Abstract
Titchener’s fourth law of attention—the law of prior entry—states that the object of attention comes to consciousness more quickly than the objects which we are not attending to, or otherwise that attended stimuli are perceived prior to unattended stimuli. The phenomenon of prior entry is typically investigated in a temporal order judgment task (TOJ). When visuospatial orienting is elicited volitionally, the effect of the contingency manipulation—intended to engender the shift of attention—on perceptual tasks (i.e., TOJs, colour perception) is task-dependent (Shore, Spence & Klein, 2001; Redden, d’Entremont & Klein, 2017a/b). Our recent work has shown that, regardless of the type of TOJ task used to measure prior entry, there is a robust facilitatory effect on colour perception in an orthogonal task due to volitional visuospatial orienting. However, whether the colour perception benefit is for the probability or the resolution of encoding depends on the type of TOJ task being administered. Across experiments, whether individuals are required to make TOJs to moving, or onset, or both, types of stimuli has an effect on whether prior entry is observed—when presented alone we observe prior entry for onset but not motion stimuli, but when intermixed we observe prior entry for motion but not onset stimuli. The implications for task-dependent attentional control settings on the perceptual consequences of volitional visuospatial orienting will be discussed.
Acknowledgement: NSERC and KIllam Trusts