Speech communication in everyday life often takes place in the presence of multiple talkers or background noise. Understanding speech is difficult in such noisy environments and is even harder when the interfering noise consists of intelligible speech as compared to unintelligible sounds. Given that speech is a complex auditory signal that carries linguistic information, interference between distracting sounds and target speech can occur at multiple levels of the speech processing hierarchy: interference could occur during the auditory analysis of speech, or at a later stage during the decoding of linguistic information. Interfering signals with different types of acoustic and linguistic information should thus influence different aspects of the neural processing of target speech. To test this hypothesis, we primarily use magnetoencephalography (MEG) in this project. We examine how and to what extent competing linguistic information interferes with the neural processing of target speech. This project aims to better understand how the auditory system deals with these kinds of noisy environments and to investigate the important roles of neural oscillations for speech processing.