On 2017 Mar 20, Lydia Maniatis commented:

Commonly observable facts falsifying the conclusions of this report were available before it was published.

The conclusions to which I'm referring are the following: "First, we show that observers tend to take heavily into account the brighter parts of objects when they are asked to match the color or lightness of these objects. Second, we show that observers tend to fixate on the brighter parts of the objects as they make their match."

Of course, the samples used in the study are consistent with the claims. They consist of figures which produce percepts of partly shaded objects. In these conditions, the lighter part within the boundary of the perceived form is perceived as being "in plain view."

But there are other possible samples, specifically cases in which the lightest parts are perceived as highlights, or glare. This is the case, for example, for surfaces perceived as glossy. Here, the lightest parts are not perceived as "in plain view."

Another example from the literature is the cube demo by Purves, Shimpi and Lotto (1999). Here, the color of the upper part of the cube appears darker than its lightest region, which appears overlit.

The fact that observers, in the cases studied, tended to "fixate on the brighter parts of the objects as they made their match" does not in itself corroborate the authors' conclusion. I would predict that in the case of figures with perceived highlights, rather than perceived shadows, fixations would tend to be more on the darker - i.e. the perceived plain view - regions. This is an obvious control that should have been included in the original study. (I'm not aware that such an experiment has been performed, but maybe I'm not caught up.)

In other words, I'm claiming the direction of causality is the reverse of what is being proposed - first the percept is formed and lightness/illumination inferred, and then eye movements are organized in light of this prior organization.

The demonstration in this report that forcing fixations on particular regions affects perceived lightness doesn't undermine the above arguments.

On 2017 Mar 20, Lydia Maniatis commented:

Commonly observable facts falsifying the conclusions of this report were available before it was published.

The conclusions to which I'm referring are the following: "First, we show that observers tend to take heavily into account the brighter parts of objects when they are asked to match the color or lightness of these objects. Second, we show that observers tend to fixate on the brighter parts of the objects as they make their match."

Of course, the samples used in the study are consistent with the claims. They consist of figures which produce percepts of partly shaded objects. In these conditions, the lighter part within the boundary of the perceived form is perceived as being "in plain view."

But there are other possible samples, specifically cases in which the lightest parts are perceived as highlights, or glare. This is the case, for example, for surfaces perceived as glossy. Here, the lightest parts are not perceived as "in plain view."

Another example from the literature is the cube demo by Purves, Shimpi and Lotto (1999). Here, the color of the upper part of the cube appears darker than its lightest region, which appears overlit.

The fact that observers, in the cases studied, tended to "fixate on the brighter parts of the objects as they made their match" does not in itself corroborate the authors' conclusion. I would predict that in the case of figures with perceived highlights, rather than perceived shadows, fixations would tend to be more on the darker - i.e. the perceived plain view - regions. This is an obvious control that should have been included in the original study. (I'm not aware that such an experiment has been performed, but maybe I'm not caught up.)

In other words, I'm claiming the direction of causality is the reverse of what is being proposed - first the percept is formed and lightness/illumination inferred, and then eye movements are organized in light of this prior organization.

The demonstration in this report that forcing fixations on particular regions affects perceived lightness doesn't undermine the above arguments.