User manual

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Fig. 4.4.2.4.1. Evoked Repeat PulseSweeps can not occur in an Average Loop. At arrow, the ‘Repeat
P0’ sweep button was clicked evoking the LTD stimulation which only started after 2nd Average Loop
exited. Also note that For LTD stimulation with averaging, the current and total number of sweeps evoked
is now written on the RunLine.
However, evoking Single or Repeat T0 or T1 sweeps in an Averaging Loop is fine because these do not
have a sum array and averaging is never done on them. And if you are using the Protocol Builder, only
one P0sweep and only one P1sweep is allowed in an AverageLoop – e.g. this possible bug has been
prohibited in the Protocol Builder.
4.5 Signal Averaging, Stimulus Artifact Blanking and Low-Pass
Digital Filtering
In addition to capturing and analyzing raw sweeps, the WinLTP can also do on- and off-line signal
averaging of these sweeps, blank out the stimulus artifacts if required, and low-pass filter the sweeps.
Section 4.4.1 and Fig. 4.4.1.1B have already shown you how to do signal averaging in WinLTP.
The ‘Enable Sweep Functions’ panel in the MainProtocol tabsheet (Fig. 4.5.1A, also see Fig. 3.1.2.1) is
used to set the stimulus artifact blanking and digital filtering options:
1) Stimulus Artifact Blanking enables the stimulus artifacts to be removed on either the Pulse and/or
Train Sweeps, and occurs after averaging. Stimulus Artifact Blanking cannot be performed on
Spontaneous Sweeps.
2) Low-Pass Filtering enables digital filtering on either the Pulse, Train and/or Spontaneous Sweeps,
and occurs after averaging and stimulus artifact blanking.