Short-term and long-term memory function differently, and different issues may affect each one. While occasionally forgetting things is a typical sign of aging, some memory issues may indicate an underlying condition.

Short-term memory is the capacity to recall a small amount of information from a recent time period. Long-term memory is the capacity to recall memories from a longer time ago.

People can sometimes experience issues with their short-term or long-term memory. Depending on the underlying cause, these issues may be temporary, intermittent, or permanent.

This article outlines the various causes of short-term and long-term memory loss. We also outline the differences between typical age-related memory loss and dementia.

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Short-term memory refers to the brain systems involved in storing information for a short period, usually up to around 30 seconds. Short-term memory can typically hold around seven pieces of information at a time.

Many events and memories compete for attention in the brain, and the brain does not store all of them. However, long-term memory refers to brain systems involved in storing events for a long time.

Almost any condition that causes brain damage or interferes with brain function or chemistry has the potential to cause short-term or long-term memory loss, or both.

Possible causes of memory loss include the following:

Aging

Aging can cause brain changes that may affect both short-term and long-term memory. Short-term memory problems may present as difficulty learning new information. Long-term memory problems may present as difficulty retrieving previously learned information or memories.

Age-related memory problems are typically mild or temporary. Serious memory problems may be a sign of an underlying condition, such as dementia.

Sleep deprivation

Scientists generally agree that sleep is important for memory consolidation. This is the process of preserving key memories and discarding excessive or irrelevant information. As such, getting an insufficient amount of sleep each night can interfere with short-term memory. Unless a person has an underlying sleep problem, these memory issues should resolve when people manage to improve their sleep schedule.

Some sleep problems that could increase the risk of memory problems include:

  • Insomnia: Difficulty getting to sleep or staying asleep throughout the night.
  • Narcolepsy: A condition characterized by periods of excessive sleepiness or sudden and uncontrolled sleep episodes.
  • Sleep apnea: A condition in which breathing repeatedly stops and starts while a person sleeps.

Alcohol consumption

Drinking too much alcohol can impair short-term memory.

Excessive alcohol consumption over time can cause permanent brain changes that impact both short- and long-term memory.

Recreational drug use

Some recreational drugs can interfere with brain chemistry, triggering short-term memory impairments. Examples include cannabis and psychedelics.

Chronic drug use can cause irreversible long-term memory loss.

Infections

Many infections can affect the brain directly, causing cognitive changes, such as memory loss or delirium. These infections may be viral, bacterial, or fungal.

Some infections that can cause memory loss include:

In some cases, treating the underlying infection helps to resolve the memory loss.

Vision or hearing loss

Problems with vision or hearing can affect a person’s ability to take in new information and make new memories.

Short-term memory problems often resolve once a person begins wearing devices to correct or compensate for their vision or hearing loss.

Traumatic brain injuries

A traumatic brain injury (TBI) is any injury that affects brain function. A TBI has the potential to cause short-term or long-term memory problems, depending on the severity of the injury and the regions of the brain involved.

A concussion is a mild TBI that can impair short-term memory or affect a person’s ability to recall information from long-term memory. Concussion-induced memory problems typically last less than 24 hours.

Severe or penetrating injuries can cause memory loss lasting longer than 7 days. If the brain damage is permanent, the memory loss may also be permanent.

Neurodegenerative conditions

Neurodegenerative conditions cause progressive damage to cells in the brain and nervous system. This damage may eventually lead to irreversible memory loss.

The most common neurodegenerative conditions associated with memory loss are Alzheimer’s disease (AD) and Parkinson’s disease (PD).

Short-term memory loss is a common sign of AD, especially during the earlier stages of the disease. As AD progresses and becomes more severe, the condition may also begin to impact long-term memory. AD usually affects episodic memory, which involves events, rather than procedural memory, which helps people remember skills.

People with PD can develop memory problems a year or more following their initial diagnosis.

Learn more about Alzheimer’s and dementia here and Parkinson’s disease here

Endocrine conditions

Endocrine conditions are those that affect the endocrine system. This system is composed of a network of glands that produce and secrete hormones to enable or support bodily functions.

Conditions that affect the endocrine system can interfere with brain functioning and may cause memory problems. Examples include:

Cardiovascular conditions

Memory loss and other cognitive impairments can sometimes occur as a result of chronic cardiovascular conditions, such as high blood pressure or “hypertension” and high cholesterol. These conditions can impair blood flow to the brain and can damage blood vessels in the brain itself. This damage can lead to a condition called vascular dementia.

Hypertension and high cholesterol also increase the risk of heart attack and stroke, both of which may cause memory problems by depriving brain cells of the oxygen they need to function. Without oxygen, the brain cells will die. Depending on the location and extent of brain cell death, a person may have lasting memory problems.

Brain bleeds

Bleeding in the brain can starve brain cells of the oxygen they need to function. Depending on the areas of the brain involved, this may result in short-term or long-term memory problems.

If a person receives prompt treatment for a brain bleed, they may be able to recover their memory function. However, severe damage to the brain may result in permanent memory loss.

Abnormal brain growths

Abnormal brain growths, such as brain cysts and tumors, can interrupt blood flow to areas of the brain involved in memory. These areas include the outer part of the brain or “cortex” as well as deep brain regions such as the hippocampus.

Memory problems may resolve following surgery to remove the abnormal brain growth or after taking medication to shrink the growth. In some cases, a person may experience permanent brain damage and memory loss.

Hydrocephalus

Hydrocephalus is the medical term for an accumulation of fluid in the brain. Fluid accumulation can put pressure on brain structures, which can disrupt the flow of blood and oxygen to brain cells. This, in turn, can cause problems with short-term memory.

Hydrocephalus-induced dementia may resolve after the removal of excess fluid from the brain.

Epilepsy

Seizures interfere with the brain’s ability to monitor itself, which is critical for memory. This interference can happen at any of the following stages:

  • Before a seizure: The brain may fail to store memories that formed before a seizure.
  • During a seizure: Loss of consciousness can prevent the brain from forming and storing memories.
  • After a seizure: Confusion following a seizure can impair memory function.
  • Between seizures: Epilepsy can sometimes cause unusual electrical activity in the brain between seizures. This activity can affect attention and memory.

Epilepsy medications can reduce the frequency and severity of seizures, making a person less likely to experience memory problems. However, some epilepsy medications can slow down the speed of information processing in the brain, which can affect memory function.

Chronic pain conditions

Conditions that cause chronic pain can also cause “brain fog,” which a person may experience as:

  • lack of mental clarity
  • inability to focus
  • confusion
  • forgetfulness

Chronic pain conditions that can cause brain fog include:

Brain fog typically resolves following treatment or management of the underlying chronic pain condition.

Mental health conditions

Mental health conditions can change brain chemistry and functioning, and have the potential to cause short-term and long-term memory problems. Examples of such conditions include:

Memory problems associated with mental health conditions typically resolve following successful treatment of the underlying condition.

Vitamin deficiencies

A deficiency in any of the following vitamins can cause changes to memory and cognition:

Memory problems typically resolve once a person addresses the deficiency through diet or supplements.

Medications

Some medications interfere with brain functioning and may trigger temporary memory problems. Examples include:

As a person ages, their brain undergoes age-related changes. These changes may make it harder for the person to learn new things, and they may cause temporary forgetfulness.

Severe memory loss is not a part of typical aging and may be a sign of dementia. This type of memory loss is typically accompanied by other cognitive and behavioral changes.

The table below lists signs and symptoms of typical aging compared with memory loss and dementia:

Typical agingMemory loss and dementia
able to recognize memory loss is happeningunable to identify memory loss
taking longer than usual to learn new thingsbeing unable to learn new things or learning then forgetting them
missing a payment or an appointment every now and thenbeing unable to manage bills and schedules
forgetting which word to use every now and thendifficulty maintaining a conversation
losing things every now and thenmisplacing or losing things very often
making a mistake or an illogical decision from time to timemaking poor or illogical decisions often
forgetting the date every now and thenfrequently losing track of the day or year
having difficulty remembering a word or name every now and thenforgetting the names of friends or family members or familiar objects
forgetting directions or steps in a familiar activity from time to timebeing unable to complete regular tasks or activities without help or at all
forgetting how to use everyday devices from time to timebeing unable to drive, use a computer, or use a phone
forgetting which road to take on the drive to work, home, or the grocery storegetting lost in familiar places
not taking the best care of oneself, such as forgetting to brush teeth every now and then, or not preparing healthy mealsbeing unable to take care of oneself, such as being unable to bathe or feed oneself
repeating oneself or a question sometimesasking the same question repeatedly
getting annoyed with forgetfulness occasionallygetting agitated or very irritated by memory problems

Certain strategies may help a person manage issues with their memory or make the issues easier to deal with. These include:

  • following the same routine each day
  • putting important items in the same place every day
  • making to-do lists or using notes or calendars to keep track of activities and important dates, such as bill payment dates and appointments
  • trying to learn a new skill or hobby
  • staying engaged with activities that stimulate the mind
  • maintaining an active social life
  • establishing healthy sleep habits

Many over-the-counter products claim to improve or restore memory function. However, the National Institute on Aging states there are currently no products that are effective at improving or restoring memory. They add that such products may even interact negatively with other medications a person is taking.

According to some estimates, around 40% of dementia cases may be preventable or possible to delay. Tips for preventing or delaying dementia include:

  • sleeping for around 8 hours each night
  • exercising for at least 2.5 hours per week
  • eating a healthy, balanced diet
  • maintaining a moderate body weight
  • quitting smoking
  • reducing alcohol intake or avoiding alcohol altogether
  • managing stress using relaxation techniques, such as yoga, meditation, or walking in nature
  • controlling or preventing hypertension and high cholesterol by making appropriate lifestyle changes and taking any necessary medications
  • seeking treatment for mental health issues, such as depression, anxiety, and PTSD
  • talking with a doctor about switching medications if a medication interferes with memory
  • receiving recommended routine health tests and screenings
  • reading or playing games that are mentally stimulating
  • maintaining an active social life

If a person has experienced permanent brain damage, their memory problems may be permanent. In most other cases, memory problems typically improve once a person receives treatment for the underlying cause.

See below for common causes of memory problems and their associated treatments:

  • Infections: Depending on the type of infection, a person may receive antibiotics, antivirals, or antifungals.
  • Mental health issues: Depending on the issue, a person may receive:
  • Cardiovascular conditions: A person may receive medications to control hypertension, high cholesterol, or heart disease. People with these conditions may also benefit from lifestyle changes, such as:
    • following a diet that is low in fat, sugar, and salt
    • performing regular exercise to help maintain a moderate weight
    • managing stress levels
  • Chronic stress: People with chronic stress may benefit from the following:
    • talking therapies
    • relaxation therapies
    • meditation or mindfulness
  • Sleep deprivation: A person who experiences sleep deprivation may benefit from the following treatments:
    • avoiding caffeine or other stimulants before bedtime
    • avoiding using electronic devices within an hour or two of going to bed
    • ensuring that the sleep environment is cool, dark, and quiet
  • Visual or auditory impairments: Glasses or contact lenses can help correct vision loss, while hearing aids can help with hearing loss.
  • Brain injury: Surgery may help stop a brain bleed or alleviate pressure on the brain. A person may also receive physical therapy or rehabilitation therapy to help them manage any lasting effects of a TBI.
  • Brain disease: Treatments for brain disease depend on the type of disease a person has. They may include:
    • surgery to remove abnormalities
    • medications to help manage or treat certain conditions
    • rehabilitation therapy to help manage or overcome cognitive impairments following disease
  • Nutrient deficiencies: A person can address nutrient deficiencies by taking the necessary supplements or making appropriate dietary changes.

A person should contact a doctor if memory problems interfere with their daily life or quality of life. Severe memory problems are not an inevitable part of aging. A doctor should assess people with more serious memory symptoms to determine the cause and prescribe treatment where appropriate.

People who have mild cognitive impairment should visit their doctor regularly to monitor changes in their cognition over time.

There are many reasons a person may experience problems with their short-term or long-term memory. Some memory problems are relatively benign and transient, while others may signal an underlying condition that requires treatment.

Aging is a common cause of memory problems. Slowed learning and occasional forgetfulness are a natural part of aging. However, anyone who experiences severe, persistent, or distressing memory problems should see their doctor for a diagnosis.