# Choose a variable to view real-time

By default, the dependent variables Velocity (with the statistic Mean) and Movement (with the statistic Cumulative duration, and only for the Moving state) are already displayed. You can specify any dependent variable, except behaviors recognized automatically.

To choose a variable

1.In the Analysis Results and Scoring pane, click the Dependent Variables tab.

2.Click the Show/Hide button on the toolbar, and select Show Dependent Variable.

3.Select the variable you want to monitor during the trial. Make sure that you specify the correct body point and statistic.

note You cannot select a Free interval variable to view during acquisition.

Below you find four examples.

To remove a variable

On the Dependent Variables tab of the Analysis Results and Scoring pane, right-click anywhere in the variable column and select Delete.

Open field: view the Movement variable

In this example, the aim is to calibrate the Movement variable in order to detect bouts of locomotor activity. Movement is based on the subject’s speed.

1.Follow the procedure above to choose Movement. Click its properties button. On the Trial Statistics tab, choose Current.

2.During the trial, watch the subject and monitor the current value of Movement in the Dependent Variables tab. Note when the behavior of the subject and Movement do not match.

▪If the subject is walking and the cell under Moving-Current says false, you must reduce the Start velocity and Stop velocity thresholds.

▪Conversely, if the subject is still and the cell Moving-Current says true, you must increase those thresholds. Note that only displacement in space of the animal should be scored as Moving, not other movements like grooming or body axis curling.

▪If there are many rapid transitions false-true-false but the animal seems not to change its behavior, then you can increase the difference between Start velocity and Stop velocity, or increase the Averaging interval, for example from 1 to 3.

3.Click the properties button for Movement and adjust the settings accordingly.

4.Check again the match between behavior and the values in the Movement cell. If necessary repeat steps 3-4 until you have a good agreement between the two.

See also Movement in the Analysis profile.

Porsolt swim test: view the Mobility state variable

In this example, the aim is to calibrate the Mobility state variable in order to quantify swimming behavior. Mobility state has three possible states and is based on the temporal change in the subject’s detected area.

1.Add Mobility and Mobility state. For both variables select Current as a Trial Statistic, and leave the other settings as they are.

2.During the trial, watch the subject and monitor the current values of Mobility and Mobility state in the Dependent Variables tab. Note when the behavior of the subject and Mobility state do not match.

First, focus on the mobility thresholds, then on the averaging interval.

For example, to calibrate the Immobile state, watch the subject and check the value of Immobile-Current. If the subject swims (or struggles) and Immobile-Current is true, take note of the running values of Mobility. This tells you how much the animal’s area changes with time. You must set the Immobile below threshold smaller than those values.

The Immobile-Current value is true (second column), and the rat in the video is swimming. Mobility (first column) shows that the change in the area is around 5%. For correct scoring of the Immobile state, the Immobile below threshold of Mobility state should be set below 5%.

3.Click the properties button for Mobility state and change the threshold accordingly.

4.Watch the subject again and monitor the value of Immobile-Current. If the subjects moves and Immobile-Current says true, the threshold must be lowered further.

▪At some point the animal still floats, something you would like to score as Immobile. Check that Immobile-Current is true. If not, the corresponding threshold must be increased slightly.

▪If there are rapid transitions between Immobile, Mobile, Strongly Mobile, that cannot be accounted for in the video, you can increase the difference between the two thresholds, and/or increase the Averaging interval.

5.Repeat the steps above to adjust the Highly mobile above threshold. The aim is to obtain Highly mobile-Current equal to true only when the animal struggles.

6.Visualize the trial (Plot Integrated Data) to view the events of Mobility state together with the video. You can always refine your thresholds in the Analysis profile to re-calculate the three states.

See also Mobility state in the Analysis profile.

Fear conditioning: view Activity state

In this example, the aim is to calibrate the Activity state variable in order to quantify activity levels and freezing. Activity state has four possible states and is based on the change in the pixels in the whole arena.

1.Select Activity analysis in the Experiment Settings and define the Activity settings in the Detection Settings.

2.Add Activity and Activity state to the Dependent Variables tab of the Analysis Results and Scoring pane.

3.Choose the number of states (minimum two and maximum four).

4.Leave the threshold values as they are, and set the minimum duration of a state. For example, if you think that inactivity should last at least 0.2 s, then enter 0.2.

Select Current as a Trial Statistic for both variables.

5.During the trial, watch the subject and monitor the current values of Activity state in the Dependent Variables tab. Note when the behavior of the subject and Activity state do not match.

When the animal shows the behavior that should be scored as Inactive, monitor the running values of Activity. This tells you how much the video image area changes with time. If the value of Inactive-Current is false, you must reduce the Inactive below threshold smaller than those values.

In the example above, the mouse in the video is still, but the Inactive-Current value is false (second column). Activity (first column) shows that the change in the pixels is around 0.5%. For correct scoring of the Inactive state, the Inactive below threshold should be set below 0.5%

6.Click the properties button for Activity state and change the threshold accordingly.

With the new threshold, if episodes of inactivity are not detected, then adjust the threshold in the other direction.

7.If you have more than two states, repeat the steps above to adjust the other thresholds. The aim is, for example, to obtain the value of Highly mobile-Current equal to true only when the animal struggles.

See also Activity state in the Analysis profile.

Conditioning test: view a Trial Control State variable

In this example the aim is to test whether a pellet is dropped when the animal enters the trigger zone. This is also useful to check that the zone is defined correctly.

1.Define the Trial Control rule with a Zone transition Condition to define the transition to the trigger zone and an Action to let the pellet dispenser drop a pellet. See the figure below for an example.

2.Open the Acquisition screen.

3.Choose Show/Hide > Show Dependent Variable > Trial Control State.

4.Define the Trial Control State as shown in the figure below. Select Frequency in the Trial Statistics tab.

5.Start the trial and open the Dependent variables tab of the Analysis Results and Scoring pane to view the Trial Control State. If the animal moves to the trigger zone and a pellet is dropped the Frequency increases with 1.

For simple Trial Control events, like the animal entering a zone, define a Trial Control Event instead of a Trial Control State.