Simultaneous Monitoring of Wireless Electrophysiology and Memory Behavioral Test as a Tool to Study Hippocampal Neurogenesis

Simultaneous behavioral video tracking assessment and wireless electrons of holography recording and their integration are highly attractive and provide an interesting solution for researchers in many fields of neuroscience. The versatility of the simultaneous behavioral video tracking assessment and wireless EEG recording is one of the most significant advantages since it could be used in many experimental conditions. Demonstrating the procedure will be Florencia Mata a graduate student, and Alejandro Tapia-de-Jesus, a researcher from my laboratory.

To set up the electrophysiology device, connect the device modem to a personal computer host and turn on the modem. Turn off any other network device on the computer and silence any other wireless communication within the registration room as possible. Attach the amplifier to the back of the rat to be tested and plug in the battery to turn on the EEG device.

Two seconds after connecting, a red LED on the EEG amplifier will blink on the device indicating that the communication with the modem is active followed by the activation of a green LED light. If the communication is successful, the LEDs on the modem will begin to flash continuously. When the device communication has been successfully set up, launch the EEG software and set up the software according to the manufacturer's instructions to integrate the software with the wireless EEG acquisition device.

Then click Start Display. The EEG software will display the actual signal acquisition. To set up the behavioral tracking software, log into the account and select New Empty Experiment, and New.

Set a name for the protocol and select Video Tracking Mode. Under apparatus, set the scale moving ruler line to a position along the known length of the arena, and enter the length of the arena in millimeters in the settings panel. Under Tracking And Behavior select Zones.

In the Add Item, select New Zone and the arena length and set a name for the new zone. After setting the arena area and name the area as just demonstrated, open Animal Color and select animals are lighter than the apparatus background. Under Tracking The Animal's Head And Tail, select yes, I want the animal's head and tail to be tracked.

Navigate to Testing and Stages and select Add Item and New Stage. Name the stage acquisition. Then define the duration of the stage and repeat the setup for the short and long-term memory tests.

When all of the tests have been set up, open Procedures and define the events to be tracked for each stage. For an acquisition session in the tracking software, select Tests and Add A Test and assign a number for the animal to be tested, select Record and name the animals and session. Before placing the animal in the arena, click Play.

A waiting to start message will be displayed. Then place an animal on the arena facing a wall opposite to the objects. Click Play again and allow the animal to explore freely for 10 minutes.

Two hours after the end of the acquisition session, replace one of the objects with another object of a completely different shape, color, and texture and set up a short-term memory test in the tracking software as demonstrated. Then place the animal in the arena facing one of the walls opposite to the object as demonstrated. Press Play again and allow the animal to explore freely for 10 minutes.

24 hours after the acquisition session, set the software to record a long-term memory test and replace the object with another object completely different from that used in the short-term memory test. Then place the animal in the arena and record the animal's behavior with the software as demonstrated. Open field testing of rats that either underwent surgery while wearing the equipment or that remained intact without wearing the hardware showed no significant differences in their travel distance over the 10 minute exploration period.

Using the tracking analysis, the head time in object preference ratio can be calculated using the animal's head time spent in the object zone. A preference ratio for the time spent moving toward the objects indicating the total amount of time spent on every animal moving toward each object zone and the spent time per visit to each object can also be calculated. In this representative acquisition trial, there were no distinctions between objects in the three assessed parameters, nor were there differences in the short-term memory trial.

In the long-term memory trial however, a significantly higher exploration preference ratio for the novel object was observed as well as preference for the novel object in the time spent per visit. In this data from a single representative animal, the alpha power trended toward a decrease in short-term memory compared to acquisition and long-term memory, suggesting a desynchronization related to exploration or memory retrieval. When attempting this procedure, ensure that all EEG channels display a reliable signal to noise ratio.

It's necessary to build or use proper electrodes and motor system. This technique can help researchers answer question related to behavioral performance and electrical brain activity as evoke potential like P300 test, a Stroop or a steady state.