Behavioral & physiological endpoint methods.

Force at which a paw withdrawal response occurs during von Frey or electronic aesthesiometer testing.

Percent time or duration spent immobile except for respiration during fear, threat, or defensive-behavior assays.

Total path length covered during a defined assay window, commonly used as an activity, exploration, or motor-confound readout.

Duration or percentage of a trial spent inside a predefined arena, arm, chamber, target quadrant, platform, or stimulus zone.

Time from trial start to reaching a hidden platform, escape box, shelter, goal arm, or other task-defined escape criterion.

Time an animal remains on a rotating rod, beam, ladder, or elevated motor task before meeting a fall or failure criterion.

Time from placement on a heated plate to a predefined nocifensive response such as hindpaw licking, withdrawal, shaking, or jumping.

Time from radiant heat or tail-immersion stimulus onset to tail withdrawal, flick, or removal according to a predefined cutoff rule.

Time from radiant heat application under the hind paw to paw withdrawal during plantar thermal testing.

Peak or integrated movement response to a startling acoustic pulse, usually measured with a force plate, accelerometer, or startle chamber.

Percentage of total fluid intake consumed from a sucrose solution during a two-bottle or equivalent preference test.

Percent reduction in startle response when a weak prepulse precedes a stronger startling pulse.

Time an animal remains on an accelerating or fixed-speed rotating rod before falling, passive rotation, or task-defined failure.

Number or rate of paw slips while an animal traverses a narrow beam or balance beam under a defined scoring rule.

Time to orient downward and descend a vertical pole during a task used to assess movement initiation and coordination.

Change in time spent in a cue-paired compartment after conditioning with a rewarding or aversive stimulus.

Duration spent floating with only movements needed to keep the head above water during a forced swim test.

Duration spent immobile while a mouse is suspended by the tail during a defined scoring window.

Relative exploration of a novel object compared with a familiar object during a recognition-memory test.

Volume of oxygen consumed per unit time, measured by open-flow respirometry, as a primary index of aerobic metabolic rate at rest or during exercise.

Volume of carbon dioxide produced per unit time, measured by open-flow respirometry, used with VO₂ to derive substrate use and energy expenditure.

Ratio of CO₂ produced to O₂ consumed (VCO₂/VO₂), used to estimate the balance of fat versus carbohydrate oxidation.

Whole-animal energy use per unit time, derived from VO₂ and VCO₂, reported per animal and normalized to body or lean mass.

Clock time at which sustained daily activity begins, used as the phase marker for entrainment and phase-shift studies.

Length of one endogenous circadian cycle measured in constant darkness, the core readout of intrinsic clock speed.

Strength of the day-night difference in activity, quantified as relative amplitude (RA) between the most and least active hours.

Proportion of total activity occurring in the dark versus light phase, a simple index of how well behavior is partitioned by the clock.

Degree to which rest and activity break into many short bouts within a day, quantified as intradaily variability (IV).

How reproducible the 24-hour activity pattern is from one day to the next, quantified as interdaily stability (IS).

Strength of the 24-hour component in the activity spectrum, an objective measure of rhythm robustness from periodogram or cosinor analysis.

Daily timing and distribution of food and water intake, including meal timing, frequency, and the dark/light intake ratio.