Knowledge Base

Experiment in EthoVision XT

Arena-Hardware Mapping

1. In EthoVision XT, choose Setup > Arena Settings and click the Arena-Hardware Mapping button.
2. In the Arena-Hardware Mapping window, select the row for UB FCS Door. Next, click the Test button.
3. The Test UB FCS Door window opens on the screen. Open/close the door of the corresponding cubicle and check the message displayed in the window (Door Open? True or false).

Verify That the Shocker Gives a Shock

Place a LED diode between two bars of the shocker grid, or touch a bar with a phase detector.

If the shocker is connected correctly and working, the LED turns on. You can also touch the grid bars, however a current intensity around 1 mA is the threshold of feeling. A lower current may not be felt.

Measure the Amplitude of the Shock

Important: For this you need an oscilloscope and an oscilloscope probe with insulated channel and a 100 K resistor.

1. Set the oscilloscope to 50V/DIV and time base 10 ms.
2. Connect the oscilloscope probe with a 100 K resistor to the shock grid, as indicated in the following picture.
3. In EthoVision XT, in the Arena - Hardware Mapping window, select the shock device for a specific cubicle and click Test. Set the shock intensity to 1.5 mA.
4. Click the Test button to activate the shock. You should see a square wave on the display of the oscilloscope. Read the amplitude there; remember that with the current settings one vertical division corresponds to 50 V. Once you know the voltage, the current is equal to the voltage divided by the resistance (in this example 100000).

Trial Control Settings

Follow this section to learn how to program EthoVision XT to send commands to the FCS devices at the right time during data acquisition.

Basic Structure: Actions and Conditions

To activate/deactivate a stimulus, use the Actions function. In general, two actions must be separated by some time. Below is an example of activation of a stimulus for one second.

1. Choose Setup > Trial Control Settings.
2. In the Components pane, under Actions click the button next to the device name that you want to use, and specify the type of action.
3. In most cases you need to add a number of boxes in a sequence. For example, the sequence Shock On (Action) > Time Condition > Shock Off (Action) defines the activation of the shock for a specific time set in the Time Condition.
4. Click and drag from the center of one box to the next to connect the boxes with the arrows.

Depending on how you map the devices on the Arenas, this action can be carried out in one or more cubicles simultaneously.

Recurring Stimulation Using Sub-Rules

In most cases you need to administer a stimulus at regular intervals, for example every minute. Instead of repeating the sequence for each round, create a Sub-rule that contains the actions you want to repeat. Specify how often and when the routine is repeated in the Sub-rule settings.

In the following example, a Sub-rule with the same instructions will be repeated 15 times. The shock is given every minute:

• After the start of the trial, the software waits one minute (box A).
• The Sub-rule reference box (B) activates the Sub-rule (C).
• The stimulus is given as above (D-E-F).
• A time condition of 59 seconds (G) ensures that the next stimulus is given exactly one minute later (1 s of shock + 59 s = 60 s).
• The Sub-rule is repeated 15 times as specified in the settings of box B. After that, the trial stops (box H).

Cued Conditioning: Pairing Tone and Shock

The following example follows the protocol by Curzon et al. (2009) [In Buccafusco (ed). Methods of Behavior Analysis in Neuroscience, Chapter 2]. During the conditioning session:

• A tone (Frequency 1000 kHz, Amplitude 50% of the maximum) is presented for 15 seconds.
• During the last 2 seconds of the tone presentation, the shock is administered (0.5 mA).
• Tone and shock end at the same time.
• After the shock, a period of 60 seconds with no stimuli follows.

If you want to have this sequence repeated a number of times, place it within a Sub-rule. In this example the Sub-rule is called by a Reference rule after 120 seconds of habituation.

Controlling Lights

• IR Light: The FCS provided by Noldus has the IR light activated by default. If the IR light is off, activate it at the start of the trial by adding an action for the IR light just after the Start Trial box.
• Visible Light: In many FC protocols a house light illuminates the test chamber continuously during testing. Add an action for the UB FCS Visible Light and insert the Light On Action box after the Start Trial box. Add a second action box (with a Light Off action) immediately before the Stop Track box.

Controlling the Fan

The fan is by default activated when you start the cubicle. To ensure that the fan is on at the start of a trial, in Trial Control Settings click the button next to UB FCS Fan and insert the Fan On Action box after the Start Trial box.

Notes:

• If you add a Fan On Action at the start of the trial, the fan switches on at the start of the trial and switches off at the end of the trial.
• If you do not add any action about the fan in the Trial Control Settings:
  • If the fan was already on at the start of the trial (for example after you start up the cubicle), the fan stays on during the trial.
  • If the fan was off, for example when testing it in the Trial Control Settings, it stays off during the trial.

Analyze Data Using Trial Control Events

If you want to analyze the data in specific time segments, you can use the actions and conditions of Trial Control Settings to define specific intervals.

For More Information

For more information and examples of actions, conditions and sub-rules, see the EthoVision XT 18 - Trial and Hardware Control - Reference Manual. To open this manual, choose Apps > Noldus > EthoVision XT 18 Other Documentation.

Detection Settings

Release the subjects in the FCS cages, then choose Setup > Detection Settings to detect the subject.

Source: EthoVision XT 18 - Application Manual, Noldus Information Technology