Biomedical subjects

Gregory Francis

Publications and source records attributed to Gregory Francis.

4 recordsLinked to original sources

PubMed2003

Developing a new quantitative account of backward masking.

A new general explanation for u-shaped backward masking is analyzed and found to predict shifts in the interstimulus interval (ISI) that produces strongest masking. This predicted shift is then compared to six sets of masking data. The resulting comparisons force the general explanation to make certain assumptions to account for the data. In this way, the experimental data promote the development of a new theory of backward masking. The new theory suggests interpretations of the data that are sometimes novel, often more precise, and sometimes contrary to interpretations that are prevalent in the literature.

Attention↗

PubMed2003

Interactions of afterimages for orientation and color: experimental data and model simulations.

Sequential viewing of two orthogonally related patterns produces an afterimage of the first pattern. We report an experiment that quantifies some properties of this type of afterimage. It is shown that it is important for the two patterns to have orthogonal orientations and that the appearance of the afterimage does not depend on the spatial frequency of the second pattern. We then show that Grossberg's model of interacting boundary and feature contour systems can account for the observed properties of these afterimages.

Color Perception↗

PubMed2003

MFDTool: a software program for designing optimal multifunction displays.

This paper describes a software program called MFDTool. MFDTool is used to design multifunction displays (MFDs), which enable people to interact with computer information systems. MFDTool characterizes the problem of MFD design as the identification of how people interact with the system and what types of constraints should be imposed by the designer to shape the properties of the MFD. Once this information is provided, MFDTool uses an optimization procedure to build a variety of candidate MFD designs and to identify the MFD design that best satisfies the constraints. An example of MFD design is discussed.

Algorithms↗

PubMed2002

Comment on "Competition for consciousness among visual events: the psychophysics of reentrant visual processes" (Di Lollo, Enns, & Rensink, 2000).

V. Di Lolo, J. T. Enns, and R. A. Rensink (2000) reported properties of masking that they claimed were inconsistent with all current models. The current authors show, through computer simulation, that many current models can account for V. Di Lollo et al.'s (2000) data. Although V. Di Lollo et al. (2000) argued that their data could be accounted for only with models that incorporate reentrant processing, the current authors show that reentrant processing is not necessary.

Attention↗