For example, the observers adjusted the color of a banana, whose canonical color was yellow, to a slightly bluish hue in order for it to appear gray. This phenomenon suggests that the observers perceived fruit and vegetable images as slightly colored in their canonical color even when the target object was achromatic. This bias in perception was compensated for by their setting the fruit and vegetable colors slightly opposite to their canonical colors. Hansen et al. named these shifts of subjective gray point the memory color effect and proposed that perception of an object’s color was not determined by incoming sensory data alone, but was modulated by the prior experience of having seen the natural color of the object.