Acquire a series of trials - live

Aim

To carry out video tracking in a live situation, for a number of times (trials), in a predefined list. Video is not recorded.

Trials and inter-trial intervals

In the following example, the duration of the trials is assumed to be constant (for example, 5-minutes trials in an open field). Click the Start series button to start acquisition. The inter-trial interval is not applied before the start of the first trial. You specify the inter-trial interval in the Acquisition Settings window.

If you want to start the next trial before that end of the inter-trial interval, click the Skip countdown button.

 

important The serial acquisition is interrupted automatically when the available disk space gets lower than 100 MB. EthoVision XT checks the available disk space before starting a new trial. Close the experiment, clean up some disk space, and then resume acquisition.

Prerequisites

1.See also Before you start acquisition.

2.In the Experiment Settings, under Video Source select Live tracking.

3.Make sure that the Trial list includes all trials that you plan to acquire. If necessary, open the Trial List and add trials. Select a combination of Arena Settings, Trial Control Settings and Detection Settings for each planned trial.

4.Choose Acquisition > Open Acquisition. In the Acquisition Settings window, select Track all planned trials and specify the Inter-trial interval (H:mm:ss).

 

The name of the first planned trial in the Trial List appears in the field next to Trial.

Procedure

1.Choose Acquisition > Start Trial, or press Ctrl+F5, or click the Start series button in the Playback Control window.

 

2.Release the animal for the first trial in the arena.

3.The trial is stopped automatically according to the rules set in the Trial Control Settings. Remove the animal from the arena, clean the experiment setup and prepare the next animal.

The video window shows the countdown (inter-trial interval).

 

4.At the end of the countdown, the next trial starts. Release the animal in the arena.

5.To stop the series of trials:

The series stops automatically when the last planned trial has been tracked.

You can stop the series manually at any time. Choose Acquisition > Stop Trial, or press Ctrl+F6, or click the Stop series button in the Playback Control window.

 

If you stop batch acquisition manually, all trials acquired up to that time are saved, including the current one that was interrupted. Click the Start series button again to complete the series. If necessary, redo the trial that was interrupted. See Redo a trial

Notes

▪If cleaning the experiment setup takes less time than the Inter-trial interval, and you do not want to wait until the end of the countdown, skip the remaining time and start the next trial. Click the Skip interval and Start trial button (or press Ctrl+F5).

 

▪During the inter-trial interval, you can view information on when the next trial starts. In the Acquisition Settings window, next to Track all planned trials you see [name of next trial] starts in [H:mm:ss].

In the Video window you see [name of next trial] (Number of trials remaining) Starts in [H:mm:ss] (the last, in red). This text is always shown, even when you specify to hide the overlay text.

▪Automatic analysis does not start if you stop the series manually.

▪If you save video while tracking, saving the video at the end of each trial takes time. The Inter-trial interval countdown only starts after the video has been saved. For this reason, the total time between the end of the i-th trial and the start of the i+1-th trial may be longer than the inter-trial interval.