Some Causes and Features of Memory Loss

Cause

Common Features*

Diagnostic Approach†

Age-related memory changes (age-associated memory impairment)

Occasional forgetfulness of such things as names or the location of car keys

No effect on thinking, other mental functions, or the ability to do daily activities

A doctor's examination alone (particularly a neurologic examination and mental status testing to assess functions such as attention, orientation, and memory)

Mild cognitive impairment

Memory loss that is more severe than expected for a person's age, particularly difficulty remembering recent events and conversations (short-term memory loss)

No effect on the ability to do daily activities

An increased risk of developing dementia

A doctor's examination (particularly a neurologic examination and mental status testing to assess functions such as attention, orientation, and memory)

Sometimes formal neuropsychologic testing, which resembles mental status testing but evaluates function in more detail

Dementia

Memory loss that becomes worse as time passes, eventually with no awareness of the loss

Difficulty using and understanding language, doing usual manual tasks, thinking, and planning (for example, planning and shopping for meals), resulting in not being able to function normally

Disorientation (for example, not knowing the time or location)

Difficulty recognizing faces or common objects

Changes in personality or behavior (for example, becoming irritable, agitated, paranoid, inflexible, or disruptive)

A doctor's examination (particularly a neurologic examination and mental status testing to assess functions such as attention, orientation, and memory)

Usually MRI or CT of the brain to identify causes

Sometimes formal neuropsychologic testing

Sometimes a spinal tap (lumbar puncture) to measure levels of two abnormal proteins (amyloid and tau) that occur in Alzheimer disease

Sometimes blood tests to check for certain causes, such as an underactive thyroid gland (hypothyroidism) or a vitamin deficiency

Depression

Memory loss and awareness of the loss, usually accompanied by intense sadness, and lack of interest in usual pleasures

Sometimes sleep problems (too little or too much), loss of appetite, and slowing of thinking, speech, and general activity

Common among people with dementia, mild cognitive impairment, or age-related changes in memory

A doctor’s examination alone, sometimes with use of standardized questionnaires to identify depression

Medications or drugs, such as

  • Medications with anticholinergic effects, including some antidepressants and many antihistamines (used in OTC sleep aids, cold remedies, and allergy medications)

  • Opioids

  • Medications that help people sleep (sedatives)

  • Alcohol

Use of a medication or drug that can cause memory loss

Often recent use of a new medication, an increase in a medication’s dose, or a change in health that prevents the medication from being processed and eliminated from the body normally, as can occur in kidney or liver disorders

Typically stopping the medication or drug to see whether memory improves

* Features include symptoms and results of the doctor's examination. Features mentioned are typical but not always present.

† Although a doctor's examination is always done, it is mentioned in this column only if the diagnosis can sometimes be made by the doctor's examination alone, without any testing.

CT = computed tomography; MRI = magnetic resonance imaging; OTC = over-the-counter.

In these topics