Biol. [mod.L. f. Gr. θίγμα touch + τάξις arrangement, disposition.] The way in which an organism moves or disposes itself in response to a touch stimulus, i.e., by being attracted (positive thigmotaxis) or repelled (negative thigmotaxis).
1900. B. D. Jackson, Gloss. Bot. Terms, 270/2. Thigmotaxis … is a synonym [of Thigmotropism].
1905. Nature, 31 Aug., 426/2. The ‘Thigmotaxis’ exhibited by an oxytrocha moving round a spherical egg, unable to leave its surface.
1909. J. W. Jenkinson, Experim. Embryol., 272. Thus we have positive and negative heliotropism, galvanotaxis, geotropism, galvanotropism, thigmotaxis, and so on.
So Thigmotactic a. [Gr. τακτικ-ός pertaining to arrangement], of, pertaining to, or exhibiting thigmotaxis; hence Thigmotactically adv.
1900. in Amer. Jrnl. Psychol., XII. 141. One is the thigmotactic reaction. Starting with the moving infusorian, we find that it reacts to contact with solid bodies of a certain physical texture by suspending part of the usual ciliary motion. Ibid. (1901), 229. A definite rat-hole consciousness that acts, as it were, thigmotactically.
1903. Science, 8 May, 738. The ventral surface of planarians is strongly positively thigmotactic, whereas the dorsal surface is negatively thigmotactic.
