ETT Olfactometer 2, Manual

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© Emerging Tech Trans, LLC
was predefined. Currently, it starts out with a 5 s delay. Then the odor connected to channel 1 will be
applied to the subject for 5 s. To now synchronize the onset of this group with the occurrence of the TR,
a trigger condition named ‘MRI TTL sync’ or whichever name is preferred can be inserted. The duration
of 5 s in this is arbitrarily chosen for readability. Anything that is now vertically aligned in the group
settings view of this group, will be delayed until the trigger condition is fulfilled (in this case a TTL pulse
is received on the TRIGGER IN port of the ETT Olfactometer). The checkboxes
Delay onset until and
blocking both must be check in this case. Other possible trigger conditions can be chosen from a list in
the drop-down menu. To only mark the current section of the paradigm for example as a stimulus
period or certain condition like in Figure 74, the two checkboxes should be unchecked and the trigger
condition
none must be checked. Currently there is no further indication within the paradigm as to
which trigger condition is currently selected. Clicking on a specific segment marked by a blue box
surrounded with a red dotted rectangle will reveal the specific setup and can be changed at any time.
Figure 73 - Using the Add / edit Triggers / Labels / EEG DINs tab to synchronize each group onset with an external TTL pulse. If
this interface is not used with our EEG interface system, any label is allowable (even non-numerical). The timing of such labels
will be tracked in output protocol files and might be used during data analysis later.
Figure 74 – To simply label a section (in this case as stimulus presentation), uncheck the delay checkbox, select none as the
trigger type and uncheck the blocking checkbox.
Case 2 – specific exhalation onset condition
It might further be useful under certain conditions to tie an Exhalation onset to a specific time point in
the paradigm so the stimulus odor will already be delivered during the onset of the subjects next
inhalation. In this case, the group
’s device actions are already defined:
- delay time with all valves closed of 5 seconds