Multichannel Systems LTP-Director Manual - Manual (Page 38)

LTP-Director Manual
34
Pulse Interval
The pulse interval lasts between 0.5 and 180 seconds. This interval refers to one stimulation
pathway. If you are using two stimulation pathways, pathway S2 will be delivered time delayed
after pathway S1. The time delay between a stimulus on pathway S1 and S2 will be half of the
selected pulse interval. Example: Selected a pulse interval of 1 min and two pathways. There will
be one stimulus every 30 s alternately on pathway one and two.
Selecting the Stimulation Electrodes
You can select stimulation electrodes for one or two independent stimulation pathways
(S1 and S2). Please use the white electrode field in the blue Control Window Test Mode.
The LTP-Director can deliver two independent stimulation pathways to different electrodes.
Up to four electrodes can be selected for each pathway. The electrodes of stimulation pathway
S1 are labeled with small red squares in the upper left corner of the electrode symbol in the
electrode grid. Electrodes belonging to stimulation pathway S2 are labeled in black. Selected
pulse parameters apply to both pathways. All selected electrodes per pathway are active at
the same time.
To select an electrode for stimulation pathway S1, just click on the electrode you want to select,
it will be marked in red. To select an electrode for S2, hold the Shift key and click on the
electrode, it will be marked in black. To deselect an electrode, click on the electrode symbol again
or press Shift key and click again. LTP-Director does not allow to select more than four electrodes
for one pathway.
In the data display the data traces belonging to one pathway are labeled in the corresponding
color, in red (S1) or black (S2).
The signals of these two stimulation pathways S1 and S2 are delivered alternately. The pulse
interval refers to one pathway. So, if the pulse interval is 60 s, for example, there will be a
stimulus pulse from all stimulating electrodes of pathway S1, after 30 s a stimulus pulse from all
stimulating electrodes of pathway S2. After another 30 s again stimulus pulse from S1 and so on.
Important: It is possible to change the stimulation electrodes while the data acquisition is running!
In "Test Mode" both stimulation pathways are set with the same stimulation pulse parameters.
Later on in "Test pulse" tab in "Preparation" of "Measurement Mode" it is possible to set up
the amplitude of the stimulation pathways independent of each other.