Gina R Kuperberg, MD PhD
Biography
Monday morning, June 10th
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Predicting Meaning: What the Brain tells us about the Architecture of Language Comprehension
It is well established that we draw upon our real-world knowledge to predict upcoming
events and even individual words. I will discuss evidence that the neurocognitive
mechanisms that we engage in retrieving conceptual information associated with incoming
words are quite distinct from those engaged when these predictions are disconfirmed
by the input. Drawing broad links with computational models conceptualizing language
comprehension as an incremental process of belief updating, I will suggest that
the engagement of these distinct neurocognitive systems allows for comprehension
that is both highly efficient and highly flexible (1).
I will first discuss studies using event-related potentials (ERPs) to examine online
brain activity during sentence and discourse comprehension. I will then draw some
(still tentative) links between this ERP literature and some relevant fMRI and MEG
studies. Finally, I will discuss the advantages of a predictive comprehension system.
Predicting correctly clearly offers advantages in terms of computational efficiency.
Here I will argue that the costs incurred when we predict incorrectly are also crucial
for successful and flexible comprehension. Neurocognitive responses triggered by
prediction errors may rescue us from interpretation errors in noisy environments,
may allow us learn novel events, and may enable us to flexibly adjust our comprehension
strategies in response to everchanging task and environmental demands.
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Kathleen McKeown, PhD
Biography
Wednesday morning, June 12th
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Natural Language Applications from Fact to Fiction
Much research in the natural language field has been carried out on news, given
the large amount of annotated data now available for this genre.
Certainly, the ability to analyze the facts of real world events, enabling systems
to answer questions and summarize the events of the day is an important application.
As research has moved to analysis of new genres, whether fact, opinion or fiction,
new approaches to existing applications have arisen and opportunities for new applications
have emerged. In this talk, I will present research in my group at Columbia as it
has moved from news to scientific articles to online discussion forums to novels.
I will touch on summarization, open-ended question answering, social influence and
social networks.
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