"Ronald Blue" <rcb5 at MSN.COM> wrote in article
<UPMAIL07.199702081833380330 at msn.com>...
> From: Jay Hanson
> Sent: Saturday, February 08, 1997 12:38 PM
> To: neur-sci at net.bio.net> Subject: More Co2 = less brains?
>> What are the effects on people of increased atmospheric Co2?
>> Obviously, more atmospheric Co2 means less O2 available as
> percentages of total gases. I remember reading, quite some
> time ago, that as the Co2 percentage goes up, the cognitive
> abilities of man are decreased.
>> Does anyone know of any studies in this reguard?
>> I believe you are correct. But if you have less O2 then your
> levels of CO may be higher. CO is a neurotransmitter.
> It might increase associative learning?
> Ron Blue
The actual percentage of CO2 in the atmosphere is way less than one
percent, whereas the percentage of O2 is greater than 20. Therefore, other
more serious environmental problems will come to bear before CO2 will
"crowd out" atmospheric O2.
However, that is not to say that too much CO2 is not a big deal. Excess
CO2 in the blood will acidify the blood, which will mess up the ionic
equilibrium of the body's cells (particularly potassium), including neurons
in the brain. The deranged equilibrium probably does cause cognitive
defects, if mild. However, the condition of having too much CO2 in the
blood, or hypercapnia (or hypercarbia) will lead to unconsciousness if
By the way, CO or carbon monoxide is NOT a neurotransmitter. In fact, it
is a toxin that outcompetes oxygen for binding sites on hemoglobin, thus
starving the body of oxygen. You may be thinking of NO, or nitric oxide,
which does have intercellular signalling functions.