抄録
A study on the galvanic skin reflex was made in ten adult females at three seasons, namely spring, summer and winter. Reflex curves were recorded simultaneously from the thenar and hypothenar regions by attaching two apparatuses of so called simple circuits and vibrator-F (5×10-7 A, 35c/s, 60Ω) of electromagnetic oscillograph using Faradic stimulation. The study was based mainly on latent and reaction times of the reflex curves. The skin temperature was measured by thermojunction at each examination.
The results are as follows:
1) The latent and reaction times were markedly prolonged in winter as compared with those in spring and in summer. In winter the mean latent and reaction times were 2, 75″ and 4, 51″ respectively as against 1, 72″ and 2, 15″ in spring and 1, 79″ and 1, 78″ in summer. 2) Findings of simultaneous recording when both index fingertips were being attached to the electrode:
Within five minutes after immersion of the right index finger into the warm water a reduction of the latent and reaction times were noted. When placed in cold water a prolongation of the latent and reaction time was observed, and in icewater no reflex was elicited although a definite reflex curve was shown in the control.
3) When stimuli were applied to the lumbar sympathetic ganglion, a similar reduction of the latent and reaction time was observed in three cats which were being warmed with electric heater.
From these findings it is considered that the seasonal difference of the galvanic skin reflex of the thenar chiefly depends on the skin temperature which is lowest in winter and highest in summer. However, the factor of seasonal adaptation of sweat gland cannot be disregarded in the causation of this difference of reflex.
4) Of ten persons in whom the examination was caned out the reflex curve of the hypothenar region was elicited in six in summer, three in spring, and none in winter.
When a limited area (about 1cm square) of the hypothenar region where electrode was attached, was heated for 30 minutes, reflex was observed in two of six tested in warm spring days, while none responded in cold winter days.
On the basis of above experiment, it may be stated that reflex of the thenar and hypothenar regions differ according to season as well as when heat is locally applied.
