Heringn.

1891 M. Foster Text Bk. Physiol. (ed. 5) IV. iii. iii. 1232 Hering's theory attempts to reconcile..the various facts of colour vision with the supposition that we possess..six fundamental sensations.

1902 Encycl. Brit. XXI. 749/2 Hering's theory proceeds on the assumption of chemical changes in the retina under the influence of light.

1902 Encycl. Brit. XXI. 749/2 Hering's theory accounts satisfactorily for the formation of coloured after-images.

1911 G. M. Gould Pocket Med. Dict. (ed. 6) 415 Hering's Law. The distinctness or purity of any sensation or conception depends upon the proportion existing between their intensity and the sum total of the intensities of all simultaneous sensations and conceptions.

1934 H. C. Warren Dict. Psychol. 123/2 Hering after-image, the first positive after-image, or after-sensation, which occurs following a brief light-stimulus.

1934 H. C. Warren Dict. Psychol. 123/2 Hering illusion, an illusion, or distorted perception of visual form, observed when a number of lines radiating from a point are crossed by two parallel lines on opposite sides of the point and equidistant from it; the parallel lines appear to bow outward, i.e. away from the central point.

1934 H. C. Warren Dict. Psychol. 123/2 Hering theory of vision, the theory..according to which visual sensations are due to three pairs of antagonistic processes in the optic system.

1971 Jrnl. Gen. Psychol. 84 164 The Zöllner and Hering illusions are examples of phenomena in which the overall pattern dominates the geometry and leads to the perceptual distortion of straight lines into curved lines.