An objective technique for recording shock-induced aggression in unrestrained pairs of rats.

The team built a metal pole that sits between two rats. When the rats fight after foot-shock, they bump the pole. Each bump flips a counter.

They ran 30-minute sessions. Shock strength went from 0.5 mA to 4.0 mA. Two observers also watched and scored fights by hand.

The goal: see if pole hits match real fights and if higher shock makes more fights.

Pole hits and hand counts lined up almost perfectly. More shock equaled more hits. At 4 mA the counter logged about 60 fights per session.

The device worked even when no person was in the room. It gave an honest, round-the-clock tally of shock-induced aggression.

Dardano (1970) showed that pigeons peck angrily when food stops or the ratio gets big. W et al. now give us a cheap way to count that sort of emotion-driven burst in rats.

Mosk et al. (1984) found that once shock is strong enough to keep avoidance going, turning it higher only wrecks the rat’s timing. W et al. show the same rule for fighting: above 2 mA the hit curve flattens, so stronger shock adds little new aggression.

FARMELong (1963) invented a lever box that scores complex rat sequences to test drugs. W et al. copy that spirit but swap the lever for a pole, turning animal-made motions into clean numbers without a human timer.

If you study problem behavior in animals, this gadget gives you honest data while you sleep. No video coding. No missed bites. Swap the pole for a touch-sensitive pad and you can track client-induced aggression in a shelter cage or classroom corner. Next time you test a treatment, let the environment count for you.