Clunking someone with a bat = knock out?

[Pengwuino]

ya know what i always wondered (in the last 5 minutes)... why do people get knocked out when they are hit in the head with a bat? Like, what happens biologically...

And is it possible to hit someone in the back (ie in the movies) and knock them out? This stuff always confuses me :)

Whats truth, and what's fiction, bum bum bum...

oh and when i say bat, i just mean anything hard :P

 

[Entropy]

I know I got hit with a bat right upside the head (with no helmet) when I was eight by this big fat kid while playing catcher. I didn't get knocked out, it just hurt like hell.

 

[TheStatutoryApe]

Head Trauma
http://www.trauma.org/thoracic/bluntthoracic.html

These are a bit extreme but I'm assuming that any blunt injury that results in unconsciousness are at least mild forms of trauma.

 

[zoobyshoe]

ya know what i always wondered (in the last 5 minutes)... why do people get knocked out when they are hit in the head with a bat? Like, what happens biologically...

Basically, there is an important part of the brain called the thalamus which seems to be a kind of Grand Central Station for imput to the brain from the senses and is also a kind of pivot point for consciousness. It is extremely sensitive to disruption. In one book about the brain I read it said that directly touching it with a feather would render someone unconscious. Fortunately it is located right about at the center of the brain where it's protected from direct injury. In any case where a person is "knocked out" their brain has been distorted enough to impinge on the thalamus.

Even if a person is lucky enough to get "knocked out" without their skull being damaged the distortion of the brain required to cause this to happen is pretty radical and I wouldn't be surprised if even one instance of this causes widespread microscopic tearing of brain tissue. I saw an x-ray taken of a boxer in the process of getting hit in the head (a special set up done in a lab with volunteers) and the distortion of his brain was unbelievable to me. The brain is inert as a material mass and tries to stay where it is when the impact to the skull occurs.

 

[cotarded]

I'm almost more interested in what part of the brain does the bootstrapping, and reinitiates activity. Or is that process centralized at all? I suppose it could be every neuron for itself, with some firing into the dark whilst their audience still sleeps, and others listening when the other end of the line is still cut. Any further illumination zoobyshoe?

Also, anyone understand exactly why the thalamus is so critical? Does it provide a constant excitatory input to activated portions of the brain, or does it just facilitate communication between distant portions of the brain, without which the circuits fail to be able to perform meaningful computation? I'm trying to avoid the reasoning that it is necessary for consciousness, which is necessary for all those calculations to take place, because that's a whole other can of worms in itself, and I'm pretty sure this can be separated from that issue.

Also, zoobyshoe, do you remember where you saw that x-ray? I'd like to check that out.

lates,
cotarded

 

[zoobyshoe]

I'm almost more interested in what part of the brain does the bootstrapping, and reinitiates activity.

Possibly the cells in the reticular formation of the brainstem that control the thalamus' level of activity.

I'm trying to avoid the reasoning that it is necessary for consciousness, which is necessary for all those calculations to take place, because that's a whole other can of worms in itself, and I'm pretty sure this can be separated from that issue.

Well, there is no doubt it is necessary, which is known from the phenomena of absence seizures. These are limited to the thalamo-cortical complex. During an absence seizure the person completely loses consciousness, and just about nothing else. To them, the couple/three seconds these seizures last are edited out of their lives never to be recovered: they see the world jump forward like a film missing many frames.

Also, zoobyshoe, do you remember where you saw that x-ray? I'd like to check that out.

No, I don't remember. It was in an old book. Possibly 1960's.

 

[cotarded]

Thanks for the RF tip. I'll be looking further into it now.

Well, there is no doubt it is necessary, which is known from the phenomena of absence seizures. These are limited to the thalamo-cortical complex. During an absence seizure the person completely loses consciousness, and just about nothing else. To them, the couple/three seconds these seizures last are edited out of their lives never to be recovered: they see the world jump forward like a film missing many frames.

I'm sorry, I wasn't clear. I didn't mean to give the impression I was disputing its necessity for consciousness, I just meant I wanted to avoid the circular logic of "Thalamus is critical for functionality because it is necessary for consciousness (which is only outwardly discernable through functionality)" - unless you actually assume that the thalamus is the substrate of consciousness (a position I think neither of us is ready to assume). So I leave the question open:
"Does it provide a constant excitatory input to activated portions of the brain, or does it just facilitate communication between distant portions of the brain, without which the circuits fail to be able to perform meaningful computation?" Or perhaps the whole thing is better put, what does the thalamus do, without which the higher systems of the brain cease to function?

lates,
cotarded.

 

[zoobyshoe]

Or perhaps the whole thing is better put, what does the thalamus do, without which the higher systems of the brain cease to function?

I don't think anyone knows, but I think with a little reading you could easily find out a lot more about the thalamus than I know. The parts of it dedicated to "consciousness" are actually a small percentage of the whole mass. These are the "lenticular formations". The rest of the thalami do all kinds of coordinating of imput from the senses. One thing I do know that may be of interest is that a certain kind of lobotomy that used to be performed involved simply severing the connections between the thalamus and the part of the frontal lobes they wanted to criple. That was as good as removing that part of the lobe.

I'll dig up an interview with a neurologist who feels the frequency of the oscillations of cells in the thalamus are the critical element in its role in consciousness. It's an easy read. Hypnagogue may have leads to papers dedicated to trying to address your specific question

edit: Here it is:

http://www.pbs.org/wgbh/nova/mind/electric2.html