In order to gain knowledge about the interaction between top-down expectations of listeners concerning prosodic prominence and its acoustic correlates, two exploratory empirical studies were carried out. First, native and non-native subjects rated prominences of speech read at normal and very fast - prosodically very different - speech. Later, these ratings were compared with introspective prominence ratings of different listeners. First results indicate a major influence of the introspection on prominence ratings, especially if acoustic cues are difficult to interpret, as it is the case in very fast speech. Compared to native subjects, non-natives rely less on their introspection and more on the acoustics.