Causes of memory loss

What is memory loss? 

If you’ve noticed changes in your memory, you may wonder whether they’re a natural part of aging or a reason to talk with your healthcare provider. Understanding what memory loss means can help you decide what to do next.

Memory loss is usually categorized as short-term or long-term difficulty recalling information. Short-term issues can be serious or benign. Long-term memory problems are more serious and can interfere with daily life and activities. Memory loss can be a natural part of the aging process, but many other factors can influence it. Common causes include stress, depression, anxiety, and Alzheimer’s disease. If you or a family member is experiencing symptoms that could indicate memory loss, make an appointment with your healthcare provider to discuss your concerns and experiences.

Causes of short-term memory loss 

Short-term memory loss can have many causes, including the natural aging process. As we age, we lose brain cells, particularly in certain regions such as the hippocampus. This seahorse-shaped area of the brain helps form new memories and connect them to emotions. As people experiencing short-term memory loss lose brain cells, they may also have decreased amounts of acetylcholine, a naturally occurring chemical that allows brain cells to communicate. People living with Alzheimer’s may experience short-term memory loss because of the disease. Brain injuries, seizures, or stroke may also cause short-term memory loss.

What does short-term memory loss look like? Although forgetfulness can be a normal part of aging, short-term memory loss is the inability to form memories of recent experiences. Common signs include:

• Forgetting something you recently saw or read 

• Having difficulty recalling recent events in your life 

• Asking the same questions repeatedly 

• Forgetting where you put something 

• Having trouble processing new information you just heard, such as a recipe or directions 

• Having trouble multitasking 

Causes of long-term memory loss 

Scientists continue to debate the underlying causes of long-term memory loss. As with short-term memory loss, it is associated with the depletion of brain cells in regions that are important for storing memories. Mental health conditions, stress, and medications can also affect our ability to access long-term memories. Diseases such as Alzheimer’s disease, dementia, and epilepsy are also known to cause this type of irreversible memory loss.

Long-term memory allows us to recall past events and experiences. It also plays a key role in managing routines and daily tasks. Familiar activities, such as finding the way home, cooking a meal, or completing routine tasks, can become much more difficult when someone is experiencing long-term memory problems. 

Signs of long-term memory problems can include:

• Changes in behavior or mood 

• Consistently mixing up words or using the wrong words 

• Consistently forgetting common words 

• Forgetting the names of family members or close friends 

• Being unable to perform routine tasks 

• Getting lost in familiar places 

• Forgetting what you were thinking about 

• Taking a long time to complete simple tasks 

Mild cognitive impairment (MCI) 

MCI is a memory impairment that can be considered early-stage Alzheimer’s disease. MCI is a cognitive condition that affects how someone thinks and remembers. No single factor causes this decline, but depression, diabetes, a history of head injuries, genetic factors, and stroke can contribute to it. The underlying pathology of MCI is similar to that seen in Alzheimer’s disease and involves the buildup of toxic products that result in the death of neurons.

According to the Alzheimer’s Association, approximately 12%–18% of people aged 60 or older are living with MCI. Every person’s experience is different, but MCI is generally considered less severe than dementia or Alzheimer’s. In most cases, the person can still manage daily activities and care for themselves.

The medical community is still learning about MCI. For many people, MCI eventually progresses to dementia caused by Alzheimer’s disease or another memory disorder. However, this progression isn’t guaranteed, and many older adults live out their lives without an Alzheimer’s diagnosis.

Common symptoms of MCI 

• Having trouble remembering words 

• Having difficulty following conversations 

• Having difficulty making decisions 

• Losing things 

• Forgetting appointments 

Other causes of memory loss 

Now that you understand the general categories of memory loss and some common symptoms, it can help to look more closely at its possible causes and how they may appear. 

Alzheimer’s disease 

Alzheimer’s is the most common type of dementia and can cause progressive, irreversible memory loss. Memory loss is often an early symptom, but others can include difficulty thinking, confusion, mood swings, personality changes, trouble speaking coherently, problems with judgment and reasoning, and difficulty performing daily tasks. Other types of dementia can also lead to memory loss and behavioral changes that may go unnoticed. If you think you or someone you love might have dementia, talk with your doctor. Physicians may use behavioral tests, such as the Mini-Mental State Examination (MMSE), to diagnose Alzheimer’s disease. 

Medication 

Some medications, or combinations of medications, can cause forgetfulness and confusion. Only make decisions about continuing or stopping a medication with input from your physician.

Alcohol use 

Chronic alcohol misuse reduces overall brain health and creates a risk for a specific disease associated with memory loss. Alcohol can also interact with medications and lead to poor health outcomes, especially when someone takes several medications at once or has taken them regularly over time. The University of Michigan notes that combining alcohol with depressants, stimulants, or opioids can result in severe cognitive difficulties, including memory loss. 

Sleep deprivation or lack of sleep 

Research has shown that memory consolidation, the process of moving memories from short-term to long-term storage, occurs during sleep. This highlights the importance of sleep for memory formation. Recent research has also shown that, while we sleep, important cells in the brain clear toxic byproducts and help brain cells function in a healthy way. Sleep is important for both memory and overall brain health.

One chronic problem associated with insufficient sleep is sleep apnea. Sleep apnea is a disorder in which breathing repeatedly stops and starts. This irregular breathing can reduce oxygen to the brain and may eventually lead to memory loss and impairment. Fortunately, treatment options are available for sleep apnea. Sleep studies can help identify and treat other causes of sleep impairment.

Mental health 

It’s easy to focus on physical health as you age, but mental health can also play a role in memory loss. Mental health conditions such as depression have been positively correlated with memory loss. Data also suggests that stress and anxiety can reduce memory formation and retrieval. The reason isn’t known, but it may involve the overactivation of hormones involved in the fight-or-flight response.

To help limit the effect of mental health conditions on your memory and overall aging experience, try to prioritize sleep and attend wellness events, such as stress-reduction programs. You can also speak with your doctor about whether antidepressant medication may help relieve some symptoms.

Diet and nutrition 

Nutritional deficiencies are common among older adults, who may also face cognitive problems when their diets lack vitamins and nutrients. Emerging evidence suggests that a diet rich in grains, fruit, vegetables, and fish, and low in trans fats and red meat, may support brain performance, including memory. Many older adults have a vitamin B-12 deficiency, and B-12 plays an important role in maintaining healthy nerve cells and red blood cells. Foods rich in B-12 include milk, cheese, fish, and eggs. 

Other conditions 

• An infection in the brain or a tumor can cause memory problems or other dementia-like symptoms. Your physician may recommend blood tests and/or brain imaging to diagnose such a condition. 

• Concussions may cause short-term or long-term memory loss. Researchers continue to investigate the connection between concussions, repetitive head impacts, and long-term memory problems. 

• Oxygen deprivation from a stroke, traumatic brain injury, or drowning accident can cause temporary memory loss if specific regions of the brain are affected. 

• Seizures are caused by abnormal electrical activity in the brain. For reasons that aren’t understood, seizures seem to affect areas close to the hippocampus, which is responsible for making new memories. Memory problems occur because of the gradual loss of brain cells in the hippocampus. 

• Stroke can cause brain cell death and memory loss. Depending on the severity of the stroke, memory loss can be permanent. However, someone may also recover slowly through cognitive rehabilitation. 

• Transient global amnesia (TGA) is a rare condition in which someone may experience sudden memory loss. When a TGA episode occurs, the person is unable to recall recent events and memories. 

• Hypothyroidism can cause forgetfulness and other problems with thinking. 

• Anesthesia has been reported to have a short-term effect, lasting several days, on memory. 

• Cancer treatments such as chemotherapy, radiation, and bone marrow transplants can cause memory loss. 

Memory loss has many potential causes, including long-term stress, brain trauma, aging, or an aging-related disease. It may also be connected to biological factors such as genetics, disease processes, or aging-related deterioration in brain function. Some medications and substance use problems, including alcohol addiction, may also contribute to cognitive impairment. These factors typically cause short-term rather than long-term memory loss. Although this list doesn’t cover every possible cause, it provides an overview of what can contribute to memory problems. It’s important to seek professional help instead of trying to diagnose yourself because there may be more to your memory loss than you realize. 

When to see a doctor 

Although short-term and long-term memory changes can be a normal part of aging, it’s still wise to discuss any concerning symptoms with your doctor. If memory loss begins to interfere with your daily life and activities, seek professional advice right away.

In addition to testing your overall thinking skills, your doctor may order blood tests and brain imaging to determine whether your condition can be reversed. Your doctor may also refer you to a neurologist, psychiatrist, psychologist, or geriatrician to help diagnose dementia or another memory disorder.

Memory loss treatment 

Getting a proper diagnosis is important because some memory loss may be reversible with treatment. An early diagnosis of a disease such as Alzheimer’s can increase treatment options. Your doctor can help you find resources such as the Alzheimer’s Association, where you can access more information, emotional support, and even financial assistance or advice. 

A special note for family caregivers 

If you’re a family caregiver supporting someone with a memory-related diagnosis, support is available for you, too. Navigating your relationship and role while someone you love undergoes a memory assessment or lives with a diagnosis can be difficult. The Alzheimer’s Association offers a helpful collection of resources and support groups for family caregivers supporting people living with Alzheimer’s disease. Whether you find support through a formal group or an informal network, make sure you also take time to care for yourself.