Task for natural image repetition paradigm and responses to four example stimuli in monkey H
(A) Structure of a single trial. Monkeys performed a change-detection task. After a variable duration, a small, local Gaussian contrast decrement appeared at an unpredictable location on the object (indicated on third panel at end of arrow; the size depended on the animal; see STAR Methods).
(B) Structure of the trial sequence within and across sessions. Within a session, stimuli could repeat immediately or with up to four intervening stimuli. A given stimulus (e.g., the yellow pepper in this example) could occur in different parts of the session on different days, and with different intervening stimuli.
(C) Responses to four example stimuli (inset in last column) in monkey H. First column: dMUA response. Second column: LFP power change spectra (stimulation/baseline). Third column: MUA-LFP PPC spectra (gray line: average baseline activity). Shaded areas indicate ±1 SEM across 10 sessions. Stimulus presentation always lasted from 0 to at least 1.5 s, and spectral analyses used data from 0.5 to 1.5 s.