Accurate freezing detection for fear conditioning
2D-AI improves freezing detection versus limited legacy tools, providing freezing time and freezing ratio as advanced endpoints for conditioning studies.
FCFear5 min read
Fear Conditioning
Fear Conditioning: Principles & Protocol
Overview
Contextual & Cued Fear Conditioning, rooted in Pavlovian learning, assesses formation, consolidation, extinction, and anxiety-like fear responses. Neutral context or tone is paired with footshock; later re-exposure without shock elicits freezing, indexing fear memory strength.
It is a core model for amygdala–hippocampus–prefrontal fear circuits, PTSD-related research, extinction therapies, cognitive evaluation, and related drug development.
Methods
- 1Pair conditioned stimuli (tone/light) with aversive footshock to assess fear learning and memory.
- 2Typical sequence: training day (habituation, baseline freezing, tone–shock pairing, context stay); context test at 24 h (same chamber, no shock, score freezing); cued test at 48 h (altered context, 3 min baseline then 3 min tone, score freezing). Freezing is the primary fear readout.
Software capabilities
Analysis parameters
| Parameter | Description | Unit |
|---|---|---|
| sample_name | Sample name | — |
| group_label | Group label | — |
| total_distance | Total distance | cm |
| average_speed | Average speed | cm/s |
| xxx_distance | Distance in a region | cm |
| xxx_distance_ratio | Region distance ratio | % |
| xxx_average_speed | Average speed in a region | cm/s |
| xxx_time | Time in a region | s |
| xxx_time_ratio | Region time ratio | % |
| xxx_number_of_entries | Entries into a region | count |
| outside_distance | Distance outside regions | cm |
| outside_distance_ratio | Outside distance ratio | % |
| outside_time | Time outside regions | s |
| outside_time_ratio | Outside time ratio | % |
Advanced parameters
| Parameter | Description | Meaning | Unit |
|---|---|---|---|
| freezing_time | Freezing time | Defensive immobility with a rigid posture when threatened or strongly stimulated | s |
| freezing_ratio | Freezing time ratio | Freezing time / total time | % |