[Pavel Urbanek]

Pavel Urbanek  asked the Naked Scientists:
   
Hello Redi and Chris  

Once via internet I have stumbled on your programme, probably as most of your listeners I wanted to see more of the _naked_ scientists.

Now I know that you are not naked L, but the programme is nevertheless very enjoyable and interesting. I cannot listen live, but do download a few programmes at a time and then listen to them while driving.       

On the 16th September a question popped up about yawning. I have a follow up question: While studying at UCT, years back when I was still young and beautiful, I often visited there a friend, a lady with medical background. We have talked about many interesting subjects (mostly themes which were for me somewhat new. Not esoteric but perhaps going in that direction). Often I needed lots of power to keep the *concentration *staying up with the subject and this made me *yawn*. I was sort of ashamed yawning but she almost happily said it is because I am really concentrating on the subject.   Is there any connection to what you mentioned in your programme? In other words: was my brain "overheating"?       

Kind regards,   Pavel Urbanek        

What do you think?

[Airthumbs]

Based on what has been written here I think that a possible experiment could be conducted that is quite simple and would hopefully answer the question posted above.

Do people who wear hats yawn more then people who do not?

[Devilmunkey]

All living organisms need to maintain specific temperatures in order to function correctly and efficiently. This is part of a process known as homoestasis. In humans the optimal temperature is 37.5C (I do not know the comparative temperature in farenheit).  The general activity of the body results in the production of heat (as a by-product, as no biological system is 100% efficient), and mammalian systems use a variety of processes to aleviate this excess heat; addaptation of sebacious glands in the skin to produce sweat is perhaps the most well known. Other animals use behavioural or environmental strategies to achieve this.

Failure to maitain the optimal temperature for an organism can have severe consequecies, such as hypo/hyperthermia in humans, and the denaturisation of enyzmes through heat is well documented.

Apologies for rambling somewhat. My point is that many activities may result in an increase (or decrease) in relative body temperature, and this may focus on a specific organ or area of tissue depending on its nature, but there are a wealth of bio-feedback proccesses an organism would employ (given a good state of health and favourable environment) to combat this and as such it would be unlikely to become a serious issue and would also likely be ephimeral and perhaps hard to quantifiy experimentaly.

As far as yawning goes, I have heard/read many potential explanations for this phenomena, but have not seen anything that provides more than speculation on its actual purpose (one of last years Ig Nobel awards went to a biologist who taught a tortoise to yawn, only to learn that other individuals would not copy the behaviour, it is an entertaining read if such things interest you).

[CliffordK]

What the PET scans and fMRI scans indicate is that thinking can cause local increases in blood flow and sugar consumption.  And, thus, more energy and more heat in those local areas.

In Fahrenheit, "normal" is 98.6°F, but can vary a few degrees between individuals, ambient temperature, activities, and, of course, disease states.

As far as deep concentration and yawning.  I don't know.  Sometimes I'll close my eyes when in deep thought, and zone out a bit.  But, yawning is often associated with less interest in a subject.