TABLE 2.

Derived variables calculated from 19-day behavioral sensitization data.

Behavioral variable	Description (derived variable)
Day 1 locomotion	Distance traveled on 1st exposure to open field and saline injection (Day 1)
Day 2 locomotion	Distance traveled on 2nd exposure to open field and saline injection (Day 2)
Habituation	Change in locomotor activity from Day 1 to 2 (Day 2–1)
Initial locomotor response	Locomotor response after 1st exposure to cocaine (Day 3–2)
Initial locomotor sensitization	Distance traveled after 2nd cocaine exposure (Day 5–3)
Locomotor sensitization	Area under the curve (AUC) of distance across 5 consecutive cocaine exposures (Day 3,5,7,9,11)
Sensitization expression	Locomotor response to cocaine after 1-week withdrawal (Day 19–11)
Conditioned activation	Locomotor response to saline after repeated cocaine exposures (Day 12–2)