of changes in brain cells. It makes some nerves to form clumps and tangles, and lose some of their connections to other nerves. Age is the most important risk factor for Alzheimer’s disease. Other risk factors include heredity, diabetes, hypertension, traumatic brain injury and poor nutrition.
The disease causes changes in behaviour and thinking known as dementia. The symptoms include:
Memory loss
Confusion
Restlessness
Personality and behaviour changes
Problems with judgement
Communication problems
Inability to follow directions
Lack of emotions
As the disease progresses the patient may become completely dependant on others to ensure adequate nutrition and proper hygiene.
Encephalitis
Encephalitis is inflammation and swelling of the brain. This leads to changes in neurological function, resulting in mental confusion and seizures. Viruses cause most of the encephalitis cases. Many vaccines like measles, rubella, mumps etc. have lowered the rate of infection but many other viruses cause encephalitis including herpes simplex and rabies. Encephalitis can also occur due to bacteria, ticks (Lyme disease), mosquitoes (West Nile virus) and cats(toxoplasmosis).
Along with problems of memory and coordination, a wide variety of other neurologic manifestations may occur. These include:
Parkinsonism – slowness of movement, increased rigidity in the arms and/or legs, problems with walking
Seizures
Weakness or sensory changes affecting one side of the body
Problems with speech, swallowing, or double vision.
Loss of ability to perform learned motor movements
Inattention to visual or sensory stimuli on one side of the body
Tremor
Headache
Frontotemporal dementia
Being another common cause of dementia, it is a group of disorders that occur when nerve cells in the frontal and temporal lobes of the brain are lost. This causes the lobes to shrink. FTD can affect behaviour, personality, language, and movement.
These disorders are among the most common dementias that strike at younger ages. Symptoms typically start between the ages of 40 and 65, but FTD can strike young adults and those who are older. FTD affects men and women equally.
The most common types of FTD are:
Frontal variant. This form of FTD affects behaviour and personality.
Primary progressive aphasia. Aphasia means difficulty communicating. This form has two subtypes: Progressive non-fluent aphasia, which affects the ability to speak. Semantic dementia, which affects the ability to use and understand language.
A less common form of FTD affects movement, causing symptoms similar to Parkinson disease or amyotrophic lateral sclerosis (Lou Gehrig’s disease).
The cause of FTD is unknown. Researchers have linked certain subtypes of FTD to mutations on several genes. Some people with FTD have tiny structures, called Pick bodies, in their brain cells. Pick bodies contain an abnormal amount or type of protein.Damage to the frontal lobe of the brain may impact important functions.
Common symptoms involve dramatic changes in behaviour and personality.
These may include:
An increased tendency to make socially inappropriate comments or actions
Decreased empathy, or new difficulties understanding how one’s actions may impact others
Difficulties with logical judgments or understanding the relationship between cause and effect
Changes in sexual behaviours
Aggressive behaviours or actions
Decline in personal hygiene, toileting habits, etc.
Severe mental rigidity
Language abnormalities, such as being unable to express language, find words or understand the meaning of words
Inattention, increased distractibility or a tendency to jump from one topic to another
Difficulty initiating or completing tasks
Significant changes in eating patterns
In addition to cognitive impairments, neurologic symptoms may occur including:
Parkinsonism: slowness of movement (bradykinesia), increased rigidity in the arms and/or legs, problems with walking (short stride length or a “shuffling” gait)
Tremor
Muscle spasms and/or rippling of the muscles underneath the skin
Seizures
Dementia with Lewy bodies
It is a form of progressive dementia caused by degeneration of the tissues in the brain. DLB may be genetic, but it is not always clear why someone develops it.
People with DLB have a build-up of abnormal protein particles in their brain tissue, called Lewy bodies. Lewy bodies are also found in the brain tissue of people with Parkinson disease (PD) and Alzheimer disease (AD). However, in these conditions, the Lewy bodies are generally found in different parts of the brain.
The presence of Lewy bodies in DLB, PD, and AD suggests a connection among these conditions. But scientists haven’t yet figured out what the connection is.
DLB affects a person’s ability to think, reason, and process information. It can also affect movement, personality and memory. DLB becomes more prevalent with age. It often starts when a person is in his or her 60s and 70s. DLB is progressive, which means it continues to develop over time. There are several types of dementia with different causes.
The main sign of DLB is a progressive decline in things like memory, thinking, and problem solving. This decline is enough to affect the ability to work and do normal daily activities. Although memory may be affected, it isn’t usually as impaired as in someone with Alzheimer disease.
DLB is generally diagnosed when at least 2 of the following features are also present with dementia:
Changes in attention and alertness. These changes may last for hours or days. Signs of these changes include staring into space, lethargy, drowsiness, and disorganized speech.
Visual hallucinations. These hallucinations recur and are very detailed. They generally don’t bother the person having them.
Other signs and symptoms seen in DLB include:
Depression
Sleep disorder that affects REM sleep, causing vivid dreams with body movement
Dizziness, feeling lightheaded, fainting, or falling
Urinary incontinence
In DLB, memory problems often occur later in the disease. DLB can be confused with other forms of dementia, but it also has unique features, such as hallucinations and delirium.
Mild cognitive impairment (MCI)
It is an intermediate state between normal thinking & memory (cognition) and dementia. Patients with mild cognitive impairment can have difficulty with memory, language, thinking and judgment that are greater than would be expected for their age. People with MCI may be at an increased risk for developing Alzheimer’s Disease.
Patients with a family history of Alzheimer’s and dementia are at greater risk for developing MCI. Other risk factors include age, high cholesterol, high blood pressure, diabetes and hypothyroidism.
Vascular cognitive impairment
It is the second most common form of dementia after Alzheimer disease. It’s caused when decreased blood flow damages brain tissue. Blood flow to brain tissue may be reduced by a partial blockage or completely blocked by a blood clot.
Symptoms of vascular dementia may develop gradually, or may become apparent after a stroke or major surgery, such as heart bypass surgery or abdominal surgery.
Dementia and other related diseases and conditions are hard to tell apart because they share similar signs and symptoms. Although vascular dementia is caused by problems with blood flow to the brain, this blood flow problem can develop differently. Examples of vascular dementia include:
Mixed dementia. This type occurs when symptoms of both vascular dementia and Alzheimer’s exist.
Multi-infarct dementia. This occurs after repeated small, often “silent,” blockages affect blood flow to a certain part of the brain. The changes that occur after each blockage may not be apparent, but over time, the combined effect starts to cause symptoms of impairment. Multi-infarct dementia is also called vascular cognitive impairment.
The effect of decreased or no blood flow on the brain depends on the size and location of the area affected. If a very small area in a part of the brain that controls memory is affected, for example, you may be “forgetful” but it doesn’t necessarily change your ability to carry on normal activities. If a larger area is affected, you may have trouble thinking clearly or solving problems, or greater memory problems that do change your ability to function normally.
Vascular dementia is caused by a lack of blood flow to a part of the brain. Blood flow may be decreased or interrupted by:
Blood clots
Bleeding because of a ruptured blood vessel (such as from a stroke)
Damage to a blood vessel from atherosclerosis, infection, high blood pressure, or other causes, such as an autoimmune disorder
Symptoms of vascular cognitive impairment (VCI) differ from the early symptoms of Alzheimer’s disease. Given the varied definitions of VCI, it is not surprising that clinical symptoms vary significantly in individual patients.
The symptoms of vascular dementia depend on the location and amount of brain tissue involved. Vascular dementia symptoms may appear suddenly after a stroke, or gradually over time. Symptoms may get worse after another stroke, a heart attack, or major surgery. These are signs and symptoms of vascular dementia
Increased trouble carrying out normal daily activities because of problems with concentration, communication, or inability to carry out instructions
Memory problems, although short-term memory may not be affected
Confusion, which may increase at night (known as “sundown syndrome”)
Stroke symptoms, such as sudden weakness and trouble with speech
Personality changes
Mood changes, such as depression or irritability
Stride changes when walking too fast, shuffling steps
Problems with movement and/or balance
Urinary problems, such as urgency or incontinence
Tremors
Causes
Memory disorders can be caused by one or more factors, including:
- aging
- trauma/injury
- substance abuse
- heredity (inheriting genes associated with Alzheimer’s or Huntington’s disease)
- narrowing of the arteries that provide blood flow to the brain
- cardiovascular disease
- untreated infectious or metabolic disease
- brain tumours
- vitamin deficiencies
- Certain medications
- Brain surgery
Pathophysiology
The neuropathological hallmarks of the atrophy process in Alzheimer’s Disease are the presence of senile plaques (amyloid deposits) and neurofibrillary tangles found in autopsied brains. Neurofibrillary tangles are composed of hyperphosphorylated tau protein located within neurons, whereas senile plaques are made up largely of amyloid-P species aggregating in the extracellular space. These neuropathological changes start in the entorhinal cortex and hippocampal formations, later spreading into other temporal, parietal, and finally frontal association cortices. The first lesions appear in poorly myelinated limbic neurons in system areas related to memory and learning, such as the hippocampus and the association cortex. Highly myelinated neurons are only affected in the final phases of the disease. Low myelinization increases the overall energy expenditure of neurons. In addition, subcortical neuron loss occurs in the nucleus basalis of Meynert and the locus ceruleus, impairing the cholinergic and noradrenergic transmitter systems in the neocortex. The parietal lobe, along with certain areas of the prefrontal lobe, is one of the last areas of the human brain to myelinate, and many of its neurons remain poorly myelinated for the entire lifespan, which may explain their vulnerability to factors capable of triggering Alzheimer’s disease. The atrophy runs slowly, but while in healthy aging only 0.2% to 0.41% of the brain volume vanishes per year, the rates in Alzheimer’s disease may be ten times that, and in especially vulnerable regions like the hippocampal formation atrophy rates might be even more devastatingly high. In terms of neuropsychological tests, regional atrophy, and glucose metabolism correlate well with test results. Left hippocampal Gray matter volume, for example, significantly correlates with performance in memory tasks, and left temporal Gray-matter volume is related to performance in language tasks.
Diagnosis
Proper diagnosis is the initial and important step. Many medical conditions that cause memory loss are treatable when identified early.
It includes a thorough history taking, physical examination and asking some questions.
Tests for proper diagnosis also include:
- cognitive testing to check your thinking ability
- blood tests to look for various conditions including vitamin B-12 deficiency and thyroid disease
- imaging tests such as magnetic resonance imaging (MRI) or computed tomography (CT) scan
- electroencephalogram (EEG) to measure the electrical activity of the brain
- spinal tap
- cerebral angiography, which is an X-ray to see how blood flows through the brain
Treatments
As the degeneration and damage to memory loss due to dementia/Alzheimer’s disease are irreversible in most of the cases, medications can only help improve the daily life quality of the patient.
Mostly there are two types of medications used in dementia.
Cholinesterase inhibitors and Memantine to treat the cognitive symptoms (memory loss, confusion, and problems with thinking and reasoning) of Alzheimer’s disease.
Many of the medications cause side effects like nausea, vomiting, loss of appetite, increased frequency of bowel movements, headache, constipation, confusion and dizziness.
Therapies like cognitive behavioural therapy, meditation, yoga etc. can help in improving the quality of life.
Prevention
It is important to minimize your chance of a brain injury/damage. For example:
- Avoid excessive alcohol use.
- Wear a helmet when bicycling and a seat belt when driving.
- Treat any infection quickly so that it doesn’t have a chance to spread to the brain.
- Symptoms such as a severe headache or one-sided numbness or paralysis should be managed quickly as they can be a sign of stroke or brain aneurysm,.
Prognosis
The overall outcome of memory disorders is not good. It is impossible to repair the damage already happened. But it may be controlled with medications and the progress can be slowed down. The memory loss may be for a short time and then resolve (transient). Or, it may not go away, and, depending on the cause, it can get worse over time. In severe cases, such memory impairment may interfere with daily living activities.
Some cases of short-term memory loss are reversible with treatment. For example, memory loss from medications may resolve with a change in medication. Nutritional supplements can be useful against memory loss caused by a nutritional deficiency.
Complications
Amnesia causes problems in daily activities and quality of life. It affects the patient and the family. The syndrome can cause problems at work, at school and in social settings. There is increased chances of injury, accidents etc.
Disease & Ayurveda
Smritibhramsa
Nidana
Dhatukshaya (depletion of body tissues)-like in degeneration due to old age
Margavarodha (obstruction in channels)-like in blocks in blood vessels
Purvaaroopa
Not mentioned
Samprapti
Due to the causative factors, Vaata dosha gets vitiated. Vaata, being the carrier of the other two doshas,Pitta & Kapha causes vitiation of them. All these vitiated doshas get lodged in manovahasrotas(Channels in brain) and develops the disease.
Lakshana
Smritibhramsa-loss of memory
Divisions
Not mentioned
Prognosis
Yaapya
Chikithsa
Samana
Aamapachana
Agnideepana
Rasayana
Brumhana
Sodhana
Snehanam
Swedanam
Mriduvirechanam
Commonly used medicines
Manasamitravatakam
Aswagandharishtam
Chyavanaprasam
Braahmarasayanam
Brands available
AVS Kottakal
AVP Coimbatore
SNA oushadhasala
Vaidyaratnam oushadhasala
Home remedies
No home remedies are proven to cure memory disorders. But supplements and well-balanced diet may be helpful.
Diet
- To be avoided
Heavy meals and difficult to digest foods – cause indigestion.
Junk foods- cause disturbance in digestion and reduces the bioavailability of the medicine
Carbonated drinks – makes the stomach more acidic and disturbed digestion
Refrigerated and frozen foods – causes weak and sluggish digestion by weakening Agni (digestive fire)
Curd – causes vidaaha and thereby many other diseases
- To be added
Light meals and easily digestible foods
Green gram, soups.
Fresh fruits
Freshly cooked and warm food processed with cumin seeds, ginger, black pepper, ajwain etc
Behaviour:
Avoid stress
Better to avoid exposure to excessive sunlight wind rain or dust.
Maintain a regular food and sleep schedule.
Avoid holding or forcing the urges like urine, faeces, cough, sneeze etc.
Avoid sedentary lifestyle.
Yoga
Regular stretching and mild cardio exercises are advised. Also, specific yogacharya including naadisuddhi pranayama, bhujangaasana, pavanamuktasana is recommended.
Regular exercise helps improve bioavailability of the medicine and food ingested and leads to positive health.
Yoga can maintain harmony within the body and with the surrounding system.
Pavanamuktasana
Nadisudhi pranayama
Bhujangasana
Simple exercises for lungs and heart health
All the exercises and physical exertions must be decided and done under the supervision of a medical expert only.
Research articles
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1002292/?page=2