Measurement notes
Define center-zone size as a fixed coordinate region or percentage of arena area. Report center entries and total distance because immobile animals can show low center time without a specific avoidance phenotype.
Endpoint methods library
Open-field zone occupancy endpoint
Center time
Duration or percentage of an open-field session spent in a predefined center zone.
Unit
seconds or percent session time
Readout
Time inside the predefined center zone of an open-field arena
Assays
Open field, novelty-induced exploration, anxiety-like behavior screens
Decision summary
Use center time when the study needs an open-field avoidance or exploration readout. Interpret it alongside total distance, speed, entries, wall time, lighting, arena size, and habituation because center occupancy is highly activity-dependent.
| Primary value | Time inside the predefined center zone of an open-field arena |
|---|---|
| Common units | Seconds, percent session time, center entries, latency to center |
| Compatible assays | Open field, novelty-induced exploration, anxiety-like behavior screens |
| Required boundary | Center-zone geometry, body-point rule, session window, and lighting |
| Do not infer alone | Anxiety, exploration, risk-taking, sedation, or motor function without controls |
Interpretation limit
Lower center time can support thigmotaxis or avoidance, but low locomotion, arena novelty, lighting, odor, wall-following strategy, tracking loss, and sedation can produce the same endpoint shift.
Data capture
Store animal ID, arena dimensions, center-zone coordinates, body point, session duration, center time, periphery time, center entries, latency to center, total distance, speed, lighting, and exclusions.
Confound checks
- Center zone size or body-point rule differs between analyses.
- Low locomotion, freezing, sedation, or sickness reduces center entries.
- Lighting, odor, wall texture, floor material, or arena cleaning changes exploration.
- Start position or habituation differs across animals.
- Tracking reflections, bedding, shadows, or poor contrast alter zone assignment.
Reporting checklist
- Arena dimensions, center-zone geometry, body-point rule, and coordinate calibration.
- Lighting, session duration, start position, habituation, and cleaning protocol.
- Center time, periphery time, center entries, latency to center, distance, and speed.
- Tracking method, frame rate, valid-frame threshold, and smoothing settings.
- Handling of rearing, grooming, freezing, wall climbing, and missing frames.
- Companion endpoints such as open-arm time, distance traveled, freezing, or grooming.
References
Evidence notes
Endpoint pages should cite the method literature behind the scored value and keep high-specificity protocol claims qualified unless the source supports them.
Related workflow paths
Endpoint articles link to adjacent products, software workflows, and sibling endpoints where the connection is useful and already routable.
