Simon J. Fischer-Baum, Ph.D. - US grants

Project Summary/Abstract Many survivors of a left-hemisphere stroke are impaired at reading, at least immediately following the stroke. Reading impairments have a profound impact on one's well being. Reading typically improves over years following the stroke, though some degree of impairment remains common. Improvements in reading during recovery are thought to depend on neural plasticity, or the damaged brain reorganizing to better support the impaired reading functions. The long-term objective of our research is to characterize this neural plasticity so that we can develop new interventions that will enhance the recovery of reading following stroke. The immediate goal is to map this neural plasticity using functional neuroimaging, comparing a group of patients with reading impairments following stroke to controls, with the following three aims. Aim 1: We will investigate the extent to which there are consistent patterns of activation during reading tasks that distinguish individuals with reading impairments following stroke from control participants. Aim 2: We will use functional magnetic resonance imaging (fMRI) decoding methods to determine whether patients and controls differ in what different parts of the brain are doing functionally. Neural plasticity has been argued to either reflect functional take-over, whereby the function previously performed by a damaged area is shifted to a different brain region, or reflect a compensatory masquerade, i.e., the refinement of an intact cognitive process not normally used to perform a task. To determine which type of neural plasticity is occurring in the reading network, new fMRI analysis techniques are needed that go beyond activity magnitude investigations of brain regions to decode the information present in the distributed patterns of activation. We will develop such techniques and apply them to our sample to determine the extent to which individuals with chronic reading problems show consistent types of neural plasticity. Aim 3: Increases in neuronal activation to language tasks are often observed in unexpected regions with brain damaged participants. Little is known about what function these regions serve for patients during their recovery. Using the methods developed in Aim 2, we will investigate the function of these additional activated regions in our sample. The proposed research will make progress towards characterizing the nature of neural plasticity in the reading system following stroke, including an innovative approach for investigating what shifts in the neuronal activation profile of patients means in terms of changes in cognitive function. This research will provide key preliminary data to support a R01 grant application that will further elucidate how patterns of neural plasticity might differ among participants depending on lesion location or behavioral impairment, mapping these changes longitudinally across the acute through chronic phases of stroke and delineating neural plasticity in response to specific treatments. The proposed project builds on the PI's solid track record of research in cognitive theories of reading, investigations of individuals with acquired written language impairments, and use of innovative, theoretically grounded analysis tools for fMRI data.

The Planning Grants for Engineering Research Centers competition was run as a pilot solicitation within the ERC program. Planning grants are not required as part of the full ERC competition, but intended to build capacity among teams to plan for convergent, center-scale engineering research.

The sense of hearing is a critically important ability that enables an individual to relate to the external world. Loss of hearing affects an individual?s health, function, quality of life and mortality. Current estimates are that hearing loss results in excess medical costs ranging from $3.3 to $12.8B in the United States, and over $750B worldwide. A recent report from the National Academies highlighted the need to recognize hearing loss as a major public health concern. This planning grant brings together a diverse team of researchers from Rice University, Baylor College of Medicine, the University of Southern California and Oregon Health Science University. This team will have complementary expertise in auditory neuroscience, cochlear implants, speech perception and devices that connect directly to neurons. This team will engage in a series of meeting and activities that will lay the foundation for an Engineering Research Center in Auditory Bioengineering. The proposed Center will work to develop new technologies, expand the engineering workforce and foster a culture of diversity and inclusion by supporting the deaf and hard of hearing, especially members of underserved populations. At the scientific level, the engineering advances in technologies for precise electrical stimulation of neurons will be broadly applicable to devices such as retinal implants, auditory implants and deep brain stimulators.

Recognizing the limitations of hearing aids and cochlear implants, the planning team will seek to revolutionize current hearing rehabilitative technology through transformative engineering enabled by a convergent approach involving several engineering disciplines. The major scientific goal will be to develop a next generation auditory implant that more intimately connects to spiral ganglion cells, more faithfully encodes sound, is smaller and easier to use, and is more economical. During the course of this grant, the planning team will critically evaluate the potential of recent technological advances to improve hearing health care and identify additional participants to perform center-scale research. This will be accomplished through a series of meetings held in in Houston, TX, Los Angeles, CA and Portland, OR. The team will engage stakeholders - including individuals with cochlear implants, hearing health care professionals, policy makers in hearing health care, and low-income individuals whose hearing health care needs are currently unmet. The team will used evidence-based strategies to recruit and develop the center leadership team. The team will also engage major cochlear implant manufacturers and identify other industrial partners.
The intellectual focus of this proposal will reside in a critical evaluation of the potential for the following thrust areas to serve as a foundation for convergent research in Auditory Bioengineering. Thrust 1: Enabling Technologies for Next Generation Auditory Implants. In this thrust, recent advances in engineering technologies such as carbon nanofiber electrodes for neural interfacing will be integrated into biomedical microsystems to produce an innovative design for a next generation auditory implant. Thrust 2: Speech Perception for Auditory Bioengineering. In this thrust, recent advances the cognitive aspects of speech perception will be harnessed to determine the relevant information that needs to be passed to auditory implants and how best to provide that information based on what is known about the neural code, with consideration that different languages are tuned to different acoustic features. Thrust 3: Global Health and Disparities Research in Auditory Rehabilitation. This thrust will seek to investigate and evaluate ways to expand access to auditory rehabilitation with hearing aids and cochlear implants, especially for underserved population.
The goal will be to develop an ERC in Auditory Bioengineering that will serve a national resource for auditory researchers, neuroengineers, audiologists and clinicians. With a central location in Houston, TX, the center will have national outreach and serve as a way to pool patient populations for studies on outcomes and disparities in auditory rehabilitation. This proposal will fill a key need in workforce development in training more students at the interface of hearing and speech research, who are prepared to employ modern engineering approaches for auditory rehabilitation.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.