ABSTRACT
Language is defined as a brain-based system allowing for interpersonal communication using sounds, symbols, and words to express a meaning, idea, or abstract thought. Human beings’ ability to understand and produce language involves a considerable amount of brain resources. For over a century, our understanding of brain mechanisms for language came mainly from lesion studies; essentially, lesion studies pointed to the existence of some association between a damaged brain region and a given set of language deficits (e.g., Broca, 1865; Wernicke, 1874). In recent decades, imaging methods—which permit one to measure various indirect indices of ongoing neural activities arising from the brain “in action”—have revolutionized cognitive neuropsychology and neurolinguistics, providing a new way of mapping language abilities and, in particular, much better evidence about both the anatomical and temporal aspects of brain processes. Currently, a fundamental question in cognitive neuroscience concerns where and how the normal brain constructs meaning, and how this process takes place in real time (Kutas & Federmeier, 2000). Imaging methods have been highly successful in investigating semantic information processing, revealing cortical area networks that are certainly plausible, given our previous knowledge of cerebral anatomy and lesion studies. Several imaging methods allow one to explore different aspects of the brain: spatial distribution (using hemodynamic methods), temporal deployment (using electrophysiological methods) or both (using emerging imaging methods). This chapter focuses on the convergent contribution of different imaging methods to our understanding of the neural bases of the semantic processing of words. First, an overview of imaging methods will be presented. Then, the converging results concerning the neurobiological bases of semantic processes will be reported for each method mentioned above. Since the number of publications on language processing and, more specifically, on the neurobiological bases of the semantic processing of words exceeds what can be reviewed here, this chapter focuses on the most representative papers in each area.
