High-resolution control of selective attention
In all species, the capacity of sensory processing is heavily constrained by bioenergetic limitations. Covert attention, the ability to selectively enhance perceptual functions without reorienting sensory organs, is an essential component of perceptual systems and fundamental to most human activities. Current models of attention assume that covert shifts of attention reallocate these resources to selected locations in the visual periphery, and that neural and cognitive resources uniformly monitor the high-acuity region at the center of gaze, the foveola, with no need for selective processing at this smaller scale.
A spatial cueing task in the parafovea (A) and in the foveola (B)
My research has shown that attentional control continually occurs, at a microscopic level, where the observer already looks, i.e. within the central 1 degree region of the visual field. Covert attention selectively improves and speeds-up both detection and discrimination at loci only a fraction of a degree apart at the center of gaze (Poletti et al, 2017, Nature Neuroscience). The outcome of this research indicates that the neuronal processes responsible for controlling attention must include dedicated high-resolution representations of the central region of the visual field, which are commonly believed not to be part of neuronal saliency maps. Current research in the lab further examines attention control at the scale of the foveola by looking at the factors driving high-resolution saliency maps of the foveal input and at the attentional effects associated with eye movement planning at the foveal scale.