Attentional attractors and visual awareness

The relationship between attention and awareness is hotly debated. In particular, a current controversy revolves around whether attention is a condition (either necessary or sufficient) for conscious experience. In this presentation I will argue that the debate itself is misguided, and rooted in an erroneous conception of the way attention functions. Spatial attention is often likened to a spotlight, but this metaphor is inadequate: It cannot account for the reduced sensitivity at unattended locations that accompanies perceptual facilitation at attended locations, nor for the flexibility of attention, which can be divided over several peripheral locations. Here, I will describe recent psychophysical work that systematically explored the effects of both the validity and number of peripheral cues. A series of experiments demonstrated that dividing attention impairs sensitivity at the cued locations, but improves it at uncued locations. These findings are consistent with a model in which attentional cues act as attractors for spatially-tuned receptive channels: Cueing alters channels’ spatial tuning, increasing their density near a cue and decreasing it elsewhere. Multiple cues pull in different directions, reducing both of these effects. Attentional attractors thus account for these and various other findings, and offer a viable mechanism for attention’s effects. Importantly, if attention is simply a change in the spatial tuning of retinotopic channels, then the baseline state is not inattention but rather an unbiased distribution of channels. Changing the distribution of channels in retinotopic space thus constitutes attention – and in the absence of a biologically plausible scenario in which all channels are withdrawn from a specific location, there is no point in talking about a condition in which attention is absent. Instead, I will use the results of a different recent study demonstrating the independence of attention and emotion in access to awareness to propose that efforts should be focused on defining the causal clusters that lead to conscious perceptual experience.