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Attention can be directed to particular spatial locations, or to objects that appear at anticipated points in time. While most work has focused on spatial or temporal attention in isolation, we investigated covert tracking of smoothly moving objects, which requires continuous coordination of both. We tested two propositions about the neural and cognitive basis of this operation: first that covert tracking is a right hemisphere function, and second that pre-motor components of the oculomotor system are responsible for driving covert spatial attention during tracking. We simultaneously recorded event related potentials (ERPs) and eye position while participants covertly tracked dots that moved leftward or rightward at 12 or 20°/s. ERPs were sensitive to the direction of target motion. Topographic development in the leftward motion was a mirror image of the rightward motion, suggesting that both hemispheres contribute equally to covert tracking. Small shifts in eye position were also lateralized according to the direction of target motion, implying covert activation of the oculomotor system. The data addresses two outstanding questions about the nature of visuospatial tracking. First, covert tracking is reliant upon a symmetrical frontoparietal attentional system, rather than being right lateralized. Second, this same system controls both pursuit eye movements and covert tracking. [ABSTRACT FROM AUTHOR]

In the antisaccade task, healthy participants often make errors by saccading towards the sudden onset target, despite instructions to saccade to the mirror image location. One interesting and relatively unexplored feature of antisaccade performance is that participants are typically unaware of a large proportion of the errors they make. Across two experiments, we explored the extent to which error awareness is altered by manipulations known to affect antisaccade error rate. In experiment 1, participants performed the antisaccade task under standard instructions, instructions to respond as quickly as possible or instructions to delay responding. Delay instructions significantly reduced antisaccade error rate compared to the other instructions, but this reduction was driven by a decrease only in the number of errors that participants were aware of-the number of errors of which participants were unaware remained constant across instruction condition. In experiment 2, participants performed antisaccades alone, or concurrently with two different distractor tasks-spatial tapping and random number generation task. Both the dual task conditions increased the number of errors of which participants were aware, but again, unaware error rates remained unchanged. These results are discussed in the light of recent models of antisaccade performance and the role of conscious awareness in error correction. [ABSTRACT FROM AUTHOR]

The article reports on the visual image reflected by the painting "Las Meninas" with emphasis on the issue whether or not the mirror image was a reflection of the king and queen in the painting or by the depiction on the canvass. According to the author, there has been plenty of arguments coming from scholars regarding the issue of the reflected image. Moreover, the author argues that the issue was settled using the precepts of the laws of optics. One of the contention for applying the laws of optics is the fact that the vanishing point of the painting is to the viewer's right of the mirror.