written test or oral test,
how long does it take them?
how accurate are they?
(the following day)
how much long-term memory they have?
diagnostic color enhances performance across a broad range of tasks, including subordinate-level object recognition, object/scene-naming speed and accuracy, visual search, and face recognition.
This enhancement relies on the prototypical color of the object or scene being stored in a mental representation, so that it can be called upon for a match to the incoming stimulus.
Hering called this mental representation the memory color of a familiar object and postulated that it was automatically established through frequent experience of actual instances of the object.
Hering also proposed that memory color affects immediate perception; the attributes of the stimulus that elicits it are varied.
natural objects are characterized by multiple visual attributes – by color, texture, shape, and motion; and by surface attributes such as translucency and gloss.
Yet memory color is typically studied using uniformly colored stimuli with a few recent exception that employ photographs of natural familiar objects, which found that achromatic settings for 2D images of familiar objects deviated more from neural in the presence of luminance shading or combined luminance-shading and surface markings, relative to uniform surfaces.
None of these latter works examine polychromaticity per se, instead confound intrinsic and extrinsic factors in the stimulus representation, particularly with respect to luminance variations, making it difficult to establish the contribution of intrinsic polychromaticity to the findings.
Monochromatic (a) and polychromatic (b) light
Monochromatic is the term used for light consisting of waves of onewavelength only. One speaks of a pure spectral color, which is comparable with a sinusoidal tone in acoustics. Light from the sun or from artifical light sources (except for lasers) is polychromatic: it contains waves of different wavelengths.
Polychromatic is the term used for light consisting of two or more wavelengths. Light from the sun or from artifical light sources (except for lasers) is polychromatic. The spectral distribution (spectrum) indicates the relative intensity of the different wavelengths present. The wavelength range is referred to in terms of bandwidth: wide band light appears whitish, narrow band light colored. Polychromatic light can be compared with a sound containing many tones.
The intrinsic surface polychromaticity of natural objects may also contribute to an inherent.
Shape is another cue to object identity that has been frequently investigated, but its contribution to memory color is still debated.
Therefore, a second goal of this work is to examine the effect of the 2d contour of natural objects using a different finer-resolution method to measure memory color.
Duncker first emphasized the importance of shape in eliciting memory color by demonstrating that a desaturated leaf shape appeared greener than a donkey shape, even both shapes were cut from the same green paper and lit by the same reddish illumination.
other studies have concluded the opposite, that memory color effects are strongest when stimulus information is limited. More explicitly, there is no effect of stimulus shape on memory color.
Olkkonen et al. suggest that the influence of 2D contour cues alone may be minimal: when observers were asked to adjust the color of a 2d uniform stimulus to appear neutral, no significant difference was found between stimulus shapes – natural object contours vs. disks.
Mean memory colors measured with a yes-no paradigm, do not differ for uniformly colored 2D disks and 2D natural object contours.
The contribution of 3D shape to memory color, specifically in the context of natural objects, is still largely unknown.
To simplify the study, we limited the measurement of memory color to one dimension, the hue.
the memory color associated with a familiar object is not a single color, but a range of colors.