Brief presentations are sufficient for pigeons to discriminate arrays of same and different stimuli.

Four pigeons learned to tell same from different picture arrays. Each array flashed for only two seconds. Birds pecked one key for "same" and another for "different."

Training kept going until each bird picked the right key on at least 80 out of 100 trials.

All four birds hit the 80 % mark. Average look time was just two seconds. Quick flashes were enough for the birds to choose correctly again and again.

Johnson et al. (1968) showed that earlier discrimination practice makes pigeons notice key colors faster. Williams et al. (2002) now shows that, once attention is trained, birds need only a blink to judge whole arrays.

Pisacreta (1982) kept pigeons accurate while a target moved every 0.5 s. The new study keeps accuracy with 2-s still pictures. Both prove that brief windows can hold strong stimulus control.

Henson et al. (1979) found that dense arrays speed early learning but distinctive stars help later. A et al. used mixed arrays and still got fast learning, showing that "same vs. different" cues can override layout tricks.

Your learners do not need long looks to tell items apart. Two seconds of clear "same" and "different" examples can build the skill. Use quick flash cards or brief tablet screens in matching tasks. Start with short exposures and let speed work for you.