Brief Answer:
there are different presentations.

Detailed Answer:
Hi...
Thanks for writing...i have understood your concerns...

There are different types of dementias..

The most common type is alzheimers dementia..

Initial Symptoms are mostly forgetfullness..Forgeting things after placing at one place..forgeting recent events..Forgeting familiar faces..

There are problems with language also.there word finding difficulty..called as lexical anomia...difficulty in handling complex activity, planning, organizing.

Disorientation to time,place developes...forgets ways towards home if goes outside home.

Gradually symptoms became severe and fearfullness, suspicious behavior appears..may become sad..cry..recall past events....recall persons from the past..mentions people died long back...

There is another form of dementia..frontotemporal dementia.its one type is semantic dementia..in which person has difficulty in understanding the meaning of the word..so he can not recognize the asked objest from the many similar placed together..you can read more about this from internet..

Another form is primary progressive non fluent aphasia..

these kind of language problems can occur with certain infarcts involving particular region of the brain..

So I feel that if person has change in behavior from the previous..and started forgeting something..problems with language are there..

Geriatric psychiatry consultation shud be done and proper neuropsychological evaluation shud be done..

I hope this will answer your query..best of luck..if you have further query feel free to ask..

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