Barrett, The Honors College Thesis/Creative Project Collection

Animals encounter information from different resources simultaneously, integrating input from multiple sensory systems before responding behaviorally. When different cues interact with one another, they may enhance, diminish, or have no impact on their responses. In this project, we test how the presence of chemical cues affect the perception of visual cues. Zebrafish (Danio rerio) often use both chemical cues and visual cues to communicate with shoal mates, to assess predation risk, and to locate food. For example, zebrafish rely on both olfactory cues and visual cues for kin recognition, and they frequently use both chemical and visual cues to search for and to capture prey. In zebrafish, the terminal nerve (TN) constitutes the olfacto-visual centrifugal pathway and connects the olfactory bulb with the retina, thus allowing olfactory perception also to activate visual receptors. Past studies have found that the presence of an olfactory cue can modulate visual sensitivity in zebrafish through the terminal nerve pathway. Alternatively, given that zebrafish are highly social, the presence of social chemical cues may distract individuals from responding to other visual cues, such as food and predator visual cues. Foraging and predator chemical cues, including chemical food cues and alarm cues, may also distract individuals from responding to non-essential visual cues. Here, we test whether the response to a visual cue either increases or decreases when presented in concert with alanine, an amino acid that represents the olfactory cues of zebrafish prey. We found that the presence of chemical cues did not affect whether zebrafish responded to visual cues, but that the fish took longer to respond to visual cues when chemical cues were also present. These findings suggest that different aspects of behavior could be affected by the interaction between sensory modalities. We also found that this impact of delayed response was significant only when the visual cue<br/>was weak compared to the strength of the chemical cue, suggesting that the salience of interacting cues may also have an influence on determining the outcomes of the interactions. Overall, the interactive effects of chemicals on an animal’s response to visual cues may also have wide-ranging impacts on behavior including foraging, mating, and evading predators, and the interaction of cues may affect different aspects of the same behavior.

Motor learning is the process of improving task execution according to some measure of performance. This can be divided into skill learning, a model-free process, and adaptation, a model-based process. Prior studies have indicated that adaptation results from two complementary learning systems with parallel organization. This report attempted to answer the question of whether a similar interaction leads to savings, a model-free process that is described as faster relearning when experiencing something familiar. This was tested in a two-week reaching task conducted on a robotic arm capable of perturbing movements. The task was designed so that the two sessions differed in their history of errors. By measuring the change in the learning rate, the savings was determined at various points. The results showed that the history of errors successfully modulated savings. Thus, this supports the notion that the two complementary systems interact to develop savings. Additionally, this report was part of a larger study that will explore the organizational structure of the complementary systems as well as the neural basis of this motor learning.

Studies of animal contests often focus solely on a single static measurement of fighting ability, such as the size or the strength of the individual. However, recent studies have highlighted the importance of individual variation in the dynamic behaviors used during a fight, such as, assessment strategies, decision making, and fine motor control, as being strong predictors of the outcome of aggression. Here, I combined morphological and behavioral data to discover how these features interact during aggressing interactions in male virile crayfish, Faxonius virilis. I predicted that individual variation in behavioral skill for decision making (i.e., number of strikes thrown), would determine the outcome of contest success in addition to morphological measurements (e.g. body size, relative claw size). To evaluate this prediction, I filmed staged territorial interactions between male F. virilis and later analyzed trial behaviors (e.g. strike, pinches, and bout time) and aggressive outcomes. I found very little support for skill to predict win/loss outcome in trials. Instead, I found that larger crayfish engaged in aggression for longer compared to smaller crayfish, but that larger crayfish did not engage in a greater number of claw strikes or pinches when controlling for encounter duration. Future studies should continue to investigate the role of skill, by using finer-scale techniques such as 3D tracking software, which could track advanced measurements (e.g. speed, angle, and movement efficiency). Such studies would provide a more comprehensive understanding of the relative influence of fighting skill technique on territorial contests.

The purpose of this project was to research the expression of Autism Spectrum Disorder in children and create a children’s book that can help the peers of individuals with a diagnosis to understand what the disorder entails and potentially gain a new sense of empathy for peers of all levels of physical and mental abilities. The research component includes interviews with individuals deemed knowledgeable about ASD, including occupational therapists, behavioral analysts, and parents, as well as a literature review of research studies on the expression of Autism in children. This written portion of the project may also serve as a manual for individuals who have little to no knowledge of ASD, as it dives deeper into the content of the book and research, while remaining easily understandable and clear to those without any prior knowledge or experience with ASD. It could prove especially useful for those in professions that come into contact with individuals with Autism, but do not necessarily require psychology courses or training as a prerequisite for the role, such as teachers and some health professionals.

Families of students with disabilities and those who are culturally and linguistically diverse (CLD), are looking for better educational opportunities. Charter schools offer promise as they were designed to promote student learning with limited control from the state. Charter schools though, have been criticized for relying on exclusionary discipline policies that affect CLD students and students with disabilities disproportionately. This study was designed to understand how Arizona charter schools use exclusionary discipline practices, with a focus on students with disabilities and CLD students. Two participants, a fourth grade and fifth grade teacher from a Phoenix metropolis charter school completed surveys and interviews where they answered questions about their classroom and their school’s discipline policies. Teachers were asked how they have adapted and administered classroom discipline policies and to what extent have positive behavioral strategies been implemented in an online setting due to the COVID-19 pandemic when schools transitioned to virtual learning. The results showed that in a virtual setting, teachers retained the practice of removing students from the “classroom”, expectations had to be modified to meet the needs of the new environment, and the school counselor served in conflicting roles. The findings suggested that charter schools and teachers may be transferring and adapting their reliance on exclusionary discipline practices even for an online setting with classrooms that have students with disabilities and those who are CLD.