Components of visual prior entry

Abstract

The prior entry hypothesis contends that attention accelerates sensory processing, shortening the time to perception. Typical observations supporting the hypothesis may be explained equally well by response biases, changes in decision criteria, or sensory facilitation. In a series of experiments conducted to discriminate among the potential mechanisms, observers judged the simultaneity or temporal order of two stimuli, to one of which attention was oriented by exogenous, endogenous, gaze-directed, or multiple exogenous cues. The results suggest that prior entry effects are primarily caused by sensory facilitation and attentional modifications of the decision mechanism, with only a small part possibly due to an attention-dependent sensory acceleration.

Shifts of criteria or neural timing? The assumptions underlying timing perception studies

“…Unfortunately, participants in psychophysical experiments seem rather prone to shifting their criteria based on incidental features of the question being asked (e.g Bedell, Chung, Ogmen & Patel, 2003;Clifford, Arnold & Pearson, 2003), and it has proven rather difficult to completely eliminate these biases . This is one reason that some investigators have suggested, albeit tentatively, that simultaneity judgements might make a better choice of task than temporal order judgements when the PSS is an important parameter for investigation (Schneider & Bavelier, 2003;van Eijk, Kohlrausch, Juola & van de Par, 2008;Zampini, Shore & Spence, 2005).…”

“…To elucidate the often unstated assumptions underlying analyses of simultaneity data, we can take as a starting point the derivation provided by Schneider and Bavelier (2003). This derivation builds on work by Sternberg and Knoll (1973), Allan (1975) and Ulrich (1987).…”

“…For example, in the more straightforward of their derivations, Schneider and Bavelier (2003) adopted the triggered-moment model (Venables, 1960). This model suggests that the first stimulus to arrive centrally triggers a time-consuming mental process, and that judgements of simultaneity occur when the second stimulus arrives while this process is being conducted.…”

Relative timing: from behaviour to neurons

“…Schneider & Bavalier [30] proposed a number of possibilities for how attention could affect TOJ: (i) through sensory interaction between cue and stimulus (exogenous attention), (ii) by reducing the transmission time of the attended stimulus (attending to a feature or spatial location) and (iii) by affecting the decision mechanism. Regarding (i), exogenous (visual) attention cues are by definition presented near the item to be attended; thus, sensory interactions are inevitable.…”

Crossmodal processing

“…Should any behavioural facilitation of participants' performance in response to the visual target seen in such studies be accounted for in terms of an exogenous shift of spatial attention towards the location of the auditory cue, or to the multisensory integration of the cue and target stimulus into a single multisensory stimulus (cf. Schneider and Bavelier 2003)? At present, we simply do not know.…”