Delay-interval illumination changes interfere with pigeon short-term memory

Area of Science:

• Cognitive psychology
• Animal behavior

Background:

• Delayed matching-to-sample tasks assess short-term memory.
• Environmental stimuli can influence memory performance.

Purpose of the Study:

• To investigate the effect of delay-interval illumination changes on pigeon short-term memory.
• To determine if illumination itself or changes in illumination disrupt memory.

Main Methods:

• Pigeons were trained on a successive delayed matching-to-sample task.
• Delay-interval illumination conditions were altered during test sessions compared to baseline.
• Matching performance was compared between baseline and altered illumination conditions.

Main Results:

• Altering delay-interval illumination significantly disrupted matching performance.
• Disruption occurred regardless of whether illumination increased or decreased.
• The presence or absence of illumination change during the test session did not alter the disruption.

Conclusions:

• Illumination per se during delay intervals does not impair pigeon short-term memory.
• Changes in delay-interval illumination retroactively interfere with short-term memory in pigeons.