Self Head-Restraining Platform
Automated behavioral testing systems enabling real-time measurements of neural activity with unprecedented precision.
An automated platform with voluntary head fixation
Enables high-throughput operant behavior under voluntary head fixation.
The ability to record neural activity during mouse behavior provides an opportunity to understand brain function at a new level of detail. Head-fixed behavioral assays in mice are perfect for this purpose because they allow real-time monitoring of neural circuits during complex operant behavior. However, traditionally mouse head fixation has proven to be extremely laborious and time-consuming. The self head-restraining platform automates the entire mouse head fixation process. By attaching to the home cage, mice have extended access to the platform to learn voluntary head fixation under lower stress conditions. This also greatly reduces experimenter time and labor, thus streamlining data collection. Once mice learn head fixation, you are ready to perform in vivo neurophysiology during operant mouse behavior!
- Mice learn voluntary head fixation in as little as two weeks, saving you time to focus on your science.
- This system is fully automated, removing unwanted experimenter bias and reducing experimenter labor.
- Train anywhere from 4 – 48 mice per day for high-throughput data collection, allowing you to generate high quality data fast!
- Includes a weigh scale for automated weight-monitoring.
- Speeds up the training process for in vivo neurophysiology during operant mouse behavior.
What is unique about the Self Head-Restraining Platform?
Head fixation during voluntary behavior in mice, rats and primates has revolutionized modern Neuroscience by making it possible to examine neural activity in real-time as animals perform operant behavior. One issue that remains however is that training laboratory animals, most commonly mice, to perform tasks while under head fixation is extremely time-consuming and labor-intensive. This greatly limits the throughput of data collection. The Self Head-Restraining Platform solves this issue by automating the entire learning process in mice:
- Attaches to the home cage creating a low-stress environment and allowing mice to learn on their own time.
- Mice have access to the platform between 4-6 hours per day, providing extended opportunity for them to self-latch.
- After self head fixation, the latching unit automatically releases the mice after 20 min allowing them to return for the home cage.
How it Works: Steps to Voluntary Head Fixation
with the Self Head-Restraining Platform
The sequence of steps leading to head fixation. The head plate (black bar on mouse’s head) is progressively restrained into rails that get narrower as the mouse moves forward(1,2). The forward motion of the head plate mechanically lifts the latching pins, which are then lowered back down due to gravity (3,4). Continued forward movement by the mouse then lifts and lowers the second set of pins (4). After the session ends, a computer controlled motor lifts up both pins and releases the mouse ( adapted from Ohara & Co., LTD & Benucci et al., 2018).
How it Works: How long does it take for mice to learn to head fix themselves?
Training mice to be comfortable performing operant behavior under head-fixation is extremely labor-intensive and can take up to several months. With the Self Head-Restraining Platform, mice are given access to the self-latching system 4-6 hours a day in 20-30 minute intervals, and learn self-latching in as little as 2 weeks. Habituation plays a key role in this process.
- Habituation: 1-2 weeks
- Self-latching for water reward: 1 week
What is habituation?
During Habituation, mice are given access to a clear PVC tube in the home cage with narrowing rails to attach the head plate as the mouse enters. The PVC tube is connected to a water supply unit so the animals are rewarded for entering the tube. The main difference with the habituation tube is that the rails do not contain locking pins, so the mouse can exit at any time.
Components: Habituation Tube + water supply setup for home cage.
How it works: Self Head-Restraining Platform main setup and design.
The self-restraint platform consists of the following main components:
- T-shaped assembly of transparent PVC pipes connecting two mouse cages to a latching unit.
- Motorized doors that give mice access to the tubes but prevent mice from entering other cages.
- IR sensors that allow precise monitoring of mouse’s position.
- A scale in the middle of the central tube for automated weight measurements.
- A servo-controlled latching system designed to minimize the mouse’s stress due to head fixation.
- Two sets of metal pins on top of the training rails at the end of the central tube that hold the mouse in place.
- A water spout with a latching sensor that initiates the software to to start the training session.
- A servo motor actuator that lifts both sets of pins after the training session allowing the mouse to return to the homecage.
Mice learn complex tasks under head fixation
Benucci and colleagues demonstrated mice learning a two-alternative forced choice visual discrimination task relying on binocular vision. Mice had to indicate whether the orientation was clockwise or counter clockwise by rotating a wheel with their front paws (2017).
In vivo physiology combined with complex task tearing under head fixation
Benucci and colleagues demonstrated that two-photon laser scanning microscopy could be performed during voluntary head fixation to monitor calcium responses of individual cells as mice learned a visual discrimination task (2017).
Moving neuroscience into the fast lane
“A new high-throughput system with an industrial approach can standardize experiments to facilitate reproducibility and data sharing.
At the RIKEN Brain Science Institute in Japan, a two-year project from Andrea Benucci’s research group and O’Hara and Co LTD. has culminated in the construction and deployment of a high-throughput system to study mouse behavior and physiology. The system aims to deliver larger, standardized datasets, a reduction in the number of experimental animals, and time-savings through complete automation.”
Read the full post from Science Daily here: https://www.sciencedaily.com/releases/2017/10/171030084736.htm