Compound words consist of two or more words which combine to form a single word or phrase that acts as one. In English, the head of compound words is usually, but not always, the right-most root (e.g., “paycheck” is a noun because the head, “check,” is a noun). The current study explores the effects of head position on language control by examining language switching performance through electroencephalography (EEG). Twenty-one pairs of Chinese (L1)–English (L2) bilinguals performed cued language switching in a simultaneous production and comprehension task. The results showed that bilinguals recognized the head position earlier both in production and comprehension. However, the language control of the head position during production occurred in the middle stage (N2), but in the late stage (LPC) during comprehension. These findings indicate that the head position in compound words exerts differential influences on language control.

Theories of lexical processing differ as to how multimorphemic words, such as compounds, are mentally processed. The most recent findings seem to support the dual route hypothesis, which assumes that complex words can be stored and retrieved either whole or by decomposition into their constituents. Despite great efforts to investigate the cognitive mechanisms involved in processing complex words, very little is known about how compounds are represented in the brain. The present study was designed to address this issue in a group of 20 left-hemispheric stroke patients who were submitted to four picture-naming tasks involving nouns, verbs, noun-noun (NN) and verb-noun (VN) compounds. To determine the brain lesions implicated in these tasks, we analyzed patients’ performances together with their lesions using Voxel-based Lesion Symptom Mapping (VLSM). Results showed that while NN involved the same temporal areas as nouns, VN (although they belong to the noun category) involved different fronto-temporal regions. This latter finding is discussed within the view that distinct mechanisms process the different constituents of complex words. (JINS, 2010, 16, 433–442.)