Question about Neurons

[Perkins]

Hello!

I have a question from a passage on neurons.

A TPR Science workbook question said:

Temperature receptors are phasic. A woman places her right hand in hot water and her left hand in cold water for three minutes. Both hands are then placed in lukewarm water. She will feel:

I. heat with the right hand
II. heat with the left hand
III. lukewarm temperature with both hands

A. I only
B. II only
C. III only
D. I and II only

The relevant part of the accompanying passage was:

“Sensory receptors adapt at various rates. At one end of this spectrum are cells that adapt almost instantly, known as phasic. Phasic receptors do not fire at a rate proportional to the stimulus and return to its basal firing rate almost immediately after the onset of stimulation, even while the stimulus continues. In this case, stimulus intensity may be communicated by the number of receptors firing or the firing of receptors with different sensitivities. Removal of the stimulus causes phasic cells’ firing rates to transiently drop below the basal level, until adaptation to the removal has taken place.”

I was wondering why the answer is not III only?
I can see where II is right since it makes sense intuitively. But if there was a choice that said II and III I would have probably gone for it and gotten the question wrong.

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[ModusProbandi]

I chose II.

III wouldn't make any sense. What she feels is not necessarily a reflection of what reality is. There is a firing rate shift in opposite directions for both hands when she places them into the lukewarm tub, hence both won't feel lukewarm. She will feel cold with the right hand.

 

[golgiapparatus88]

I tried to think of experiencing thing myself. If my feet are freezing and i get into a hot shower (or the occasional bath), the mildly warm water will feel 100x hotter than it really is. Or think of jumping into a hot tub after being in a cold pool...or a cold pool after time in a hot tub. The temperature change is exaggerated tremendously.

 

[Trisphorin]

I don't think II and III can be right at the same time because they clearly make the distinction between feeling the heat and just feeling lukewarm.
On a side note, what should the right hand feel? lukewarm or feel a little bit cooler?

 

[cartman1980]

On a side note, what should the right hand feel? lukewarm or feel a little bit cooler?

perhaps right hand would feel the difference between hot & lukewarm == slightly lower/cooler than hot?

 

[ilovemcat]

If you want my honest opinion, I think this question is bogus.