The event-related potential (ERP) technique was used to investigate the neural dynamics in processing different levels of the hierarchical syntactic structure during comprehension of Chinese sentences with the ba construction. In these sentences, the structural auxiliaries, which mark either the adjective (-de) or the adverb (-di) category, were embedded in a hierarchical structure at the lower level, i.e., BA-adjective (-de)-noun-verb, or at the higher level, i.e., BA-noun-adverb (-di)-verb. Violations of the lower-and the higher-level structural constraints were constructed by misapplication of these structural auxiliaries. Participants were required to read all the sentences for comprehension and to complete a sentence recognition test at the end of the experiment. Violation of the lower-level constraints elicited a left-lateralized, anteriorly maximized negativity, whereas violation of the higher-level constraints elicited a right anterior negativity (RAN) and a right centro-parietal negativity (N400) from 300 to 500ms postonset of the auxiliary phrase. Neither type of violation led to a late positivity effect on the critical auxiliary phrases. These findings suggest that processing different levels of syntactic hierarchy during natural language comprehension may involve different neural mechanisms.

During communication, speakers and listeners need the mechanisms of executive control to organize thoughts and actions along internal goals. Speakers may use executive functions to select the right word over competing alternatives to refer to the concept in mind. Listeners may use executive functions to coordinate the outputs of multiple linguistic processes to reach a coherent interpretation of what others say. Bilinguals may use executive functions to control which language is in use or to switch from one language to another. The control mechanisms recruited in language processing may be similar to these recruited in perception and attention, supported by a network of frontal, parietal and sub-cortical brain structures. Here we review existing evidences regarding the involvement of domain-general executive control in language processing. We will explain how executive functions are employed to control interference in comprehension and production, within and across languages.

The issue of how phonological information becomes available in reading Chinese and the role that it plays in lexical access was investigated for Chinese compound words, using pseudohomophone effects in lexical and phonological decision as a diagnostic tool. Pseudohomophones were created by replacing one or both constituents of two-character compound words with orthographically dissimilar homophonic characters. Experiment 1 found that mixed pseudohomophones sharing one constituent with their base words were more difficult to reject than control nonwords in lexical decision. Pure pseudohomophones sharing no constituents with their base words did not show this effect. Experiment 2 used mixed pseudohomophones and found an interaction between base word frequency and the frequency of constituent characters in determining pseudohomophone effects. Experiment 3 used a phonological decision task and found exceptionally poor performance for pure pseudohomophones. These results are interpreted in an interactive framework where the direct mapping from orthography to semantics is dominant and phonology plays a subsidiary role.

Feedback-related negativity is a negative deflection in brain potentials associated with feedback indicating monetary losses or response errors. Feedback-related negativity is studied primarily in paradigms in which participants experience negative outcomes that appear to be contingent upon their previous choices. This study investigated whether feedback-related negativity can be elicited by a randomly assigned cue indicating potential monetary loss. The expected loss or win can be materialized or averted depending on participants’ performance in a subsequent game. Compared with the win cue, the loss cue elicited a weak but significant feedback-related negativity-like effect. It is suggested that the anterior cingulate cortex, which generates feedback-related negativity, may function as a pre-warning system that alerts the brain to get ready for future events. NeuroReport 17: 1649-1653 © 2006 Lippincott Williams &Wilkins.

Congenitally blind adults’ performance in spatial and nonspatial peripheral auditory attention tasks was compared with that of sighted adults in a paradigm manipulating location-based and frequency-based inhibition of return concurrently. Blind study participants responded faster in spatial attention tasks (detection/localization) and slower in the nonspatial frequency discrimination task than sighted participants. Both groups, however, showed the same patterns of interaction between location-based and frequency-based inhibition of return. These results suggest that early vision deprivation enhances the function of the posterior-dorsal auditory ‘where’ pathway but impairs the function of the anterior-ventral ‘what’ pathway during peripheral auditory attention. The altered processing speed in the blind, however, is not accompanied by alteration in attentional orienting mechanisms that may be localized to higher cortices. NeuroReport 17: 1449-1452 © 2006 LippincottWilliams &Wilkins.