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ARTICLESProbabilistic word pre-activation during language
comprehension inferred from electrical brain activity.com/natureneurosciencehttp://www.nature2005 Nature Publishing Group Katherine A DeLong1, Thomas P Urbach1 & Marta Kutas1,2Despite the numerous examples of anticipatory cognitive processes at micro and macro levels in many animal species, the idea
that anticipation of specific words plays an integral role in real-time language processing has been contentious. Here we exploited
a phonological regularity of English indefinite articles (an precedes nouns beginning with vowel sounds, whereas a precedes
nouns beginning with consonant sounds) in combination with event-related brain potential recordings from the human scalp to
show that readers brains can pre-activate individual words in a graded fashion to a degree that can be estimated from the
probability that each word is given as a continuation for a sentence fragment offline. These findings are evidence that readersuse the words in a sentence (as cues to their world knowledge) to estimate relative likelihoods for upcoming words.Despite the variety of real-time processing domains across the phylogenetic spectrum in which anticipatory processing has been observed (at
both micro and macro levels), the concept of anticipation has played a
relatively minor role in language processing theories. Human languages
offer unlimited possibilities not only for saying new things but also for
saying old things in new waysfar too many ways, some have argued,
to make prediction of words a viable and effective strategy except when
contextual constraint is unusually high1. Accordingly, early language
processing models often included some form of memory buffer wherein
sentential elements were temporarily stored for later integration at
phrasal, clausal or sentence boundaries26.Sincethe1970s,however,the
consensus view has been that sentence processing is continuous and
incremental, with provisional commitments made that at least temporarily resolve linguistic ambiguities as each word is processed upon its
occurrence and rapidly integrated into the sentence representation716.More recently, a few researchers have argued for the predictive power
of context in generating expectancies during sentence processing, but it
has proven difficult to distinguish prediction from integration. What
some researchers take as evidence for neural pre-activation (prediction,
at a psychological level), others take as a sign of the ease or difficulty in
integrating words into message-level representations upon, but not
before, their occurrence. A case in point is the N400 component
observed in event-related brain potential (ERP)...