On-going Projects

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Word Comprehension

        The primary goal of the research in this area include study of language comprehension from a cognitive neuroscience perspective. Many of the studies ongoing in the lab are focused on providing answers to questions about the sequence and timing of neural events that underlie the perceptual and cognitive processes involved in visual word comprehension. This research has three specific aims. The first is to test and elaborate on predictions of the Bi-modal Interactive Activation Model (BIAM) of word comprehension in competent adult users of language. While models like the BIAM have been touted as neurally plausible, relatively little work using cognitive neuroscience methods has actually attempted to test the predictions of such models. A second complementary aim focuses on improving the precision of ERP measures of word processing by providing a better understanding of their relationship with the perceptual, cognitive and linguistic processes they are hypothesized to reflect. A third aim seeks to improve our understanding of word comprehension by examining how comprehension processes develop over time. In one group of studies we are using masked priming in normal young adults. This paradigm has allowed us to isolate four temporally overlapping ERP effects that we have hypothesized are sensitive to a cascade of word comprehension processes. We are currently testing predictions about the processing nature and timing of these ERP effects and plan to use these ERP effects to test predictions generated by the BIAM. A second group of ongoing studies include single word experiments, also in young adults, where a number of variables are manipulated that have previously been suggested to influence early visual word comprehension processes. We have hypothesize that previous failures to see effects with these variables were due to lack of power. A final group of studies will include word comprehension experiments modeled on the young adult studies mentioned above. These will be run in five groups of children between 7 and 11 years of age. The point of these experiments is to allow us to examine the development of visual word comprehension over time and thus better characterize changes in some of the neural/cognitive processes involved in reading. One long term goal is to extend these studies to children and adults with word processing and other language/cognitive deficits.

This research is supported by a grant from the National Institute of Child Health and Development, HD25889.

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Bilingualism and Second Language Learning

    In most of the world, bilingualism is the norm.  Even in the US, a primarily monolingual society, there is a growing awareness that knowledge of a second language is essential to our competitiveness in an increasingly interactive world.  However, there are a number of issues concerning the cognitive and neural systems that underlie monolingual and bilingual language use that remain unresolved.  This research focuses on one specific but critical component of the mechanisms involved in being bilingual-the cognitive and neural processes involved in acquiring and using a vocabulary in a second language (L2).  Using both behavioral and electrophysiological (ERP) techniques, our aim is to plot the cognitive and neural consequences of vocabulary acquisition in a foreign language by examining various stages of L2 language learning in both cross-sectional and longitudinal samples.  Behavioral data allows this research to be linked with the large amount of prior behavioral research on these and similar issues; ERP data will allow both quantitative and qualitative changes in the processing of L2 words to be tracked as a function of proficiency with the high degree of temporal accuracy associated with ERPs. 

 Subject Populations
    An important and unique aspect of this proposal is the plan to test two complementary populations of bilingual participants: English native speakers learning French at Tufts University in the Boston area, and French native speakers learning English at the Université de Provence in Aix-en-Provence and Marseille, France. Subjects at different stages of language acquisition will be tested in parallel experiments in order to track the changes occurring cognitively and neurally as proficiency increases. This means that the we will be engaged in recruitment of English native speakers who are also students of French, on the Boston side, as well as the recruitment of French native speakers who are students of English in France. The research on the French side is carried out in the Laboratoire de Psychololgie Cognitive under the direction of Jonathan Grainger, Ph.D.

This research is supported by a grant from the National Institute of Child Health and Development, HD043251.

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Language and Psychopathology

    This project is in collaboration with Gina Kuperberg, M.D., PhD. associate professor at Tufts University and assistant professor at Harvard Medical School.

            http://www.nmr.mgh.harvard.edu/kuperberglab/index.htm