Information Processing in the Time Domain 



339 



AtTIVi 



DERIVATIVE 



l! High Frequency Noise 



ii Rejected by Pulse 



11 Width Dis-'-criraination 



IjOW Frequency, Low Level 

 Noise Not Converted to 

 Rectangular Pulses 



Effective Response Level 



Fig. 6. Period Analysis of the Galvanic Skin Response. The first derivative of the 

 primary GSR clearly shows the accentuation of "noisy" fast components. The 

 effective response level or threshold for square wave generation "filters" out 

 slow components of insufficient amplitude. Square waves of less than one second 

 are filtered out by the "period filter" (see text). 



