From Carrie Hill, PhD,
Your Guide to Alzheimer's Disease.
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Definition: The storage and retrieval of information.

In order for memory to work properly, facts, experiences, and understandings must be stored properly before they can be accessed later. In Alzheimer's disease, some people have difficulty storing information; others have trouble retrieving it; still others cannot complete either task.

Memory is often divided into:

• Short-term memory -- refers to more recent events, experiences, and information
• Long-term memory -- deals with things from long ago

Alzheimer's disease tends to compromise short-term memory more significantly than long-term memory.

Memory can also be categorized as procedural (remembering how to do things), semantic (remembering concepts and meanings), and episodic (remembering experiences, such as where you left your purse or who your teacher was for freshman algebra).

Minor memory problems can be due to stress, distraction, or fatigue. More serious memory problems may signal a disease such as Alzheimer's.