Dr. Harris'career goals are to develop creative approaches to the study of age-related changes in the neural mechanisms underlying auditory processing. Her proposed training plan will allow her to continue her training in electrophysiology and provide additional mentorship in psychophysical and functional neuroimaging techniques. Her planned career development experiences include: a) course work, seminars, and one-on-one instruction with her mentors;and b) implementation of the mentored research plan. The new and enhanced skills Dr. Harris will acquire as a result of these activities should enable her to achieve her long-term career goal as a productive independent investigator. The proposed research project focuses on the interrelationships between age-related changes in auditory and cognitive function and their contributions to changes in communication abilities of older adults. Most previous studies of temporal processing have focused on behavioral measures, which may be affected by age-related declines in both auditory and cognitive functions. A strength of the current studies is the integration of behavioral, electrophysiological, and functional neuroimaging measures within the same subjects to disentangle the effects of central auditory and cognitive changes in the aging brain.
Three specific aims are proposed to test the hypothesis that declines in auditory temporal processing in older adults can be attributed to age-related deficits in the central auditory systems, and changes in cognitive functions, such as attention. The proposed experiments adapt a gap detection paradigm typically used in behavioral experiments to electrophysiologic and functional neuroimaging studies. From a clinical standpoint, understanding temporal resolution in the auditory system and its underlying neural processes may help explain the large variance in speech understanding in older adults. Furthermore, knowledge of the auditory and cognitive factors contributing to declines in auditory temporal processing is critical for the development of evidence-based and theory-based intervention strategies designed to improve communication by older adults.
|Harris, Kelly C; Vaden Jr, Kenneth I; Dubno, Judy R (2014) Auditory-evoked cortical activity: contribution of brain noise, phase locking, and spectral power. J Basic Clin Physiol Pharmacol 25:277-84|
|Harris, Kelly C; Wilson, Sara; Eckert, Mark A et al. (2012) Human evoked cortical activity to silent gaps in noise: effects of age, attention, and cortical processing speed. Ear Hear 33:330-9|
|Harris, Kelly C; Eckert, Mark A; Ahlstrom, Jayne B et al. (2010) Age-related differences in gap detection: effects of task difficulty and cognitive ability. Hear Res 264:21-9|
|Eckert, Mark A; Keren, Noam I; Roberts, Donna R et al. (2010) Age-related changes in processing speed: unique contributions of cerebellar and prefrontal cortex. Front Hum Neurosci 4:10|
|Harris, Kelly C; Dubno, Judy R; Keren, Noam I et al. (2009) Speech recognition in younger and older adults: a dependency on low-level auditory cortex. J Neurosci 29:6078-87|
|Keren, Noam I; Lozar, Carl T; Harris, Kelly C et al. (2009) In vivo mapping of the human locus coeruleus. Neuroimage 47:1261-7|
|Harris, Kelly C; Mills, John H; He, Ning-Ji et al. (2008) Age-related differences in sensitivity to small changes in frequency assessed with cortical evoked potentials. Hear Res 243:47-56|