Saturday, March 19, 2005

Medical opinions on Schiavo
Respectful of Otters has what I think is the definitive smack-down of those who claim that Schiavo's videos contain evidence of purposive brain function. The key passage:

So the presence of smiles, grimaces, vocalizations, and eye movements alone is not relevant to the question of whether Schiavo has retained any degree of consciousness or may benefit from therapy. They may be in part reflexive - as when she "smiles" when her cheek is stroked - and they may be completely random.

The key to the 4 minutes and 20 seconds of video is that Schiavo seems to be responding in a meaningful way to specific stimuli. All 17 experts who reference the videos take for granted that they demonstrate meaningful emotional or communicative responses. Could they really all be wrong?Oh, yes. All you need to know to illuminate the question is that the six snippets of video were selected from 4 1/2 hours of tape. As do most people with PVS, Schiavo emits random behaviors and noises. If a person gives enough commands or makes enough interaction attempts over the course of several hours, by sheer coincidence some of Schiavo's random behaviors will appear to coincide with their commands. Both the trial court and the appeals court viewed the entire 4 1/2 hour tape, and both concluded that her responses were indeed random. As the original court decision pointed out:

Dr. Hammesfahr testified that he felt that he was able to get Terry Schiavo to reproduce repeatedly to his commands. However, by the court's count, he gave 105 commands to Terry Schiavo and, at his direction, Mrs. Schindler gave an additional 6 commands. Again, by the court's count, he asked her 61 questions and Mrs. Schindler, at his direction, asked her an additional 11 questions. The court saw few actions that could be considered responsive to either those commands or those questions. The videographer focused on her hands when Dr. Hammesfahr was asking her to squeeze. While Dr. Hammesfahr testified that she squeezed his finger on command, the video would not appear to support that and his reaction on the video likewise would not appear to support that testimony.

Hammesfahr's own report makes clear that he relied on a ludicrously low standard to conclude that Schiavo's responses were purposeful:

Interestingly, some of the commands, such as close your eyes, open your eyes, etc. she tended to do several minutes after I gave her the command to do so. She had a delay in her processing of the action. However, when praised for the action, she would then continue to do the action repetitively for up to approximately 5 minutes. As we had moved on to other areas of the exam, at times she was continuing to do the previous command, then at inappropriate times since the focus of the exam had changed.

He commanded her to emit some of her known behaviors, such as closing or opening her eyes. If she did, that was a "hit" - a sign that she had obeyed the command. If she did so several minutes later, that was still a "hit," apparently no matter what else he'd asked her to do in the interim. If she continued , long after he'd moved on, that was not a sign that she was unresponsive to his subsequent commands but, instead, a sign that she was responsive to praise. Almost any response, correct or incorrect, could apparently be interpreted to signal consciousness. Hammesfahr, like Schiavo's parents, wanted to be convinced.

Terri Schiavo's case is tragic, but not medically complicated. Nothing about it suggests any room for diversity of medical or neuropsychological opinion. The "experts" who submitted affidavits appear to know little about her case beyond what they were able to glean from cherry-picked videotape segments only a few minutes in length. They recommend sophisticated neuroimaging techniques which are not relevant to the question of the feasibility of rehabilitation when the cerebral cortex is gone.

'Nuf said.

CORRECTION: The original version of this post mistakenly identified Respectful of Otters as an M.D.. The post should have read "Ph.D."


At 8:13 PM, Blogger Rivka said...

I'm actually a Ph.D. (clinical psychology). But thanks for the kind words. I agree that this really is the meat of the controversy.

At 8:13 PM, Blogger Rivka said...

I'm actually a Ph.D. (clinical psychology). But thanks for the kind words. I agree that this really is the meat of the controversy.


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