This protocol is designed to acquire an understanding of the underlying cognitive mechanisms involved in various aspects of discourse processing. The primary focus of studies has been on understanding the role of the prefrontal cortex in discourse processes, and specifically the role of the cognitive mechanism of suppression that allows selection of appropriate meanings when information is ambiguous during text comprehension. A range of experimental on-line tasks have been developed to investigate the processing of lexical ambiguities, inferential ambiguities, thematic aspects of stories, and relational language concepts presented either in pictorial (visual analogue) or proposotional (textual) representations. This fiscal year, we have run approximately 30 subjects with prefrontal cortex damage either from penetrating head injury, stroke, tumor resection, or frontotemporal dementia. Accomplishments this year include publication of our findings in in journal, European Journal of Neurology, recent submission of two other manucripts to the journal, Brain and Language, publication of 2 abstracts, 2 posters, and 5 scientific presentations. Our findings are providing evidence that supports the role of the prefrontal cortex in context-sensitive suppression function as necessary for text comprehension. In addition, lateralization of prefrontal cortex function has been found, with left lateralization dominance for processing lexical ambiguities, and right lateralization dominance for processing inferential ambiguities.
| Frattali, C; Duffy, J R; Litvan, I et al. (2003) Yes/no reversals as neurobehavioral sequela: a disorder of language, praxis, or inhibitory control? Eur J Neurol 10:103-6 |
