What are memory disorders?

​​​​​​​Memory disorders are brain-based conditions that affect retention and recollection of memories. Everyone experiences some lapse of memory periodically, and some decline in memory is normal as we age. However, with memory disorders, people have more significant memory loss that may interfere with their work, social activities, personality, behavior, and ability to perform daily tasks. Impairments in memory may be due to many conditions, Alzheimer's disease, vascular dementia caused by small strokes in the brain, diabetes or high blood pressure, normal pressure hydrocephalus (NPH), or even depression.

What is Alzheimer’s disease?

​​​​​​​Alzheimer's disease (AD) is a specific type of dementia and the most common form. It is a progressive, degenerative disease that causes slow decline of nerve cells in the brain. Individuals with AD experience progressive and irreversible loss in thinking abilities, including language and memory. Changes are also witnessed in mood, personality, sleep-wake cycles, and behavior. In AD, nerve cells involved in learning and short-term memory are affected early which is the reason memory loss is one of the first symptoms of Alzheimer's disease.

What is dementia?

​​​​​​​Many different conditions and diseases cause dementia. The term "dementia" is used loosely to describe severe memory loss and impairment in other thinking (or "cognitive") abilities that interfere with the individual's daily life and social interactions.

What is the difference between Alzheimer's disease and dementia?

​​​​​​​Dementia refers to a category of disorders that involve memory loss while Alzheimer's disease is a specific disease. Alzheimer's disease causes dementia, however, several other diseases or conditions, such as stroke, Parkinson's disease, head injury, and vitamin deficiency can also cause dementia.

What are the stages of Alzheimer’s disease?

Alzheimer's disease has three stages: early (mild), middle (moderate), and late (severe).

A person in the early stage of Alzheimer’s may:

  • Find it hard to Remember things.

  • Be repetitive.

  • Get lost in familiar places.

  • Lose things or put them in odd places.

  • Have trouble handling money and paying bills.

  • Take longer than normal to finish daily tasks.

Importantly, the first changes present within the brain may begin 20 or more years before diagnosis.

Those in the middle stage of Alzheimer’s exhibit:

  • Increased memory loss and confusion.

  • Difficulty recognizing family and friends.

  • Difficulty learning new things and coping with new situations.

  • Trouble completing tasks with multiple steps.

  • Impulsive behavior.

  • Forgetting the names of common items.

  • Hallucinations.

  • Delusions, or paranoia.

  • Wandering

The mild to moderate stage may last between 2 and 10 years.

In the late stage, people:

  • Lose the ability to communicate.

  • May sleep more.

  • Lose weight.

  • Have trouble swallowing.

  • May be incontinent.

Severe Alzheimer’s may last between 1 and 5 years.

What is vascular dementia?

​​​​​​​While Alzheimer’s disease is the most common type of dementia, the second most common type of dementia is vascular dementia. Vascular dementia is associated with problems in the circulation of blood to the brain (cerebrovascular disease). Risk factors for this type of dementia include:

  • High blood pressure.

  • Diabetes mellitus.

  • High cholesterol.

  • History of transient ischemic attacks (TIA).

  • Heart rhythm abnormalities.

  • Evidence of disease in arteries elsewhere in the body.

What is mild cognitive impairment?

​​​​​​​An individual with mild cognitive impairment, or MCI, is able to take care of themselves and go about their normal daily activities, but they have subtle problems with memory and thinking. Some signs of MCI are losing things often, forgetting appointments, and having trouble finding the right words to say. MCI can be an early sign of Alzheimer’s disease—but not everyone with MCI will develop Alzheimer’s.

How can one recognize Alzheimer's disease from normal memory loss or ordinary forgetfulness?

​​​​​​​Everyone experiences memory lapses and forgetfulness from time to time and some decline in memory ability is a normal part of aging. For example, as an individual approaches middle age, his or her ability to recall newly learned information, such as recalling people’s names or specific words, may begin to slip. These memory problems do not get worse over short periods of time and do not interfere much with the ability to do daily activities. People may compensate for these normal memory changes by repeatedly going over things to be remembered, linking them in their mind with something already well known, or keeping lists of things to do. In contrast, the memory loss in Alzheimer's disease is much greater than expected for age. The memory lapses are more frequent and severe and interfere with the ability to manage daily activities.

Are there warning signs for Alzheimer's disease?

​​​​​​​Yes. See below. ​​​​​​​

What is typically the first sign?

Memory Loss That Affects Day-to-Day Function.

It is normal to occasionally forget appointments or phone numbers. However, a person with Alzheimer's disease may forget things more often and not remember them later. The disease prevents the person from making new memories. Memories of things from long ago often remain after the ability to learn new information is lost.

Difficulty Performing Familiar Task.

Busy people can be so distracted from time to time that they may forget what they are doing. For example, one may forget to serve the vegetables during dinner, but will remember to serve them at the end of the meal. A person with Alzheimer's disease may be unable to prepare any part of a meal or forget they ate it.

Problems With Language.

Everyone has trouble finding the right words sometimes, but a person with Alzheimer's disease may forget simple words or substitute the wrong words, making his or her sentences difficult to understand. The conversation of a person with Alzheimer's disease may wander excessively.

Disorientation of Time and Place.

It is normal to forget the day of the week or your destination-for a moment. But a person with Alzheimer's disease can have persistent problems remembering the date, day of the week, or time. They may have more trouble finding their way while driving and may occasionally get lost.

Poor or Decreased Judgment.

People may sometimes put off going to the doctor if they have an infection but eventually will seek medical attention. A person with Alzheimer's disease may not recognize the need for a doctor at all. Another example of poor judgment is that a person with Alzheimer's disease may dress inappropriately, wearing heavy clothing on a hot day, or two shirts. People with Alzheimer's disease may become distracted and unsafe while doing routine activities such as cooking or driving.

Problems with Abstract Thinking.

Trouble balancing a checkbook may be an early warning of a more serious problem.

Misplacing Things.

We all misplace things from time to time. Frequently misplacing items may indicate an underlying memory disorder. Later in the illness, a person with Alzheimer's disease may put things in inappropriate places: an iron in the freezer or a watch in the sugar bowl and forget that they put them there. They may also accuse others of stealing when they are unable to find things they need.

Changes in Mood or Behavior.

Everyone becomes sad or moody from time to time. Depression may be the first sign of an underlying memory disorder in an older person. Someone with Alzheimer's disease can exhibit a wide range of mood or behavioral changes. For example, they may display rapid mood swings - from calm to tears to anger - for no apparent reason, or become abnormally irritable, depressed, or agitated. They may have changes in their eating, sleeping, and hygiene and may engage in repetitive purposeless behaviors such as rummaging through closets and drawers.

Changes in Personality.

People's personalities can change somewhat with age. But a person with Alzheimer's disease can change dramatically, becoming, suspicious or withdrawn. Changes may also include apathy or indifference, fearfulness or anxiety, or acting inappropriately.

Loss of Initiative/Apathy.

It is normal to lose interest and motivation in housework, business activities, or social obligations, but most people regain their initiative. A person with Alzheimer's disease may become very passive and require cues and prompting to become involved in daily activities. The symptoms of apathy are sometimes not distressing to the patient but can be very disturbing for the caregiver and family.


Donald S. Marks, M.D., P.C. -- 45 Resnik Road, Suite 205 -- Plymouth, MA, 02360

Tel: (508) 746-5060   Fax: (508) 746-8060