A form of dementia, Alzheimer's Disease is characterized by memory loss and a decline in a number of cognitive abilities caused by deterioration of certain parts of the brain. The following Four A's of Alzheimer's Disease describe the medical terms for these primary symptoms:
- Amnesia is the inability to use or retain memory, including short term and long term memory. The person may constantly repeat questions such as "Where am I?" and "Who are you?" and "When are we going to eat?" or accuse the caregiver of stealing or being an imposter. This process occurs from damage to the frontal lobes of the brain which store memory, personality, cognition, impulse control, speech, attention, rational thought, imagination and judgment.
- Agnosia is the inability to recognize or use common objects or people. The person may become lost in a familiar place because he or she doesn't recognize the items that alert us to our surroundings. He or she may confuse a fork with a spoon, a toothbrush with a hairbrush or toothpaste with shaving cream. Eventually the ability to recognize objects is lost completely. The person may also confuse a son with a husband or a father or an uncle, or a daughter may be confused with a mother or an aunt or a grandmother. This process is associated with increased damage to the frontal lobes, the occipital lobes (visual association, distance and depth perception) and the temporal lobes (language, hearing and smell) of the brain.
- Aphasia is the inability to use or understand language. The person will use the wrong word, or complete a story with phrases from another story, or provide a lengthy description of an item because he or she cannot find the right word. He or she may call family members by the wrong name, which increases the family's anxiety and concern. This word finding difficulty will increase until all language use is lost. This is associated with damage to the temporal lobes and the frontal lobes of the brain.
- Apraxia is the inability to use or coordinate purposeful muscle movement or coordination. In the early stages the person may reach for an item and miss it. He or she may have difficulty catching a ball or clapping his or her hands. The floor may appear to be moving to this person and balance becomes affected, increasing the risk for falls and injury. In time, this loss of ability to move affects the activities of daily living (sleeping, ambulating, toileting, grooming, hygiene, dressing and eating). In the end stage, the person is not able to properly chew or swallow food, increasing the risk of choking or aspiration. This is linked to damage to parietal lobes (pain, touch, temperature and pressure, sensory perception), the cortex (skilled movement) and the occipital lobes of the brain.