THERMORECEPTOR PHYSIOLOGY 
DR. HENSEL: Oh, the vibration was quite small, but a few very 
sensitive mechano receptors could sometimes be excited by the 
vibration. 
DR. LIM: During cooling, you have a curve coming down, but it 
never reached the zero line. At the end of the cooling period, what 
were the impulses per second? 
DR. HENSEL: The maximum frequency of a cold fiber at con- 
stant temperature is about 10 impulses/sec. 
DR. LIM: I noticed that your time scale is about a minute or so. 
If you prolong it for ten minutes, what is the effect? 
DR. HENSEL: I would say that the final value is reached after 
about one minute. Thereafter the impulse frequency will remain 
constant as long as we are able to record from a single fiber, at 
least for several hours. 
DR. LIM: But still above zero? 
DR. HENSEL: Yes, for the whole time. 
DR. FREEMAN: What was the relation between accommodation 
and sensitivity or the sensations of the subjects with regard to 
intensity? 
DR. HENSEL: Generally, the impulse discharge is more sens- 
itive than the conscious sensation. For example, a skin temperature 
of 34 C is absolutely indifferent for the subject, but there is a 
considerable discharge of the cold fibers. 
DR. FREEMAN: Does the peak of sensitivity coincide with the 
peak of discharge? 
DR. HENSEL: Yes, roughly. It is difficult tomeasure this very 
accurately in a subjective way. 
DR. FREEMAN: Do you ever get a paradoxical sensitivity of 
warmth associated with this accommodation process? 
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