Language processing is grounded in brain function. Words of different semantic categories are processed in different cortical areas. Several examples of this distributed processing are given: colour words are processed in visual areas, whereas action words are processed in motor areas. The processing of action words in described in more details. A pathological condition, Parkinson’s disease, is used as an illustration of a motor impairment that selectively affects the comprehension of action words. This comprehension impairment is attributed to a difficulty in accessing the procedural knowledge carried by this specific class of words.