The effects and interactions of top-down influences on word recognition

It is widely acknowledged that top-down influences such as our prior experiences, knowledge, and expectations influence the way in which we perceive information. However, little is known how different sources of top-down influences interact when modifying sensory information. This study combined behavioural and EEG measures to investigate the effects and interactions of two expectation sources - informative hints (semantic priming) and stimulus repetition - in an auditory task requiring the recognition of spoken words embedded in noise. We manipulated participants' (N = 23) prior knowledge of the target stimuli by presenting valid, invalid, or no hints (presented acoustically or visually) and then assessed how their performance differed over multiple repetition blocks. Initial differences across hint types emerged but diminished over repetitions. In contrast, repetition-based learning showed stronger and more sustained effects, overriding both hint type and modality. While the interactive effects between hints and repetitions were also observed, they were less consistent across hint types and modalities. These findings suggest that informative cues and repetition rely on distinct learning mechanisms that jointly shape speech perception.