The language comprehension research performed in the lab focuses primarily on syntactic processing. One theoretical contribution of our language research has been to develop a more precise characterization of the contribution of the left inferior frontal gyrus, often referred to as Broca’s area, to comprehension. In an earlier study (Newman et al., 2003a) we observed the differential activation of two subregions of Broca’s area, Brodmann’s areas (BA) 44 and 45 during sentence processing and hypothesized that BA 44 was more closely related to syntactic processes while BA 45 was more closely related to semantic processes. Our research team has conducted additional studies (e.g., Lee & Newman, 2010; Newman et al., 2009a, b) that have confirmed and expanded that hypothesis.
We have also begun to investigate the syntax/semantics interface. There the work has focused primarily on the influence of semantics on syntactic analysis with the underlying assumption being that given the intent of language is to transfer information (meaning), semantics has a much larger impact on sentence comprehension processes than many of the syntax-first linguistic theories have suggested.
Finally, we are also interested in the study of language impaired groups. In particular we have ongoing projects to investigate dyslexia.
We are especially interested in executive control processes such as planning and working memory. Ongoing projects in the lab use the Tower of London (TOL) spatial task and verbal reasoning tasks to explore these executive control processes. We have been particularly interested in the neural network that supports planning. While planning is a complex process that is thought to involve the prefrontal cortex, a full characterization of the network has yet to be articulated. In a 2003 paper examining the TOL task we used fMRI and computational modeling to help provide such a characterization. We were specifically interested in the differential role of the left and right prefrontal cortex and tested the hypothesis that the right prefrontal cortex was involved in plan generation while the left prefrontal cortex was involved in the control processes necessary for plan execution (Newman et al., 2003b). The results of that study along with a recent follow-up study (Newman et al., 2009c) supported this hypothesis.
Our interests in problem-solving have evolved somewhat. Recently we have investigated more mathematical problem-solving and have begun to focus on strategy differences observed across participants and how those strategy differences may affect problem-solving performance. In addition, we have explored the embodiment of arithmetic as well as the influence of emotion on problem solving performance.
A thread that runs through all of my work is the examination of individual differences. Although it has been demonstrated that there is variability in the performance of complex tasks this variability is seldom accommodated in theories. The possibility of significant individual differences in underlying processes significantly weakens the conclusions one can make from contemporary experimental procedures, in which data from a group of participants are averaged. Ignoring effects of individual differences may significantly limit scientific advances in the study of cognition, generally, and cognitive neuroscience in particular. One example of how individual differences can affect neuroimaging data can be found in a recent study we conducted (Newman et al., 2009b) in which participants were asked to read sentences of varying syntactic complexity. There, based on the debriefing questionnaire, we found reading strategy differences and these reported strategy differences corresponded to significant differences in activation in key language processing regions including Broca’s and Wernicke’s areas. These differences demonstrate the type of information that is lost when the individual characteristics of the participants are not taken into consideration. The study of individual differences is very important and it has to be the direction in which both cognitive and neuroscience research goes. By examining how and also why individuals show differences in performance and brain activation we will raise the standard on research in neuroimaging – moving beyond aggregating across individuals with potentially different functional systems and strategies -- to understanding how individual minds work.
The Department of Psychological and Brain
Last Updated 08/17/2011