User manual

81
Function Keys or Run Menu items ((Sections 3.1.5 and 3.3, and Figs. 3.1.5.1 and 3.2.6). These enabling
check boxes work the same way as those for the Repeat P0 Sweeps.
The first field to the right of the check box determines the number of times a sweep is repeated. The next
field to the right is the period of the sweep (in seconds). Finally, the text following the equal sign is the
total time of the sweep in min:sec.
Again, on the right, if the ‘Add Delay’ check box is checked, an additional delay period (equal to the
preceding normal slow repeat sweep period) between the end of the theta stimulation and the
resumption of the normal slow repeat sweep stimulation. Otherwise there will be no added delay, and it is
possible that the first normal sweep will occur immediately after the theta stimulation without any obvious
gap.
If single trains are in ‘Train’ sweeps, repetitive sweeps of trains will then produce a theta stimulation.
In normal LTP experiments, a Train T0 Sweep generates many (say 100) S0 pulse stimulations, and a
eliciting a single Train T0 Sweep would deliver an S0 train stimulation to the preparation. Similarly, a
Train T1 Sweep generates many S1 pulse stimulations, and a eliciting a single Train T1 Sweep would
deliver an S1 train stimulation to the preparation.
As described in Section 4.9.1, the stimulations in Pulse P0 and P1 Sweeps and Train T0 and T1 Sweeps
can be quite varied. For instance, a Train or Pulse Sweep can generate repetitive trains (theta burst) and
primed burst stimulation. In fact, a Pulse Sweep can generate train stimulation, and a Train Sweep can
generate single pulse stimulation.
4.4.2.4 Evoked Single and Repeat PulseSweeps cannot occur in an Average Loop
When Single and Repeat PulseSweeps are evoked during an Average Loop, they will not be run during
the Average Loop, but only after it is finished. This is shown in Fig. 4.4.2.4.1, where LTD stimulation was
evoked by cliking the ‘Repeat P0’ sweep Run Button during an Average Loop, but the actual LTD
stimulation was delayed until after 2nd Average Loop was exited.
Running Single and Repeat PulseSweeps during an Average Loop would have caused a serious error in
the calculation of averaged PulseSweep values such as Peak Amplitude because in an Averaging Loop
the P0sweeps and the P1sweeps are being averaged by adding to an array in each pulse sweep that
sums all the sweeps and then is divided by the number of loops. If Single or Repeat P0 or P1 sweeps
were also evoked, this would have added to the sum array but would not have changed the number of
loops – hence the average would have been wrong.