Knowledge Base

Options

If you used Noldus MPEG Recorder 1.1/2.0, or MediaRecorder, and analog cameras:

• When you used MediaRecorder with a Picolo H.264 encoder board, choose Noldus Recorder and select Euresys PICOLO U4 H.264. Make sure you select the TV standard of the camera (NTSC or PAL).
• When you used an older encoder board (Picolo Diligent or IVC-4300), choose Noldus Recorder and select one of the other options.

If you used MediaRecorder, and digital cameras:

• In most cases you do not need to correct the aspect ratio. However, if you are sure the video image is distorted, select Custom and enter the correct aspect ratio.

If you used video files recorded with EthoVision XT, but in a different experiment:

• Select Noldus Recorder and select Euresys Picolo U4 H.264.

If you used video files recorded with programs other than MediaRecorder:

• Select Custom and enter the adjusted aspect ratio. See Calculate the Correct Aspect Ratio in a Video Image.

Arena - Hardware Mapping

If your experiment is set to use Trial Control hardware, the Hardware Mapping section at the bottom of the Arena Settings pane is available. Click the Arena-hardware mapping button to assign hardware devices to each of your arenas.

If your experiment consists of only one arena, the hardware is automatically assigned to this arena, so you do not have to take further actions.

If you have more than one arena, assign the hardware to the arenas manually.

See Also

• The section Assign Devices to Arenas in the EthoVision XT 19 - Trial and Hardware Control - Reference Manual. To open this manual, on the Apps screen choose Noldus > EthoVision XT 19 Other Documentation.

Trial Control Settings

Main Topics And Tasks

• Introduction to Trial Control
• The Start-Stop Trial Rule
• Examples of Start-Stop Trial Rules
• Programming Trial Control
• Further Information on Trial Control

Important: This chapter describes the Trial Control functions of the EthoVision XT Base version only. For a detailed overview of conditions, creating sub-rules and controlling hardware devices via the USB-IO box, see the EthoVision XT 19 - Trial and Hardware Control - Reference Manual. To access this manual, on the Apps screen choose Noldus > EthoVision XT 19 Other Documentation.

Introduction To Trial Control

Learn About

• Why Use Trial Control?
• Important Terms in Trial Control

Why Use Trial Control?

Start And Stop Data Acquisition

Trial Control allows you to automate your experiment. Let EthoVision XT control the start and stop of data acquisition (tracking) depending on time, the behavior of the subjects and other conditions. For example:

• Start tracking when the subject is released and detected in the open field.
• Start tracking at exactly 12:30:00, and stop tracking after one hour.
• Stop tracking when the rat has reached the platform in the Morris water maze, or one minute after the start in any case.
• Stop tracking after the animal has been in the closed arms of the Elevated Plus Maze for five minutes.
• Stop tracking when the subject has explored an object for five minutes.

See Also

• The Start-Stop Trial Rule

Advanced Trial Control

With the EthoVision XT Trial and Hardware Control Module, you can also:

• Define conditioning routines for the subject, based on sequences of conditions and actions that are repeated a number of times (sub-rules).
• Control hardware devices, like a pellet feeder, or the arms of a radial maze. Your EthoVision XT license must include the Trial and Hardware Control module.

For more information about advanced trial control options, see the EthoVision XT 19 - Trial and Hardware Control - Reference Manual.

Important Terms In Trial Control

Trial Vs. Track

A Trial is a single, uninterrupted acquisition session. The trial can be viewed as a container for the data collected in one recording session. It starts when you give the Start command in acquisition and stops when the tracks for all arenas and subjects have stopped.

A Track is the actual recording of a subject's position and behavior. The start of a track may or may not coincide with the start of the trial. This depends on your Trial Control Settings. If you use the default Trial Control Settings, the track starts 1 second after the animal has been detected in the arena and stops when you stop the trial.

Conditions And Actions

A Condition is a statement that EthoVision evaluates. A condition can be based on time, presence of the subject in a zone, any variable that quantifies behavior, or the state of a device connected to EthoVision XT.

An Action is a command executed on a variable or a hardware device. You can therefore control your experiment by linking conditions with actions.

Example: In a Morris water maze test, stop tracking when the rat is detected on the platform (provided that the platform has been defined as a zone). The action is Stop tracking and the condition is Rat detected on the platform. A condition is followed by an action. The condition checks that the animal is in the zone named "Platform". The action "Stop track" is taken when the condition is met.

The Start-Stop Trial Rule

Learn About

• The Default Start-Stop Trial Rule

What Do You Want To Do?

• Control the Start of Tracking
• Control the End of Tracking
• Split a Multi-Day Test in Multiple Trials