Undiagnosed Problem/Question

[pmwatts]

I have an aunt who is in her late 60's, whose family thought she was suffering from dementia/Alzheimers, but the doctors say no. She is exhibiting inappropriate responses to things - like starting to giggle/laugh before she tells a joke and laughing all the way through the telling, even when it's not funny; talking about sex at inappropriate times when no-one else is talking about it or interupting totally unrelated conversations to talk about it or laughing during conversations that are not funny - like if someone is talking about car problems or health problems - she laughs. Does anyone know what might be causing this?

[Mark]

What sort of doctors have you taken your aunt to see? The symptoms you describe sound like they could possibly be aspects of frontal lobe disinhibition. the frontal lobes are the seat of judgment in the brain, and also the "brakes" which allow you to inhibit impulses that are not socially appropriate. If something is happening to the frontal brain, symptoms of the variety you describe can occur. You may want to have your aunt evaluated by a neuropsychologist who can perform testing which is able to detect subtle functional problems when an MRI cannot yet see anything. This isn't cheap testing, but it might be worth doing. It could be drug abuse too.

[reasonablybored]

my greatgrandpa was like this right before he died. he didn't have alzheimer's either. the nurses at the home he was in were complaining about it but we didn't know what to do.

we just figured it was his mind going because of all the duress his body was going through (liver failure).

[Natalie]

Your aunt needs to evaluated by a physician who specializes in geriatrics (the assessment and treatment of older people). There are all sorts of things that can go on that can make an older adult "act funny." I assume that the reason why you are concerned about your aunt's behavior is that this is a change for her and she didn't previously behave this way.
Potential problems can be caused by
Overmedication or medications that are interacting with each other in a bad way
Physical illnesses or problems (of a medical nature such as vitamin deficiencies, hormone imbalances, etc, etc)
Undiagnosed mental illnesses

The physician needs to start with a complete physical and lab tests first, to make sure rule out medical conditions. It would be best if someone who knows what's going on can go with your aunt to the doctor to explain the behavior changes if she is unaware of them, or does not know how to describe them.

If no medical condition is causing the problem, then get a referral to a mental health clinician who specializes in geriatrics (hopefully, the physician has a list of names that he or she can recommend). A licensed clinical psychologist is probably the best type of professional to consult, as they have more training and experience in assessment/diagnosis. That clinician (in consultation with other professionals, perhaps a neurologist, if necessary) should be able to help get a handle on what's going on.

FYI- There is type of dementia called Pick's Disease (or Pick's dementia) that can cause dramatic personality changes. This disease attacks the frontal part of the brain (that Dr. Dombeck described in his reply). This could very well be what is happening.