Previous studies have shown that language can modulate visual perception, by biasing and/
or enhancing perceptual performance. However, it is still debated where in the brain visual and
linguistic information are integrated, and whether the effects of language on perception are
automatic and persist even in the absence of awareness of the linguistic material. Here, we aimed
to explore the automaticity of language-perception interactions and the neural loci of these
interactions in an fMRI study. Participants engaged in a visual motion discrimination task (upward
or downward moving dots). Before each trial, a word prime was briefly presented that implied
upward or downward motion (e.g., “rise”, “fall”). These word primes strongly influenced behavior:
congruent motion words sped up reaction times and improved performance relative to incongruent
motion words. Neural congruency effects were only observed in the left middle temporal gyrus,
showing higher activity for congruent compared to incongruent conditions. This suggests that higherlevel
conceptual areas rather than sensory areas are the locus of language-perception interactions.
When motion words were rendered unaware by means of masking, they still affected visual motion
perception, suggesting that language-perception interactions may rely on automatic feed-forward
integration of perceptual and semantic material in language areas of the brain.