Verbal labels facilitate tactile perception.

One of the key statements of linguistic relativity is that language has a causal effect on perception. Although much previous research has addressed such putative language perception causality, no firm proof is available thus far which demonstrates that verbal labels help or otherwise influence perceptual processes. Here, we tested the hypothesis of language perception causality by using novel, minimally-different tactile-patterned stimuli applied to the finger, which initially could not be discriminated by our participants. By combining novel verbal pseudoword- and novel tactile-patterned stimuli in an implicit learning experiment, we show a language-induced facilitation in tactile-patterned stimulus discrimination. After one week of intensive yet implicit learning of tactile stimuli in the presence of irrelevant consistent verbal labels, participants demonstrated significant discrimination improvement. In contrast, the same participants showed no improvement in discriminating tactile-patterned stimuli that had been learnt in the context of variable linguistic stimuli. These results show that specific mental links between verbal labels and perceptual information brought about by their correlated presentation enable one to better discriminate said sensory information (and build percepts).