The format of PRT files
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- Category: File Formats
- Last Updated: 17 April 2018
- Published: 17 April 2018
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PRT files are simple text files containing the informations defining a stimulation protocol. The entries should normally not be changed directly in the file due to the risk of introducing errors. You can use the "Stimulation Protocol dialog" to specify the protocol. The information below is for programmers who want to read or write PRT files.
A PRT file starts with a file version entry and a ResolutionOfTime entry (both new since BV v4.2). The ResolutionOfTime entry can be set to "Volumes" or "msec". If set to "Volumes", the protocol behaves identical to the PRT format prior to BV v4.2. If set to "msec", times of events can be specified not in multiples of TR's (i.e. volumes) but in msec resolution. This is particularly important for event-related experiments.
The next seven entries specify global settings for the appearance of a stimulation protocol within time course plots and dialogs for defining statistical questions. These general settings are followed by the actual entries defining the conditions of the protocol. The entry "NrOfConditions:" specifies how many different conditions occurred within the experimental run. For each condition, a variable-length block of informations follows defining the intervals belonging to that condition. An example PRT file with short descriptions is shown below (note that such descriptions are not allowed in real PRT files):
|
PRT FILE |
DESCRIPTION |
|
|
FileVersion: |
2 |
file version (new entry since BrainVoyager v4.2) |
|
ResolutionOfTime: |
Volumes |
Volumes or msec (new entry since BrainVoyager v4.2) |
|
Experiment: |
Objects in LVF or RVF |
name of conducted experiment |
|
BackgroundColor: |
0 0 0 |
RGB components for background color of time course plots |
|
TextColor: |
255 255 217 |
RGB components for text color, i.e. axis labels |
|
TimeCourseColor: |
255 255 255 |
RGB components for line color of time course plots |
|
TimeCourseThick: |
3 |
Line thickness of time course |
|
ReferenceFuncColor: |
255 255 51 |
RGB components for line color of reference time course plot |
|
ReferenceFuncThick: |
2 |
Line thickness of reference time course |
|
NrOfConditions: |
3 |
number of conditions within run |
|
Fixation |
name of first condition |
|
|
9 |
number of intervals belonging to first condition |
|
|
1 |
2 |
interval specifying first piece of time belonging to condition 1 |
|
11 |
18 |
second interval belonging to condition 1 |
|
: |
: |
|
|
123 |
126 |
Nineth interval belonging to condition 1 |
|
Color: |
192 192 192 |
Color for vertical segments in time course plots belonging to condition 1 |
|
Images, left |
name of second condition |
|
|
4 |
number of intervals belonging to second condition |
|
|
3 |
10 |
|
|
35 |
42 |
(*1) |
|
67 |
74 |
|
|
99 |
106 |
|
|
Color: |
255 0 0 |
Color for vertical segments in time course plots belonging to condition 2 |
|
Images, right |
name of third condition (last condition since NrOfConditions = 3) |
|
|
4 |
number of intervals belonging to third condition |
|
|
19 |
26 |
|
|
51 |
58 |
|
|
83 |
90 |
|
|
115 |
122 |
|
|
Color: |
0 210 0 |
Color for vertical segments in time course plots belonging to condition 3 |
(*1) Intervals can be in "Volumes" (multiples of TR, measurements, time points) or in "msec". If in "Volumes", the interval values are inclusive, i.e., the pair [35 42] defines an interval of 8 units (time points).The actual duration of an interval is obtained by multiplying an interval with the value of the TR. If, for example TR = 3000 ms, the duration of the mentioned interval is (42-35+1)*3000ms = 8*3000ms = 24sec. Intervals values are interpreted as msecs if the "ResolutionOfTime" entry specifies "msec".
The following figure shows the mapping between the entries in the file and corresponding values in the "Stimulation Protocol dialog":
The following figure shows the mapping between the protocol entries and the display within time course plots:
