Updated May 11, 2015.

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What Are the 4 A's?

The 4 A's are four words that describe some of the main symptoms of Alzheimer's disease. The A's represent the following:

Amnesia:

Amnesia refers to memory loss and is often the most easily visible and common sign of Alzheimer's disease. Memory loss in Alzheimer's disease typically begins with the short-term memory and progresses to a decline in long-term memory.

• How Does Alzheimer's Affect Short-Term Memory?

• When Does Alzheimer's Affect Long-Term Memory?

Aphasia:

Aphasia is a term used to describe impaired communication. Aphasia may be classified as expressive aphasia, where someone is unable to find the right words or may say them incorrectly, or receptive aphasia, where the ability to understand, receive and interpret language is impaired. Aphasia is commonly thought of as the impairment of speech and language, but it also can include the ability to read and write.

• When Should You Worry if You Can't Find the Right Word?
• What Is Primary Progressive Aphasia? Is It Similar to Alzheimer's?
• Reader's Question: Will I Still Be Able to Read as My Dementia Progresses?
• How to Talk with Someone Who Has Dementia

Apraxia:

Apraxia is a deficit in voluntary motor skills. As Alzheimer's progresses, the ability to perform certain activities of daily living such as bathing and getting dressed might decline. Activities such as walking and eating become more difficult in the late stages of Alzheimer's disease.

• Successful Suggestions for Bathing Someone with Dementia

• Why Do People with Dementia Fall?
• Physical Declines that Accompany Dementia
• Practical Hydration Strategies in Later Alzheimer's Disease

Agnosia:

Agnosia is the impairment of the ability to receive or correctly understand information from the senses of hearing, smell, taste, touch and vision. For example, people with Alzheimer's disease often are less able to identify smells, or understand the feeling of a full bladder. They also might not be able to recognize loved ones as the disease progresses.

• How to Cope when Your Loved One Doesn't Recognize You
• Does Alzheimer's Affect the Sense of Smell?

<sub>Sources:

Alzheimer Europe. Main characteristics: August 2009. Alzheimer's disease.http://www.alzheimer-europe.org/EN/Dementia/Alzheimer-s-disease/Main-characteristics-of-Alzheimer-s-disease/Apraxia-Aphasia-Agnosia#fragment-2

Alzheimer's Foundation of America. Accessed October 31, 2014. About Alzheimer's. http://www.alzfdn.org/AboutAlzheimers/symptoms.html

Alzheimer's Foundation of America. Accessed October 31, 2014. National Memory Screening. http://nationalmemoryscreening.org/alzheimers-symptoms.php

US Department of Health and Human Services. National Institute on Aging. Accessed October 31, 2014. About Alzheimer's Disease: Symptoms. http://www.nia.nih.gov/alzheimers/topics/symptoms?utm_source=ad_fact_sheet&utm_medium=web&utm_content=symptoms&utm_campaign=top_promo_box

US Department of Health and Human Services. October 2008. National Institute on Deafness and Other Communication Disorders. Aphasia. http://www.nidcd.nih.gov/health/voice/pages/aphasia.aspx</sub>