14 What Are the Brain Mechanisms Underlying Syntactic Operations? Anna Fedor, Csaba Pléh, Jens Brauer, David Caplan, Angela D. Friederici, Balázs Gulyás, Peter Hagoort, Tatjana Nazir, and Wolf Singer Abstract This chapter summarizes the extensive discussions that took place during the Forum as well as in the subsequent months thereafter. It assesses current understanding of the neuronal mechanisms that underlie syntactic structure and processing…. It is posited that to understand the neurobiology of syntax, it might be worthwhile to shift the bal- ance from comprehension to syntactic encoding in language production The Main Questions The focal question posed to our group can be answered on many descriptive levels. At the finest-grained level are processes that store and activate syn- tactic representations in neuronal networks. Here, relevant variables are the frequency of spikes, the temporal structure of spike sequences, changes in sen- sitivity and number of synapses, and modifications of excitability. To date, however, little is known about the physiological basis for syntactic processing at this cellular level. In our discussions we therefore concentrated on relating syntactic representations and processes to larger-scale neural features, such as event-related potentials (ERPs) and areas of the brain determined anatomically or functionally. It is important to realize why issues related to the “localization”of cognitive skills in the brain, including the processing of language, are hotly debated. These issues have a long history in neuroscience, and the answers given were always dependent on the original assumptions, the methodology, and methods