On 2017 Mar 08, Lydia Maniatis commented:

The authors discuss “face signals” and “face aftereffects” and “face-selective neurons,” but these terms have no conceptual backing. The underlying basis of the “aftereffects” that have been reported using faces is not known; we could argue (always prematurely) that adaptation to particular contour patterns affects the organization of these contours into faces. To give a parallel, the case of color aftereffects doesn’t license us to posit adaptation of “color-selective” neurons, even though the perception of color is a “high-level” process; we know that they are the perceptual consequences of pre-perceptual, cone-level activity.

The idea of face-selective neurons is highly problematic, as are all claims that visual neurons act as “detectors.” (They are essentially homuncular, among other problems). What, exactly, is being detected? If we draw any shape and stick two dots on it along the horizontal, it becomes a face. It cannot be overstated the extent to which references to visual neural processes in this paper are premature.

With respect to functional explanations, if we don’t know the reason for the effects – again, references to “face-selective neurons” are hopelessly vague and have serious logical problems – then it’s premature to speculate if and what.

All of this seems almost moot given the comments in the discussion that “Our results seemingly contradict those of Kiani et al. (2014), who found that identity aftereffects did decay with time (and that this decay was accelerated when another face was presented between adaptor and test).” The authors don’t know why this is, but speculate that “it is likely that the drastically different temporal parameters between the two studies contributed to the different findings… It is plausible that this extended adaptation procedure would have induced larger and more persistent aftereffects than Kiani et al.'s procedure…. It is plausible that aftereffects resulting from short-term fatigue might recover rapidly with time, whereas aftereffects resulting from more structural changes might be more long-lived and require exposure to an unbiased diet of gaze directions to reset.”

Given that the authors evidently didn’t expect their results to contradict those being discussed, these casual post hoc speculations are not informative. “Plausibility” is not a very high bar, and it is rather subjective. What is clear is that the authors don’t understand (were not able to predict and control for) how variations in their parameters affect the phenomenon of interest.

On 2017 Mar 08, Lydia Maniatis commented:

The authors discuss “face signals” and “face aftereffects” and “face-selective neurons,” but these terms have no conceptual backing. The underlying basis of the “aftereffects” that have been reported using faces is not known; we could argue (always prematurely) that adaptation to particular contour patterns affects the organization of these contours into faces. To give a parallel, the case of color aftereffects doesn’t license us to posit adaptation of “color-selective” neurons, even though the perception of color is a “high-level” process; we know that they are the perceptual consequences of pre-perceptual, cone-level activity.

The idea of face-selective neurons is highly problematic, as are all claims that visual neurons act as “detectors.” (They are essentially homuncular, among other problems). What, exactly, is being detected? If we draw any shape and stick two dots on it along the horizontal, it becomes a face. It cannot be overstated the extent to which references to visual neural processes in this paper are premature.

With respect to functional explanations, if we don’t know the reason for the effects – again, references to “face-selective neurons” are hopelessly vague and have serious logical problems – then it’s premature to speculate if and what.

All of this seems almost moot given the comments in the discussion that “Our results seemingly contradict those of Kiani et al. (2014), who found that identity aftereffects did decay with time (and that this decay was accelerated when another face was presented between adaptor and test).” The authors don’t know why this is, but speculate that “it is likely that the drastically different temporal parameters between the two studies contributed to the different findings… It is plausible that this extended adaptation procedure would have induced larger and more persistent aftereffects than Kiani et al.'s procedure…. It is plausible that aftereffects resulting from short-term fatigue might recover rapidly with time, whereas aftereffects resulting from more structural changes might be more long-lived and require exposure to an unbiased diet of gaze directions to reset.”

Given that the authors evidently didn’t expect their results to contradict those being discussed, these casual post hoc speculations are not informative. “Plausibility” is not a very high bar, and it is rather subjective. What is clear is that the authors don’t understand (were not able to predict and control for) how variations in their parameters affect the phenomenon of interest.