Open field

The open field is a generally accepted and straight-forward test to investigate anxiety-related and exploratory behavior of rodents. The open field is an empty test arena, usually round or square, in which the animal’s activity is measured. The amount of time spent close to the wall (an anxiety-like response referred to as thigmotaxis) versus the amount of time spent in, and frequencies of visits to, the inner zone are measured. Additionally, general locomotor behavior (total distance moved) is often taken into account.

Get started quickly

EthoVision XT offers a new user guided set-up; a wizard helps you get started by simply choosing your animal, your test, and some other basic settings. It leads you to a template, that you can fine-tune to your specific experiment. This way your experiment will be up and running quickly! EthoVision XT includes a variety of templates, including those for open field testing. 

Behaviors related to areas of interest 

EthoVision XT allows you to specify different zones or points of interest from the video images of your test arena. This allows the program to automatically measure parameters related to these zones. Examples include the latency to the first entrance into the inner zone of an open field. You can investigate thigmotaxis by calculating the percentage of time spent along the walls of the open field.

Automatic detection of behaviors 

In addition to center-point tracking, EthoVision XT is able to detect and track the nose point and tail base of mice and rats. This allows for the accurate measurement of animal position and it allows EthoVision XT to automatically detect behaviors such as body elongation – characteristic of the stretch-attend posture that is often considered a response to an environment that incites both fear/anxiousness and curiosity.  

Freezing behavior

Immobility is indicative of freezing behavior. EthoVision XT can detect immobility, or more specifically: you can use it to differentiate between behaviors immobile, mobile, and highly mobile. The thresholds are user-definable, so you can optimize them for your study. One way of fine-tuning these settings to fit your definition of the behavior is by performing a pilot experiment and visualizing the results alongside the video. 

There is also another way to detect freezing or immobility: the new activity detection method in EthoVision XT detects changes in the arena from one video frame to the next, in addition to tracking body points of your animal. 

Data integration 

Some studies combine behavioral data with physiology. They use telemetry to gather data such as heart and respiration rate, providing additional information on the fear response of the animal. EthoVision XT enables the integration of external data streams alongside tracking data. 

Translate data into meaningful results

Data interpretation is, of course, a crucial step in your research. EthoVision XT provides you with the useful parameters and data selection tools to perform this step, including the time spent in each quadrant, or in inner and outer zones of the arena, percentage of activity, path shape, etc. It also reveals how these numbers change over consecutive trials, or how these compare between different treatment groups. It helps you translate data into meaningful results.

Blog

Read more about research using the open field test on our blog