CURRENT PROJECTS

Influence of Inhibitory Skills on Speech Perception 
Difficulty with word finding (also known as anomia) is one of the most common deficits that people with acquired language disorders experience. Theoretical accounts of spoken word production suggest that there is competition among related words during word retrieval, and errors arise when a competing word is mistakenly selected for production. In order for the intended word to be produced accurately, all competing non-target words (called “neighbors”) must be suppressed or inhibited. The extent to which this language-specific task relies on the domain-general cognitive ability of inhibition remains unknown. This study explores whether individual differences in general inhibitory control as measured by psychological tests like the Flanker task or the Stroop task, influence language processing.

Advisor: Dr. Susannah Levi
Committee: Dr. Adam Buchwald, Dr. David Poeppel

Using Feedback Frequency to Promote Speech Motor Learning
Previous studies of limb motor learning have identified a set of principles for structuring practice that can enhance a person’s ability to learn motor skills (i.e., principles of motor learning). One parameter that can affect motor learning is how often feedback is provided during practice. Reduced feedback frequency (i.e., <100% of the time) has been shown to be advantageous for speech motor learning in intact speakers as well as in individuals with acquired impairments. However, the optimal frequency of feedback to provide the maximum benefit remains unknown. My first qualifying project systematically investigated how the amount of feedback provided during a speech motor learning task effects both acquisition and retention of speech motor skills in unimpaired speakers. While the ultimate goal of this research is to inform clinical interventions for people with motor speech impairments (e.g., dysarthria, apraxia of speech), this study includes participants with intact motor systems as a first step in understanding the impact of feedback frequency on speech motor control.

Advisor: Dr. Adam Buchwald
Committee: Dr. Tara McAllister Byun, Dr. Maria Grigos

Psycholinguistics and Aphasia Lab
I work as a research assistant in Dr. Adam Buchwald’s Psycholinguistics, Aphasia and Neuromodulation Lab. For a description of our projects please visit our lab homepage.

PREVIOUS PROJECTS

MEG Analysis of Face Processing
As part of a class project, I became involved in a MEG study about the phenomenon of ‘face-selectivity.’ Face-selectivity has been a major focus in the study of visual face perception, yet despite much research, the nature of the neural mechanisms underlying this phenomenon remains unclear. One major area of debate is whether perception of  faces relies on holistic processing or if facial information is processed by feature (e.g., by individual components of the face). The main goal of this experiment was to determine whether and to what extent early occipitotemporal responses reflect face-selectivity, and whether the selectivity is holistic or feature based. To do so, we examined effects of holistic and feature-based primes on M100 and M170 responses to Mooney faces and houses. Our findings were published in Frontiers in Psychology in 2016.

Co-Investigator: Gwyneth Lewis
Advisor: Dr. David Poeppel

Fluency and Speech Rate in Epilepsy: Correlations with fMRI Profiles
I completed my Master’s thesis in 2010 which examined speech fluency and neuroimaging profiles of children with and without seizure disorder.  Fluency and speech rate were analyzed in narratives produced by 26 children (ages 4-12) with epilepsy and 26 matched peers. These measures were also regressed on fMRI activation data collected while the children participated in a receptive language task. Children with epilepsy were found to be significantly more disfluent during their narrative productions than their matched typically developing peers. Additionally, regression analyses revealed that working memory regions may be recruited in children with higher levels of disfluency, regardless of diagnostic group, due to increased processing demands during language comprehension. This study adds to an emerging literature that has found depressed language skills in children with chronic seizure disorder and contributes to the growing literature that suggests that disfluency during spoken language tasks may be a subtle marker of expressive language impairment.

Advisor: Dr. Nan Bernstein Ratner
Committee/Contributors: Dr. Rochelle Newman, Dr. Madison Berl, Dr. William Gaillard,  Dr. Yasmeen Shah

Language Development and Perception
While completing my masters degree at the University of Maryland, I worked as a graduate research assistant in Dr. Rochelle Newman’s Language Development and Perception Lab. My responsibilities included recruiting participants, as well as collecting and analyzing data for various studies relating to language development and speech perception primarily in infants and young children. For a description of Dr. Newman’s current projects please visit her lab webpage.

Defining Phenotypes within the Autism Spectrum
I worked as a lab manager and research assistant for two years under the supervision of Dr. Valerie Hu in the Department of Biochemistry and Molecular Biology at the George Washington University. Dr. Hu’s lab analyzes the biological and genetic factors contributing to Autism Spectrum Disorders (ASD) using a systems approach which includes integrative genomics coupled with phenotyping of subjects.

Heterogenity in phenotypic presentation of ASD has been cited as one explanation for the difficulty in pinpointing specific genes involved in autism. In an effort to reduce the “nosie” in genetic data, my project focused on using multiple clustering algorithms to identify subgroups of children with autism with clinically relevant behavioral phenotypes on the basis of item scores from the Autism Diagnostic Interivew-Revised (ADI-R) diagnostic instrument. These subgroups were found to be associated with distinct gene expression profiles. Our findings from the clustering analysis, as well as the subsequent gene expression profile analyses, were published in the journal Autism Research in 2009.

For more information about Dr. Hu’s current studies, please see her webpage.