Sunday, November 18, 2007

Transient Global Amnesia (TGA)

For the third time since spring, my Mom experienced TGA. She was sleeping deeply when I arrived at the nursing home; attempts to rouse her for lunch were unsuccessful. I sat reading by her bedside until she started to stir. As she came to, I chatted with her idly about the events of my day. She looked at me with no particular alarm or recognition; her first words several minutes later were "Who are you?".

As the hospice social worker put him, I am 'letting go of letting go,' so I've long ceased concluding rapidly that 'this is it,' call the family, she's on her way out. Instead, I chatted on, casually reorienting her, none of which stuck.

So which parts of her brain were out of blood? Studies using fMRI and PET scanning, both of which are functional scans which indicate what part of the brain is actively metabolizing sugar and receiving blood flow, indicate that brain areas involved in memory function are short on blood during TGA. Specifically, the thalamus, amygdala, and hippocampus are affected. The amygdala is also involved in emotional arousal, and its hypoxic state may have explained why she did not demonstrate the sort of alarm that you'd think someone would feel about coming to in a world that made no sense.

6 comments:

janeywan said...

My we do have to much in common right now.

Dad had a trip to the hospital wed or was it thurs for a fainting spell, low BP. Seems he has Shy-Drager syndrome as a result of his meds.

Jean said...

Oh, it's a tough and long road to travel.Thinking of you.

Fran said...

Lipitor, a statin (cholesterol lowering) drug, can cause TGA (transient global amnesia). Actually, any of the statin drugs can cause TGA, due to CoQ10 deficiency. Dr Duane Graveline, a former NASA astronaut, experienced TGA and penned two books, most recently - 'Statin Drugs - Side Effects and the Misguided War on Cholesterol'.

Also, Dr Beatrice Golomb of UCSD conducts an ongoing study of those experiencing adverse effects of statin drugs.

So if your Mom is taking any of the statin drugs, that may be the cause for her 'unexplained' TGA.

Fran

Laura said...

My mother had TGA for about 48 hours a few years ago due to uncontrolled high blood pressure. It was the scariest thing of my life. She slowly got back to normal, but then she couldn't remember anything from the previous 6 weeks or so. Her long-term memory was affected, too. I had to explain to her how her parents and other family members had died over the last few decades. Her blood pressure is now controlled by meds and this hasn't happened again, thank God.

I'm praying for you and your mother. The scariest moment of my life was when my momma didn't know my name. I am so sorry.

Femail doc said...

JW: I know we're traveling this same hard road that children do when they have the blessing of having their parents live into old age. Sounds, from your latest post, like things are a bit lighter for your dad; hope that keeps up.

Jean: Thanks for your thoughts; you certainly know a tough long road when you see one. Good thoughts back at you through this holiday season.

Fran: Never knew that about Lipitor. While my mom does not take statins, this is an important fact for me to know. Thanks for sharing.

Laura: I so relate to your last line; that first time she didn't know who I was easily rated as one of the scariest of my life too. By the third episode, I had the comforting experience of knowing that it would pass. I always appreciate your prayers, and the personal stories you share.

Mauigirl said...

A friend of mine's husband, who is a chemist, recently had a dangerous accident where chemicals blew up very close to his face. He's OK after some plastic surgery but about a month after the event he had transient amnesia. He woke up and didn't know where he was at all for about 5 minutes. It was very scary to him and he's going in for a brain scan.

I guess there are a variety of things that can happen to the brain to cause these things. I'm so sorry your mom continues to have these episodes; I know how hard it must be for you to go through it with her.