Retrospective attention reveals a decaying theta rhythm in conscious access to a preceding stimulus

Conscious perception is often presumed to arise immediately upon external stimulation. However, retroperception—conscious access to a stimulus after it has disappeared—challenges this perspective by demonstrating temporally flexible awareness. The fine-grained temporal dynamics governing retroperception, however, remain unknown. Here, we tested three competing models for the temporal architecture of retroperception: a monotonic decay, a sustained oscillation, and a damped oscillation. We implemented a retro-cue paradigm and densely sampled behavioral reports. Through spectral analysis and computational modeling, we found that both behavioral accuracy and subjective visibility exhibited theta-band fluctuations, with model comparison modestly favoring a damped oscillatory profile over sustained oscillatory or non-oscillatory alternatives. Furthermore, we found that oscillations in accuracy and visibility were temporally aligned, suggesting temporal coordination between attention and perception during post-stimulus access. These findings suggest that conscious access to recent sensory information may be rhythmically structured and temporally limited, placing computational constraints on models of retroperception.