Wednesday, July 25, 2007

Scrambled brain

Chemotherapy continues to wreak havoc with my memory. But the scientist in me has been interested to discover some clues about how memory works.

I've known since my first round of chemotherapy in 2004 that the drugs interfere with my mental function just as much as they produce the usual bodily problems like nausea and diarrhea. On bad days especially I have trouble forming new memories, which is a merciful form of amnesia. But on those days I also have trouble recalling events from good days in the past. That's rather inconvenient since I'm currently on chemo two weeks per month and it's hard to get any work done or keep up with everyday tasks while I have Swiss cheese in my head.

Some of the memories return when I go off of chemo, but many seemed to be lost permanently. However, I have discovered that associated senses can bring back past events. A familiar smell or returning to a particular place can release a flood of related memories. So it's not always a loss of the memory from my brain but a disruption in my ability to access that information at will. I recently learned more about this phenomenon due to the assortment of medications that I take along with cancer treatment.

My Xeloda chemotherapy gives me mild to moderate nausea and I haven't found a good medication to alleviate it. I have medications that work great for severe nausea, but they have side effects like drowsiness, constipation, or unpleasant taste, so I try to avoid them when my nausea is milder. One medication that I sometimes use is Marinol which is synthetic THC, the active chemical in marijuana. It sometimes helps suppress the nausea and give me the munchies so that I can enjoy a good meal. But for me it takes a couple hours to kick in, it doesn't always work, and when it does work it can make me feel a little goofy. Since my main goal is to be able to perform and enjoy my usual activities, most of which are cerebral, I avoid Marinol except on the worst days when I would be debilitated by nausea otherwise.

I thought that maybe the reason I wasn't getting consistent relief from Marinol was that I was taking too low of a dose. The pills are 5 mg and the directions are to take one every 2 to 4 hours for up to 30 mg per day. I had only ever taken a single pill in a day. So on a bad day last week when the first pill didn't have a noticeable effect after two hours I went ahead and took a second one.

Finally my appetite improved and I made myself a nice dinner. But two hours later, when I thought that the first pill should be wearing off, something strange happened. I was playing a video game online and I started having trouble remembering what I was doing. I accidently made a move against my teammate because I forgot he wasn't my opponent.

Then over the next half hour the confusion increased. I kept realizing that I was playing a game as if it were something that I didn't previously know: "Oh yeah, I'm playing Starcraft. I guess I better make a move. Oh yeah, I'm playing Starcraft. I guess I better make a move. Oh yeah, I'm playing Starcraft...."

I had just enough presence of mind to realize that I should probably get off the computer and go lie down on the couch. I think that I won the game, but I can't remember exactly how. For the next few hours I watched movies on TV that I've seen a thousand times before: Saving Private Ryan, Star Wars, etc. But I kept noticing scenes as if I had never seen them. My appetite was better, but I was afraid to eat since I couldn't remember whether I had already eaten and didn't want to get over full.

I started to recall very old memories from my childhood and high school days. I experienced a strange sensation of time — I kept thinking that my present state of watching movies on the couch was also a memory. I couldn't distinguish which memories were closer to the present; they all seemed equally real and relevant to me. It was only intellectually that I could reason that it must be whichever memories in which I was oldest that belonged to the present.

I managed to keep myself planted on the couch for several hours and then go to bed. At least I think I did. My main thoughts at the time were: "If this is how it feels to smoke marijuana then I don't see the attraction" and "Taking two Marinols is something to avoid in the future."

I felt very confused the next day. The newly refreshed memories of my childhood were in my head and I still didn't have an innate sense of what was past and what was present. Ironically, even though I'm going through treatment for cancer, this is actually one of the happier eras in my life. It's disconcerting to feel that I might still be going through the hell of high school and the turbulence of early adulthood.

A week later I am getting a little more convinced that July 2007 is the present. With a few days break from chemo I managed to get my brain back in gear and get some work done. I have also realized that the episode reveals that many memories that I thought were lost due to time and chemotherapy are still stored in there somewhere and await rediscovery.

1 comment:

Anonymous said...

I got linked here from your post on Slashdot.

You have to realise Marinol is not the same as smoking cannabis.
"Some patients accustomed to inhaling just enough cannabis smoke to manage symptoms have complained of too-intense intoxication from Marinol's predetermined dosages"

I know what it is too be too high, and it sucks. But no permanent damage comes from it (at least from cannabis, I don't know about Dronabinol). All I had to do was goto sleep, and then I woke up feeling far less high and in a more comfortable situation.