I am frequently asked what the difference is between memory
changes associated with normal aging and that related to
Alzheimer’s disease (AD). First, the memory changes associated
with normal aging are not a disease. The typical pattern of
memory change with advanced age is a deficit in retrieval. A
healthy older brain can encode information because the
hippocampus is relatively healthy. This permits new information
to be encoded. The older adult has some difficulty retrieving
that new information, but with cues and prompts they retrieve
the information as well as those in their thirties. In contrast,
a brain with AD has a damaged hippocampus that prevents new
information from being encoded. This means that new learning
does not take place and that cures and prompts do not help
because the information is not there to be prompted. In general,
a healthy older adult encodes new information, but needs some
help in retrieving what has been encoded. A brain with AD does
not encode new information and therefore cues