JFK's Head Snap and the Implausible Jet-Effect and Neurospasm Theories

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Author Topic: JFK's Head Snap and the Implausible Jet-Effect and Neurospasm Theories  (Read 131464 times)

Offline Tim Nickerson

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Oh boy oh boy. Apparently you do not know what "decerebrate" means and what a "decerebrate reaction" is. Apparently you don't understand that when Sturdivan talked about the beginning and end (terminus) of the "decerebrate reaction," he was referring to the neuromuscular reaction. Instead, you're assuming that when Sturdivan said "and that takes places about a second after the shot," he was only talking about half of the actions he had just described, because you think that the decerebrate reaction is separate from the neuromuscular reaction. First, let's read Sturdivan again:

Now let's see what "decerebrate" means:

That is exactly the reaction that Sturdivan describes seeing in the 2400 fps film, and he calls it "the neuromuscular reaction that I described," which could only refer to the description of the real-time film:

Sturdivan knew what "decerebrate reaction" means, and he used it synonymously with "neuromuscular reaction." His syntax could have been a little clearer, but if you know what "decerebrate" means, you can see he was not saying that the decerebrate reaction was different from the neuromuscular reaction--he knew enough not to make such a fundamental error.

Now that we have that point cleared up, you need to deal with his observation that in "real time" the neuromuscular reaction began about 1000 milliseconds after bullet impact.

Sturdivan may have been using "decerebrate reaction" synonymously with "neuromuscular reaction" ,but you err in assuming that he was using "decerebrate rigidity" synonymously with "neuromuscular reaction". He used "terminus of the decerebrate reaction" synonymously with "decerebrate rigidity".
« Last Edit: June 30, 2020, 11:11:21 PM by Tim Nickerson »

Offline Joe Elliott

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Amazing. For the past week or so you have repeatedly said that JFK's head began to move backward 55 milliseconds after bullet impact. I trust I don't need to quote you to yourself. But, well, now that you realize you need that movement to start later--much later--to allow for the mere possibility that it was caused by a neurospasm, you suddenly decide that it might have begun 82 seconds after impact, an increase of 48%.

I have no need to increase it. The goat starts moving after 40 milliseconds. I only meant to clarify that 55 milliseconds is an approximate time. I don’t know if it was 49 milliseconds, 64 milliseconds or 82 milliseconds. I never meant the 55 milliseconds to be some sort of precise estimate. Anymore than I mean 82 milliseconds is a precise estimate.

Offline Michael T. Griffith

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What does Mr. Sturdivan mean when he says:

Don’t change the subject. Don’t quote a different portion of the testimony.

Don't change the subject?! You erroneously assumed that Sturdivan was describing two separate reactions in the real-time film because you didn't know what "decerebrate" meant! But now you want to ignore that gaffe and ignore that Sturdivan said the neuromusuclar reaction occurred in about 1000 milliseconds in real time.

Just give me your interpretation of this sentence. My interpretation is that 40 milliseconds after the impact of the bullet, the goat’s body starts to move.

Then please explain what Sturdivan meant when he stated in pretty plain English that in "real time" the reaction took about 1,000 milliseconds. Is "real time" really not real time? Did Sturdivan just egregiously misspeak?




Offline Tim Nickerson

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No. I am not measuring time to the nearest frame, but to the nearest tenth of a frame. Each tenth of a frame is roughly 5 milliseconds long.

z-312.0 is when the shutter opens for frame 312. Roughly 27 milliseconds later the shutter closes at z-312.5. Frame z-312 shows images from time z-312.0 through z-312.5.

I believe the bullet struck at z-312.5, or there abouts, right when the shutter closed or very shortly after. Below is a possible, approximate, time scale. Basically, my best very rough estimate:

Vis    Time    Time
able    in      in
        sec.    Zap         Event
----  -----    -------     ---------------
       0.000   z-312.5   Shutter closes.
       0.000   z-312.5   Bullet impact.
       0.001   z-312.5   Bullet leaves head,
                                momentum has been deposited into head,
                                the head starts moving at a steady speed forward.
       0.027   z-313.0   Shutter opens.
vis   0.027   z-313.0       Head is now 1 inch in front of z-312 position, same steady speed
vis   0.055   z-313.5       Head is now 2 inches in front of z-312 position, same steady speed
       0.055   z-313.5   Shutter closes.
       0.077   z-314.0   Shutter opens.
vis   0.082   z-314.1   Neuromuscular spasm commences,
vis                                 Head starts moving back, initially slowly.
vis   0.110   z-314.5   Head is now 1.5 inches ahead of 312.5 position.
       0.110   z-314.5   Shutter closes.

“vis” refers to events that may be visible, because the shutter was open.

Again, this is not to represent exact locations. I don’t have the timing down to the nearest 5 milliseconds. Just a possible scenario consistent with what the Zapruder film shows and William Hoffman’s data.

In this scenario, the neuromuscular spasm started 82 milliseconds after the bullet impact. The real time  of reaction could be a little more, or less.

Thanks for clarifying.

I think that we have been wrongly assuming that the start of the backward head movement was the initiation of the neuromuscular spasm. That backward motion was from the jet effect and the neuromuscular reaction initiated a couple of frames later.

Offline Tim Nickerson

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Then please explain what Sturdivan meant when he stated in pretty plain English that in "real time" the reaction took about 1,000 milliseconds. Is "real time" really not real time? Did Sturdivan just egregiously misspeak?

From "the time that the bullet struck" to the "terminus of the decerebrate reaction" took about 1,000 milliseconds. That's what Sturdivan was saying.
« Last Edit: June 30, 2020, 11:27:22 PM by Tim Nickerson »

Offline Tim Nickerson

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First, let's read Sturdivan again:

"About one-tenth of a second after the shot, the goat goes into what one Biophysics Lab colleague, Bob Clare, described as a "swan dive", which results in him leaping out of the back part of the sling." -- page 165, The JFK Myths: A Scientific Investigation of the Kennedy Assassination, by Larry Sturdivan

https://www.amazon.com/JFK-Myths-Scientific-Investigation-Assassination/dp/1557788472

Offline Joe Elliott

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Actually, I don’t think Mr. Sturdivan made an ambiguous statement.

Quote
This is a real time. First, we will observe the neuromuscular reaction, the goat will collapse then, and by the wiggling of his tail and the tenseness of the muscles we will see what I think has sometimes been called the decerebrate rigidity, and that takes place about a second after the shot and then slowly dissipates and you will see the goat slump, obviously dead.

What is the definition of “decerebrate rigidity”?

I looked it up and it is as follows:

decerebrate rigidity a posture found in those with lesions of the upper part of the brainstem. . .

“decerebrate rigidity” is a posture. It is a posture that one assumes, as a result of damage of the brainstem, or severe bilateral lesions of the cerebrum.

When did the goat assume this posture? One second after impact. Not, it started to assume this posture after one second. It means it had reached this posture, with the limbs sprayed out, one second after impact.
« Last Edit: June 30, 2020, 11:59:00 PM by Joe Elliott »