XOR style tasks for testing visual object processing in monkeys

Using visually complex stimuli, three monkeys learned visual exclusive-or (XOR) tasks that required detecting two way visual feature conjunctions. Monkeys with passive eXpOSUrc to the test images, or prior experience, were quicker to acquire an XOR style task. Training on each pairwise comparison of the stirnuli to be used in ail XOR task provided nearly complete transfer when stimuli became intermingled in the full XOR task. Task mastery took longer, ZICCUracy was lower, and response times were slower for conjunction stimuli. Rotating features of the XOR stimuli did not adversely effect recognition speed or accuracy. (c) 2005 Elsevier Ltd. All rights reserved.