Using Photobeams To Measure Anxiety-Like Behavior In Mice

There is a wide range of instruments and mazes available to scientists who use animal models to gain a deeper understanding of behavior and how it works. Many of these instruments include mazes, recording devices and sensors to help scientists monitor animal behaviourisms, and using photobeams is one such example. This article will focus on how photobeams are used to measure anxiety-like behaviors in mice and why it is advantageous to the tests.

What are Photobeams? 

Photobeams are detectors or sensors that project a beam of light that, when crossed, sends a notification to the central system it is connected to. The sensors are made with a transmitter and a receiver, and a light beam is projected by the LED and focused into a single stream of light. When the light hits an object or is interfered with by something, the receiver will obtain it and process it. 

How are Photobeams Used to Measure Anxiety-Like Behavior? 

There are many different situations that can be set up in an open-field testing environment to monitor anxiety-like behavior in rodents. Whether scientists choose to use an elevated plus-maze, the light-dark exploration or the social interaction test, photobeams can be used to record a rodent’s movements. 

In an open-field exploration test, mice or rat testing subjects are monitored as they explore a new environment. Stress is induced due to the isolation the subjects face, as they are separated from other rodents they are usually caged with and because the field is lit with a bright light. Where do photobeams come into play? Photobeams are used to create a grid within the open field testing area and each time the subject crosses one of the lines, it is recorded against a point-scoring system.

San Diego Instruments for Behavioral Monitoring

San Diego Instruments have designed and manufactured a Photobeam Activity System (PAS) Open-Field that is the ideal solution for monitoring rodent behavioral patterns. The system utilizes photobeam technology to accurately and reliably identify movements and record the data you need for analysis. 

The PAS comes with software suitable for open field tests and its advanced technology allows for the monitoring and data acquisition of the following:

  • beam interruptions
  • ambulation movements
  • central peripheral movements
  • fine movements 
  • movement positions (x and y)
  • time stamps

 These options provide scientists with highly accurate data, reducing the risk of human error or the need to rely on memory as the data will all be stored in a single file. Key features of the PAS device include the option to configure up to 32 testing stations, which is ideal for larger testing groups, play back the subject’s movements and set up automated sessions. Additional benefits of the PAS Open-Field include the following:

  • Auto-replay is available for reviewing the results 
  • Error-free analysis with color-coded cables, connections and frames
  • Define your study by inputting the parameters and subject identifiers
  • Visual display of the animal’s movements

Contact us today for more information on how our PAS Open Field can be used to support your rodent behavior monitoring needs.