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- Creators: Dixon, Maria
- Creators: Harrington Bioengineering Program
- Creators: College of Health Solutions
- Resource Type: Text
The distinctions between the neural resources supporting speech and music comprehension have long been studied using contexts like aphasia and amusia, and neuroimaging in control subjects. While many models have emerged to describe the different networks uniquely recruited in response to speech and music stimuli, there are still many questions, especially regarding left-hemispheric strokes that disrupt typical speech-processing brain networks, and how musical training might affect the brain networks recruited for speech after a stroke. Thus, our study aims to explore some questions related to the above topics. We collected task-based functional MRI data from 12 subjects who previously experienced a left-hemispheric stroke. Subjects listened to blocks of spoken sentences and novel piano melodies during scanning to examine the differences in brain activations in response to speech and music. We hypothesized that speech stimuli would activate right frontal regions, and music stimuli would activate the right superior temporal regions more than speech (both findings not seen in previous studies of control subjects), as a result of functional changes in the brain, following the left-hemispheric stroke and particularly the loss of functionality in the left temporal lobe. We also hypothesized that the music stimuli would cause a stronger activation in right temporal cortex for participants who have had musical training than those who have not. Our results indicate that speech stimuli compared to rest activated the anterior superior temporal gyrus bilaterally and activated the right inferior frontal lobe. Music stimuli compared to rest did not activate the brain bilaterally, but rather only activated the right middle temporal gyrus. When the group analysis was performed with music experience as a covariate, we found that musical training did not affect activations to music stimuli specifically, but there was greater right hemisphere activation in several regions in response to speech stimuli as a function of more years of musical training. The results of the study agree with our hypotheses regarding the functional changes in the brain, but they conflict with our hypothesis about musical expertise. Overall, the study has generated interesting starting points for further explorations of how musical neural resources may be recruited for speech processing after damage to typical language networks.
We describe a secondary analysis of an in vitro experiment that supports the capabilities of a relatively new imaging technique known as functional Magnetic Resonance Electrical Impedance Tomography (fMREIT) to detect conductivity changes in neural tissue caused by activity. Methods: Magnetic Resonance (MR) phase data of active Aplysia ganglia tissue in artificial seawater (ASW) were collected before and after exposure to an excitotoxin using two different imaging current strengths, and these data were then used to reconstruct conductivity changes throughout the tissue. Results: We found that increases in neural activity led to significant increases in imaged conductivity when using high imaging currents, but these differences in conductivity were not seen in regions that did not contain neural tissue nor in data where there were no differences in neural activity. Conclusion: We conclude that the analysis presented here supports fMREIT as a contrast technique capable of imaging neural activity in live tissue more directly than functional imaging methods such as BOLD fMRI.
Early identification of dyslexia is essential to providing children with the necessary services and support to succeed academically. Current dyslexia screening measures are not widely available for English-speaking monolingual children and those available for bilingual children are not widely used. To contribute to the effort to provide widely available screening for six-year-old English speaking and bilingual children, the ASU Bilingual Language and Literacy Lab, the Child Language and Literacy Lab, Learning to Soar Tutoring, Healing Hearts Pediatrics, and the Phoenix Children’s hospital have collaborated to develop the Dyslexia Screening Questionnaire (DysQ) that is offered in both English and Spanish. The goal of this study (Phase I) was to test the readability and comprehensibility of the DySQ to help ensure that it is accessible to a wide population of English and Spanish-speaking parents. In the second phase of the study, we aim to validate the DySQ by comparing the DySQ results with gold-standard testing for diagnosing dyslexia. The ultimate goal is to implement the DySQ into pediatric settings so that English and Spanish-speaking children may be screened for dyslexia at their 6-year-old well-child check-up.