Dyslexia is a prevalent developmental disorder characterized by unexpected reading difficulty in children and adults with otherwise normal IQ and intelligence. Dyslexia is a heterogeneous disorder and a variety of deficits are observed in the population, with auditory perception and rapid stimulus processing occurring most frequently. Genetic variants are likely related to this heterogeneity. One such gene that has been reliably linked to dyslexia is the neural migration gene DCDC2. Suppression of this gene in a rat model dramatically impairs speech-sound discrimination ability from a stream of rapidly-presented auditory stimuli (Centanni et al., 2016), suggesting a potential role for this gene in rapid stimulus processing deficits in humans and supporting a prior study linking this gene to reading speed (Neef et al., 2017). One potential casualty of processing speed impairments is the ability to process unpredictable stimuli. In the current study, we designed a rapid speech sound discrimination and prediction task to evaluate whether the rapid speech sound impairment previously linked with Dcdc2 also causes deficits on a prediction task. If increased presentation rate impairs the ability to process unpredictable stimuli, then the addition of a stable predictor sound should improve performance. To test this hypothesis, homozygous Dcdc2-knockout, heterozygous, and wild type rats were trained to respond to a target sound /dad/ in a stream of rapidly presented distractors in the presence or absence of a predictor sound /bad/, which occurred reliably prior to the target in 40% of trials. In wild type rats, the results indicate the presence of a predictor enhances response to the target /dad/ at low speeds, but as the stimulus presentation rate increased the rats began responding to the predictor /bad/ rather than the target. I will present these findings as well as pilot data from rats with Dcdc2 knockout to investigate the role of this gene on the response to a stable predictor.

A recent study (Petursdottir & Oliveira, accepted pending revision) found that when comparing equivalence-based instruction (EBI) to a complete instruction (CI) control condition using concurrent training and equal mastery criteria, EBI did not inherently produce faster or better learning than CI. However, this study included only a single EBI training structure. The purpose of the present experiment was to (a) evaluate the efficiency of linear series (LS) and one-to-many (OTM) EBI protocols relative to CI, and (b) to assess transfer of function following the three arrangements. Sixty undergraduate students were assigned to one of three groups (CI, EBI-OTM and EBI-LS), all of which received training to establish three 4-member stimulus classes. In the class establishment phase (ABCD training), the CI and EI groups were presented with 36 and 9 types of trials, respectively. After achieving mastery criterion, the ABCD test included all possible trial types, with no feedback. After achieving criterion on the ABCD test, all participants proceeded to transfer of function phase, in which they were taught to execute different motor responses to one stimulus in each class, and then tested with the remaining stimuli in each class. Results suggest the OTM protocol, but not the LS protocol, was more efficient than CI. The three groups performed equally well on the transfer-of-function test.

Language learning in adulthood is often important for personal or vocational reasons, but learning a second language after the sensitive period ends is time-consuming and retention is difficult. Research has suggested that cervical vagus nerve stimulation (cVNS) can help to improve cognitive function (Sjogren et, al. 2002) and working memory in patients (Sun et al., 2017). Transcutaneous auricular vagus nerve stimulation (taVNS), a less invasive method, activates similar brain structures as cVNS (Yakunina, Kim, & Nam, 2016). Recently, our lab demonstrated that taVNS paired with training improved letter-sound learning in typically-developing young adults (Thakkar et al., under review). The current study was designed to evaluate this approach in language learning. During a training session, they were exposed to 30 words in Palau, their English translations, and a picture that corresponded to the word while receiving either active or sham stimulation to the outer left ear. Each stimulus was repeated 10 times. At the end of training, a free-recall test was given where participants saw a trained word and provided the English translation. After one week, participants completed the same free-recall test of English translations to evaluate retention of the 30 trained words. While data collection is still in progress, we are seeing trends in the hypothesized direction such that those receiving active stimulation recall more words after training and at retention than those receiving sham stimulation.

Adopted children often have trauma–related emotional and behavioral problems, such as depression, anger, and anxiety, and these problems can continue to exist after adoption. Post-adoption, the adoptive family’s impact on these problems is not well understood. The current study examines the relationship between adopted children’s trauma symptoms and family communication – a construct that is associated with child social-emotional adjustment in traditional, biological families. Data was collected from adoptive families who were recruited to participate in a therapeutic family intervention. The results revealed a significant negative correlation between family communication and trauma-related emotional and behavioral problems in adopted children; specifically, the healthier the family communicated, the less problems the adopted child exhibited. Further, we wanted to determine if a similar relationship was found between biological children’s emotional problems in adoptive families and family communication. The results revealed a similar relationship: the healthier the family communicated, the less emotional problems the biological children experienced. The results of this study indicate that family communication may be a significant factor when considering the severity of adopted children’s trauma-related emotional and behavioral problems post-adoption.

As the threat of antimicrobial-resistant infections continues to rise, the need for novel antibiotics grows. Targeting virulence factors in bacterial pathogens is one potential strategy for antibiotic development because inhibiting virulence would decrease the ability of the pathogen to evade the host immune response. This strategy may decrease the development of resistance since the treatment is not directly bactericidal and there is less selective pressure put on the bacteria population. Our goal is to discover new virulence genes in Bacillus anthracis that could potentially be a therapeutic target. Specifically, we are interested in finding genes that allow B. anthracis to acquire iron from the host. For bacterial pathogens, iron is critical for growth and often a limiting nutrient in the host. It has been linked with proper functioning of electron transfer proteins and superoxide dismutase enzymes. In B. anthracis infection, iron is acquired from host hemoglobin through a hemolytic pathway, but the complete mechanism of this is unknown. Approximately 1000 transposon mutants of B. anthracis were screened for the inability to acquire iron from hemoglobin, and five were deficient in acquiring iron from hemoglobin in in vitro assays. Of those five mutant strains, only one (9F12) also exhibited an in vivo phenotype using the wax worm model of infection. The gene disrupted in the 9F12 transposon mutant is the dUTPase/aminopeptidase gene. Our aim in this study is to confirm that the disruption of the dUTPase gene leads to the inability to acquire iron from hemoglobin in B. anthracis. Using targeted mutagenesis, we created an insertional mutant strain to disrupt the dUTPase gene and we are currently testing it, along with WT and 9F12, for the ability to grow in iron-limited conditions with or without hemoglobin. Confirmation of this phenotype will demonstrate that the dUTPASE/aminopeptidase gene is important for iron acquisition from hemoglobin and will support further studies to understand the role of this gene in the virulence of B. anthracis.