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Medical Brain vs. CPU

  1. Aug 10, 2005 #1
    Hello, I'm an engineering major so this could sound like a REALLLY dumb question for you guys and girls but I'm just really curious...ok here it is:

    CPU's (computers' brains) work faster when they're colder...do real brains work faster when they are in colder surroundings too?

    As I was typing the question I realized that, unless it's sick, the body's temperature is always 37 degrees C so I guess the "surrounding" temperature for the brain is always the same no matter what the outside temperature is. However, I think the question is still interesting...any input would be appreciated.
  2. jcsd
  3. Aug 11, 2005 #2
    Cooling by itself won't make CPUs work any faster unless specific steps are done to overclock the CPU (increase the CPU's clock frequency). The primary purpose of cooling a CPU (using fans, decreasing ambient temperature, active cooling) is to disspate the heat generated by the CPU.

    Cells for the most part tend to shut down and/or die when cooled too much.
  4. Aug 11, 2005 #3
    Hmmm I noticed a big difference in my computer's speed when it's hot vs. cold. I guess it could be the HD.
  5. Aug 11, 2005 #4


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    Most of your body's processes work fastest at about 37c. Enzymes/proteins work increasingly quickly with increasing temperature until about the 40c mark where they 'denature' which basically means they lose their structure and are unable to do their job. This would probably apply to post-synaptic receptors in neurones of the brain and nervous system, if I remember my college biology correctly.
  6. Aug 11, 2005 #5


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    Your computer may be dialing itself down to keep from overheating.
  7. Aug 11, 2005 #6


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    I think it would be better stated that the CPU can work faster (and/or more efficiently) when run under cooler temperatures than when hot. So even without overclocking the system, the CPU may process faster, but it would most likely be a subtle (undetectable to the normal user) increase in performance.

    As far as the brain is concerned its obviously a biological system and as stated these systems work best under 37C conditions, cooling below these temperature would only serve to slow the system down. There is the aspect of brain cooling that is associated with times of hyperthermia. Certain mammal species have vascular structures that serve to cool overly warm bolld that is going to the brain, these are called retia miribilia (or varitations on this term - rete mirable). It basically a counter-current system that apposes warm incoming blood with cooler outgoing blood and an exchange of temperature occurrs. Humans do not have these structures, however it is theorized that certain other structures such as the dura mater, cerebrospinal fluid compartments and related vasculature can effectively keep the brain cool under certain circumstances. I haven't found any rock solid, unequivocal data to suppor this, but papers do exist that speak to the subject: selective brain cooling, human brain cooling review. A Pubmed search will reveal more.

    All regions of the brain rely on proper function of enzymes/proteins, so the effects of extreme hyperthermia will be rather global and dramatic.
  8. Aug 11, 2005 #7
    CPUs do work faster when they are cooler, thats why the goal is to keep them as cool as possible...When metal gets warm there is more resistance.
  9. Aug 12, 2005 #8


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    Hi All,

    Brain is cooled, fortunately by blood supply. :wink:
  10. Aug 13, 2005 #9
    CPU speed is dictated by its clock frequency. Cooling is primarily for dissipating the heat generated so the CPU doesn't melt down. Refrigeration/extreme cooling by itself will only get you marginal and barely detectable speed increases. To get any real speed increases, you have to increase the CPU's clock frequency. Higher clock frequency means more heat generated requiring better cooling.
  11. Aug 21, 2005 #10
    The answer does not seem that simple though. As the temperature increases there is more resistance for conductors like copper metal, but for semiconductors there is LESS resistance as the temperature increases and more resistance as it gets colder (in terms of resistance, the two respond to changes in temperature exactly opposite to one another).

    The inside of a computer contains silicon chip semiconductors, whereas the current being supplied through the walls is transferred through copper metal. So while there is less resistance on the copper wire in the walls as the temperature drops, the resistance for the silicon chips inside the computer itself would increase. Not that i am an expert on this sort of thing, but I would imagine that if computer performance could be greatly improved by using a computer in settings that are as "cool as possible", big companies would use computers in freezers and operate them at temperatures less than zero degrees. It's clearly not done that way.
    Last edited: Aug 21, 2005
  12. Aug 22, 2005 #11
    Can't a body temperature of more than 104.7 degrees farenheit cause brain damage in humans?

  13. Aug 23, 2005 #12
    I don't know the exact temperature, but you are right; if the internal temperature of a person gets to be a few degrees F over 100 and the person actually lives afterwards to get back down to normal temperature, it is still highly likely that they will walk away with brain damage.

    In general for homeotherms like us, any extreme in temperature away from "normal conditions" seems like it will effect us in a negative way. This can be demonstrated by paying attention to our feelings, as it gets colder and colder we feel more and more uncomfortable and we eventually die if it gets too cold. Likewise, if it gets too hot we start to feel more and more uncomfortable and can die if it gets too hot. So I am inclined to believe the people that say that we operate best at "normal" temperatures because the moment things start to get very hot or cold, our body makes it very clear to us that it would like us to act in such a way to return to normal temperature state (by locating a heat source in cold climates or trying to cool down in hot ones) as quickly as possible. Maybe computers operate at their best between the two extremes as well?
    Last edited: Aug 23, 2005
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