Inter-individual differences in overall language proficiency can be related to one's level of language comprehension, but moment-to-moment changes in attention may also explain within-subject variation in language competence. In contrast to what is known about the cortical systems involved in reading, the neural mechanisms governing attentional modulation of verbal language-processing networks are not well understood. This Mentored Research Scientist Development Award is intended to help fill this gap by providing the candidate with a structured plan for career development in two major fields of biomedical research that represent new career directions: brain mechanisms of language, and the use of contemporary functional imaging technologies to study language processing. The ultimate goal is to augment the candidate's extensive background in systems physiology using animal models and to foster his professional development in the specific areas of verbal language processing, reciprocal interactions between memory and attention networks, and the modulation of functional connectivity between these brain systems. His systems perspective and broad knowledge of the neural basis for behavior can help fill a critical need in our imaging community to develop testable functional models of effective connectivity between the distributed brain networks involved in bottom-up and top-down attentional control of human language processing. The research plan will take advantage of state-of-the-art fMRI facilities at the University of Arizona (UA) to investigate a little-studied area of human neuroscience: cortical and subcortical mechanisms linking language, attention, and memory. The training and research experience provided by this K01 award will enable the candidate's successful transition from basic research in learning &memory, systems physiology and animal communication to a career as an independent scientist studying the functional neural architecture of attentional control over auditory learning and language processing, using non-invasive biomedical imaging tools as the primary means of data collection. Relevance: The attention system governs how the brain selects only some information from the environment and admits it to consciousness, enabling us to focus awareness on objects and events that are relevant to our immediate goals. However, the limited capacity of the attention system varies greatly between individuals and under different cognitive loads. Attention is also a crucial cognitive component in many disorders affecting language, including schizophrenia, ADHD, specific language impairments, and language learning disabilities (LLD), but what roles attention plays in the expression of these complex spectrum disorders is not well understood. Therefore, in parallel to normal language processing, we will also examine patients with LLD and/or ADHD to explore specific models of functional connectivity and modulation in the brain using high-field fMRI.
|Christensen, Thomas A; Almryde, Kyle R; Fidler, Lesley J et al. (2012) Modulating the focus of attention for spoken words at encoding affects frontoparietal activation for incidental verbal memory. Int J Biomed Imaging 2012:579786|
|Christensen, Thomas A; Lockwood, Julie L; Almryde, Kyle R et al. (2011) Neural substrates of attentive listening assessed with a novel auditory Stroop task. Front Hum Neurosci 4:236|
|Christensen, Thomas A; Antonucci, Sharon M; Lockwood, Julie L et al. (2008) Cortical and subcortical contributions to the attentive processing of speech. Neuroreport 19:1101-5|