Completed Honors Projects
To view a PDF document version of the abstracts for completed Undergraduate Honors projects, click on the links below that correspond to a particular school year. To view a compilation of all of the abstracts from 1998-99 to 2018-19, click here.
The text of the current school year’s abstracts (and one prior year) can also be found on this page by scrolling down past the school year links.
Undergraduate Honors Projects – 2018-2019
Neural and Behavioral Assays for Studying Predictive Coding in the Mouse Brain
Advisors: Santiago Jaramillo, PhD and Nicole Dudukovic, PhD
‘Controlled hallucination’ is a term that has been used to describe the process of interpreting sensory information according to the theory of predictive coding. This theory posits that the brain’s mechanisms for interpreting sensory information function by generating predictions about the external world and comparing these predictions to sensory signals. To assist in identifying neuronal mechanisms for how the brain generates predictions about patterns of sounds we trained mice in a head-fixed, reward-driven, behavioral task that required the animals to make predictions about incoming sounds. We then recorded sound responses and assessed frequency tuning in auditory cortical neurons in awake, head-fixed, non-behaving mice in preparation for upcoming electrophysiological experiments that will be used to evaluate the neural basis for generating predictions about sounds. In these experiments, using the classical oddball sequence and the many-standards control sequence, we plan to isolate measures of deviance detection into repetition suppression and prediction error. After investigating neuronal mechanisms for generating predictions about sounds in non-behaving mice we plan to refine our experimental paradigm and conduct recordings in behaving mice.
How the Use of Simulations Effects the Understandability and Memory for Expert Testimony
Advisor: Robert Mauro, PhD
Experts are relying increasingly on the use of computer-generated simulations, or recreations of an incident that are constructed by entering data into a computer program, to effectively communicate complex information. However, the validity of a simulation is often based on key assumptions that are obscure and hidden while the imagery is vivid and compelling. This raises the question of whether simulations can be effective ways to enhance the ability of the courts to deal with arcane information, explain complex issues in ways that judges and jurors can understand, or allow judges and jurors to be swayed by presentations that are only loosely grounded in the facts and science. In the effort to enhance the clarity and persuasiveness of expert testimony, we seek to investigate the effect of simulations on individuals’ perceptions of the validity of expert testimony. The questions guiding our inquiry are as follows: How effective are simulations relative to traditional visualizations in persuading individuals? How can simulations be effectively cross-examined? In what ways are simulations persuasive and/or being potentially mistaken for fact? To answer these questions, participants will be recruited through the University of Oregon Psychology Department human subjects pool and randomly assigned to one of three conditions based on the use of a simulation and the use of cross-examination (1. No simulation, no cross, 2. With simulation, with cross, 3. With simulation, no cross), used to measure the extent of the simulation’s persuasiveness and its effect on juror decision making.
Examining Parental Reflective Functioning and Breastfeeding Patterns
Advisor: Dare Baldwin, PhD
Motherhood is an inimitable experience in one’s life. It is viewed as a significant moment and is often considered to be the entry into adulthood. But, many women across the globe don’t feel prepared. They often experience fatigue, tiredness, depression, loneliness, powerlessness, anger and a sense of uncertainty. For many, incorporating breastfeeding as well as a myriad of other life changes (e.g., sleep patterns, work schedule, relationship changes, etc.) present serious challenges to coping and adjustment. Parental reflective functioning denotes one’s ability to perceive self and child in terms of mental states, such as feelings, desires and goals. It helps with the successful navigation of parent-child interaction. In this research, we investigate the extent to which parental reflective functioning is related to mothers’ adjustment to their breastfeeding experiences and success, in conjunction with other factors, such as depression/stress/anxiety and level of social support. Our findings will offer altogether new insight into the struggles and achievements of motherhood.
Juror Perceptions of Asian American Attorneys
Advisor: Robert Mauro, PhD
In the American judicial system, jurors are tasked with determining outcome of trials based on information presented as admissible evidence. One way in which attorneys sway jurors to decide in favor of their clients is through the telling stories that explain the facts in evidence (Findley & Sales, 2012). However, jurors may interpret these stories differently depending on the preexisting biases that they hold. The present study investigates the way in which jurors’ biases about gender and race interact with attorneys’ speech style to affect trial outcomes. We asked 119 participants (to act as mock jurors while reading a report of a hypothetical criminal trial. The participants were randomly assigned to one of eight conditions created by varying the race (Caucasian/Asian) and gender (Male/Female) of the defense attorney and the way that the defense attorneys presented their closing argument (story/legal issues). Dependent measures include verdict, culpability ratings, and attorney trait assessment. Data analyses will test for the main effects and interactions between the independent variables on the dependent measures. Implications, limitations, and future directions will be discussed.
Story Model of Juror Decision Making
Advisor: Robert Mauro, PhD
In the United States criminal justice system, juries are tasked with the most important, complex job in a criminal trial – determining the guilt or innocence of the accused. Previous research has indicated jurors’ decisions are greatly influenced by composition of attorneys’ closing statements, with preferences toward clear, understandable stories. Pennington and Hastie’s (1981) Story Model of Juror Decision Making argues that jurors reorganize trial evidence into a narrative-based sequence of events, with verdicts favoring the most easily-organized evidence. The present study seeks to expand on Pennington and Hastie’s Story Model (1981) by comparing the effectiveness of narrative-style defense closing statements and traditional, legal fact-based closing statements. In line with Pennington and Hastie’s (1981) Story Model, we hypothesized that narrative-based defense closing statements would be more likely to produce a verdict of “not-guilty” than fact-based closing statements. Additionally, we hypothesized that attorneys, regardless of race and gender, who utilized a narrative-based closing statement would receive higher ratings on measures of personal traits such as likeability, intelligence, and aggression.
Adverse Childhood Experiences and Self-Regulation in At-Risk Children: An Intergenerational Perspective
Advisors: Elizabeth Skowron, PhD; Nicole Dudukovic, PhD; and Emma Lyons, MA
Exposure to early adversity creates lasting negative effects in biological and behavioral functioning across the lifespan (Anda et al., 2006; Shonkoff & Garner, 2012; Felitti et al., 1998; Gunnar & Quevedo, 2007; Obradovic et al., 2010), such as deficits in self-regulatory abilities (Skowron, Cipriano-Essel, Gatzke-Kopp, Teti, & Ammerman, 2014). The parasympathetic nervous system (PNS), a branch of the autonomic nervous system, is key in physiological regulation and is often used to measure self-regulatory capacity. The current study examined the intergenerational impact of early adversity on self-regulatory functioning by clarifying the relationship between parents’ early adversity (ACES) and their child’s self-regulation, as measured by respiratory sinus arrhythmia (RSA). Participants (N=203) were parent-child dyads in which children were 3 to 7-years-old; families were recruited from the Department of Human Services (DHS) and the Eugene, Oregon community. RSA was measured while children were at rest and the Adverse Childhood Experience Scale (ACES) scores were used to assess the extent of adversity that children and their parents had experienced. A simple correlation analysis was run to test the relationship between parent ACES and child ACES, finding a significant positive relationship, indicating that parents who experienced childhood adversity were more likely to have children who experienced childhood adversity. A regression analysis was run to compare child ACES with child RSA, controlling for child age and gender, and no significant relationship was found. A second regression analysis was conducted to compare parent ACES with child RSA, controlling for child age, child gender, and child ACES, and no significant relationship was found. Future research should recruit a sample with a more representative distribution of ACES and should control for other potentially important variables, such as race and socioeconomic status.
Caregiver Singing and Infant Vocalizations in Everyday Life
Advisor: Caitlin Fausey, PhD
The auditory environments infants encounter impact their vocal development, especially during interactions between a caregiver and their infant (e.g., Franklin et al., 2014; Cartmill et al., 2013). We know that caregivers not only talk but also sing to their infants; however, we don’t yet know how singing might matter for many infant behaviors in everyday life (Custodero, Britto, & Brooks-Gunn, 2003). In this study, I ask: Does singing impact infant vocalizations in everyday life? We audio recorded one full day at home from 35 infants (ages 6-12 months old). Trained coders identified moments of live vocal music by listening to these recordings. Speech modeling software automatically identified infant vocalizations (Ford et al., 2008). Overall, infants encountered 6.5 minutes of live vocal music each day and vocalized 1165 times over the course of each day. Interestingly, infants who encountered more live vocal music also vocalized more. These results raise the possibility that caregiver singing promotes vocalization practice for infants.
Parsing Out Perspective Taking: Patterns in Narrative Strategies and their Impact on Social Relations
Advisor: Sara Hodges, PhD
Perspective taking is often regarded as a tool to improve social relations, but it can sometimes “backfire,” leading to negative outcomes (e.g., increased stereotyping). Past research has examined the effect of instructing people to perspective take (or not) on various outcomes but has focused less on the strategies people employ when taking another person’s perspective. To better understand what causes this “backfiring,” we asked participants to write about the typical day of an out-group target (i.e., someone who supported the opposing candidate in the 2016 U.S. Presidential Election) and then answer questions about social outcomes in relation to the target (e.g., how much they liked the target, willingness to engage in conversation with the target, and validity of the target’s position). Participants’ narratives were coded for the point of view they were written in (i.e., first-person, embedded/marked, third-person, and no point of view), the concentration of stereotypes for each political group (i.e., liberal and conservative), and average valence (i.e., negative to positive) of content. Third-person point of view was hypothesized to be the most commonly chosen point of view, but first-person was hypothesized to have the most positivity and the least stereotyping. Separate multiple regressions conducted found that smaller concentrations of stereotypes and more positive valence generally predicted better social outcomes. Liberal participants generally exhibiting greater negative perceptions of out-group relations, which could be potentially explained by bitterness over their loss in the 2016 U.S. Presidential Election. Altogether, the findings show the need for deeper understanding of the natural strategies people employ when perspective taking before perspective taking can be used to foster a more consistently effective intergroup intervention.
Olfaction and Oxytocin: Understanding Attraction/Aversion Behaviors in Mice
Advisors: Matt Smear, PhD and Marike Reimer, MS
In humans as well as mice, oxytocin is a neurotransmitter that creates social connections and bonds between members. In mice, it is involved in enhancing social recognition by modulating olfactory neural functions, while in people it is theorized that dysfunction in the oxytocin system early on in development could lead to the development of autism. Because of its link to the social and emotional brain, oxytocin is a likely candidate to moderate social behaviors. In this study, we hypothesized that oxytocin is vital for social memory and connections in mice. Using machine vision techniques, we will determine memory preferences in female mice. We will then inject a dose of oxytocin receptor antagonist, allowing us to knock out the oxytocin receptors in the granule cells of adult female mice, revealing the role of attraction and social recognition. The potential findings between oxytocin signaling and social disorders in mice explain how studying these specific underlying behavioral mechanisms may lead to new information about the nature and biological basis of certain social disorders.
Effects of Acculturation on Normative Dissociative Experiences in an East Asian Sample
Advisors: Gordon Nagayama Hall, PhD and Jennifer Lewis, MS
It has been suggested that culture influences individual differences in dissociative experiences. Previous work has indicated that people with East Asian backgrounds tend to report higher tendencies of trait dissociation than their Caucasian peers. The present study investigated normative dissociative experiences in Asian cultures and explored the roles that language and acculturation might have on these experiences. Thirty-seven international and American students with Chinese or Japanese background were recruited to complete the Dissociation Experiences Scale, as well as two measure of acculturation. Mean dissociation values of our sample were tested against a sample of Caucasian students collected from a previous study. Results did not find a significant difference in mean dissociation scores between the Caucasian sample and our Asian sample. Furthermore, behavioral acculturation and English proficiency significantly predicted dissociative levels of our sample while value acculturation did not. The present study shed light on the possible relationship between inherent behaviors in a given culture and dissociative tendencies.
Negative Valence and Associative Memory
Advisor: Dasa Zeithamova-Demircan, PhD
Our ability to create and remember associations is an essential aspect to our day-to-day lives. Previous research suggests that the ability to remember associations is impaired by negative emotions, though these findings remain inconclusive. In this study, we examined whether this impairment from exposure to a negative stimulus could be transferred to subsequent associations. Sixty-five students were recruited from the University of Oregon Psychology Department through the Human Subjects Pool. Subjects completed a paired-associates paradigm, in which they learned to link neutral object pairs (AB & BC) that shared a common associate (B). Subjects were randomly assigned to a condition in which they were exposed to either negative or neutral distractor images prior to learning each AB pair association. After being tested on AB learning, subjects then learned BC pairs, as well as unrelated pairs (XY) that did not share any AB associations. Results showed that subjects had worse memory performance for BC compared to both AB and XY pairs. However, there were no differences in learning for any of the pairs as a function of emotional distractor condition. Overall, our results suggest that irrespective of distracting emotional experiences, learning of overlapping associations is more difficult than learning of non-overlapping associations.
The Relationship between Child Baseline RSA and Critical Parenting Practices
Advisors: Elizabeth Skowron, PhD; Dare Baldwin, PhD; and Carrie Scholtes, MS
Parenting behavior has been shown to be a predictor of child self-regulation. Previous studies have demonstrated an association between supportive parenting behavior and positive child outcomes as well as an association between harsh parenting behavior and difficulties with child emotion regulation (Binion & Zalewski, 2017). Despite extensive research on emotional and behavioral self-regulation, less is known about physiological processes of self-regulation. It is important to examine self-regulation at a biological level because this measure is uninfluenced by the thoughts and emotions of the individual. The current study sought to examine pathways through which harsh and controlling parenting practices, assessed via the Conflict Tactic Scale-Parent Child (CTSPC) and three five-minute parent-child interaction tasks, impact children’s ability to physiologically self-regulate. Child physiological self-regulation was assessed using baseline resting respiratory sinus arrhythmia (RSA). An analysis of the relevant literature revealed that children whose mothers utilized more negative control during dyadic interactions exhibited deficits in their ability to self-regulate physiologically (Calkins, Smith, Gill, & Johnson, 1998; Hastings et al., 2008). Thus, we hypothesized that parents who use critical parenting practices will have children who exhibit deficits in physiological self-regulation. Contrary to our predictions, a hierarchal linear regression revealed no significant relationship between either harsh or controlling parenting and child physiological self-regulation.
The Role of Infant Attachment and Self-Efficacy in Predicting Later Academic and Social Competence
Advisors: Jennifer Ablow, PhD and Jeff Measelle, PhD
Child self-efficacy has been shown to predict better social and academic problem solving skills, both of which are foundational to school success. Additionally, attachment security has been linked to school achievement via its effect on socioemotional adjustment. Presently, few studies have addressed the interaction of self-efficacy and attachment early in life to determine whether they have a joint role in shaping readiness for school. We hypothesize that self-efficacy during infancy will predict school readiness outcomes at age 5. However, we also anticipate that this association will be moderated by infant attachment security. In particular, we expect that infants with disorganized attachment histories will fail to develop the self-efficacy capacities needed to begin school on an adaptive trajectory. Our high-risk sample comprises 72 low SES mother-infant dyads who were followed longitudinally from pregnancy through 60 months postnatally. When infants were 17-months-old they completed the Strange Situation Procedure as well as a task designed to probe early self-efficacy, which together we used to predict mother’s reports of their child’s social and academic competence at age 5, before entry to kindergarten. Contrary to our predictions attachment style and self-efficacy did not predict later academic and social competence, and there was no interaction between self-efficacy and attachment style. These findings suggest that self-efficacy is still changing and has yet to consolidate at 17 months of age. Other factors of our high risk sample, such as poverty, could have made a larger impact than attachment style on academic and social competence at 5 years, thus overshadowing the affects attachment style may have had.
Is Inhibition Dependent on Working Memory Capacity?
Advisors: Ulrich Mayr, PhD and Melissa Moss, MS
The ability to stop initiated actions is a critical component of effective self-regulation, such as resisting the urge for ‘sex, drugs, and rock and roll.’ The current dominant theory in cognitive control assumes that maintaining task-relevant information in working memory is necessary for the effective implementation of inhibitory control. In this study, we addressed the interplay of inhibitory control and working memory maintenance processes using a dual-task paradigm in which both inhibitory control demands and working memory load were manipulated. Because the standard theory predicts mutual interference between the two processes, we hypothesized that if inhibition interferes with working memory maintenance, working memory performance will be lower when participants successfully employ inhibitory control in response to a stop signal, versus when they fail to inhibit their action. Further, this interference in performance should be greatest when working memory load is high. Participants completed a combined working memory and stopping task in which stopping behavior occurred during the working memory maintenance interval. Our results showed no evidence of mutual interference between working memory load and stopping behavior on working memory performance. This result is inconsistent with the dominant view of working memory capacity as the primary constraining factor in inhibitory control. Rather, distinct processing resources may underlie these two different aspects of self-regulation.
Referential Communication Task in a Naturalistic Setting
Advisors: Dare Baldwin, PhD and Netanel Weinstein, MS
Reaching shared understanding in conversation is an important part of daily life. Various mechanisms facilitate this achievement including: the ability to engage in perspective taking, sensitivity to gaze, sharing attention, and making pragmatic inferences about an interlocutor’s intent. Prior research on this topic has prioritized experimental control over ecological validity by placing participants in highly constrained situations. We addressed these limitations in the present study by correlating performance in a modified referential communication task with participants’ performance on several standard personality and socio-cognitive measures. Specifically, pairs of participants were placed on either side of a shelf with a series of cells and prepared a cake from a given recipe card. Some of the cells on the shelf were visible to only one participant or the other, while some cells were visible to both. We measured participants use of various disambiguation strategies (e.g. gaze checking or making a clarification request) and examine whether performance on standard socio-cognitive measures predict these behaviors. This research helped shed light on the relationship between standard decontextualized socio-cognitive measures and real-life social interaction as well as the extent to which these measures predict individual differences in the way people achieve shared understanding in conversation.
The Effect of Memory Self-Efficacy on the Dynamics of Delayed Free Recall, Encoding Strategies, and Performance
Advisors: Nash Unsworth, PhD and Ashley L. Miller, MS
Memory self-efficacy (MSE), a self-assessment of one’s memory abilities, has been found to positively relate to memory performance, however, the reasons for this relationship remain unclear, particularly in the context of free recall. The current study (n = 169) examined the relationship between individual differences in MSE, the use of effective encoding strategies, and the dynamics of free recall (e.g., serial position curves, probability of first recall, conditional response probabilities, recall latencies, and inter-response times). While we found that MSE was related to encoding strategy use and overall recall performance, converging evidence from the dynamics of delayed free recall did not reveal any MSE-related differences in how individuals retrieve items from long-term memory. The results suggest that variation in performance is partially due to differences in encoding strategies but differences in MSE are also important in that they uniquely predicted recall even when taking effective encoding strategies into account.
Repetitive Negative Thinking Changes the Effect of Sleep Extension on Stress Response
Advisors: Melynda Casement, PhD and Xi Yang, MS
Insufficient sleep duration can disrupt physiological stress response systems, but the relationship between sleep and stress may depend, in part, on how stressors are perceived or interpreted. The present study investigated whether repetitive negative thinking (RNT) affects the strength of the relationship between sleep duration and parasympathetic nervous system response during rest and stress. Young adult women with symptoms of depression and insufficient sleep (n=18) were assigned to a week of extended sleep opportunity or typical sleep opportunity. Following sleep manipulation, parasympathetic activity was evaluated using high-frequently heart rate variability (HRV) during rest and exposure to a social stressor. Extended sleep opportunity increased resting HRV, but only in participants with low RNT. However, neither sleep extension nor its interaction with RNT affected reactivity to the social stressor. Future research should examine this sleep by RNT interaction with larger sample size and more statistical power.
How Does Harsh Parenting Relate to Children’s Inhibitory Control when Familial Economic Status & Subjective Social Standing are Controlled for?
Advisors: Elizabeth Skowron, PhD; Phil Fisher, PhD; and Akhila Nekkanti, MS
Inhibitory control is a rapidly developing skill during early childhood which predicts school readiness and social competence (Ponitz et al. 2009). Familial socioeconomic status, social standing, and parenting behaviors have all been shown to influence children’s’ development of this skill (Dilworth-Bart 2012; Ursache, Noble, & Blair 2015; Blair & Raver 2012). The current study examined whether harsh parenting was still a significant predictor of inhibitory control when socioeconomic status and social standing were controlled for, in 134 welfare involved children (Mage = 5.12 years, SD =1.45 years). Interestingly, within our high-risk sample, none of these were significant predictors of child inhibitory control performance on a child version of a Go-No Go task.
The Relationship between Self-Reported Mindfulness and the P300
Advisors: Don Tucker, PhD and Jennifer Lewis, MS
Mindfulness is a state of awareness that allows an individual to more effectively monitor their cognition and emotions. The ways in which mindfulness impacts aspects of cognition, including attention and attentional control, are still being researched. The current study examines how dispositional mindfulness is related to individuals’ attention and attentional control as measured through dense-array EEG (dEEG). We examined participant’s (n=72) scores on the Five Facet Mindfulness Questionnaire (FFMQ; Baer, Smith, Hopkins, Krietemeyer, & Toney, 2006) and their event-related potentials (ERPs) generated from completing the color-word Stroop task modified for dEEG recording. Response times were also recorded. ERP waveform amplitude differences for the P300, an ERP associated with attentional processes, did not significantly differ by category (i.e., Incongruent, Congruent). However, preliminary analyses showed a relationship between self-reported mindfulness and the amplitude of the P300 (across both categories), whereas higher scores on the FFMQ were associated with attenuated P300 amplitudes. Decreased P300 amplitudes may indicate the deployment of less attentional resources. It’s possible that individuals who are more mindful, have naturally increased attention and therefore require less attentional resources in a cognitively demanding task. Mindfulness has been found to be an effective intervention for mood disorders, particularly anxiety disorders (Blanck et al. 2018). Understanding the particular ways that mindfulness impacts cognition may lead to a further understanding of the mechanisms by which mindfulness improves anxiety symptoms and thus improve treatment.
Is Forgetting Good for Learning? Examining the Emergence of Abstract Rule Representations
Advisors: Ulrich Mayr, PhD and Atsushi Kikumoto, MS
Most actions are driven by abstract action rules that need to be applied to specific environmental conditions. The abstract goal to make coffee is implemented differently in your own than in your office kitchen. We examine here the degree to which improvements through practice result from (1) strengthened representations of abstract rules, from (2) better adaptation to specific environmental conditions, or from (3) representations that integrate abstract rules and specific conditions into conjunctive representations. We used a task that required the application of up to four different abstract spatial translation rules in order to respond to a given spatial stimulus. Subjects (N=46) performed an initial, 45-minute session applying two of the four rules to one of two possible stimulus configurations. During the second, 45-minute session, the two withheld abstract rules and the second stimulus configuration were introduced. To test the possibility that abstract, generalizable knowledge is fostered through consolidation or forgetting of specific conjunctive representations the second session occurred either right after the first session, or one week apart.
Results showed that it was harder to apply new rules to practice than to new stimulus configurations — a clear indication conjunctive representations between abstract rules and stimulus settings.
Importantly, this effect was substantially weakened when the new rules/stimulus settings were tested after one week. This suggests that during the 1-week delay, specific conjunctive representations were weakened (i.e., forgetting), thereby increasing the contributions of abstract rule representations. In other words, forgetting can benefit the emergence of generalizable skills.
Time Frequency Dynamics of Theta Rhythm During Self-Evaluation
Advisor: Don Tucker, PhD
In this study, we discussed some commonly used EEG preprocessing method with their pros and cons, and we used a fairly new method—joint time frequency analysis—to study the clinical significance of depression, particularly, self-evaluation. We created a subset from a larger EEG dataset including mildly depressed males and females, and more severely depressed males and females. All participants participated in a self-evaluation task where personality trait words were presented, and then behavioral responses were required based off whether the trait word is self-descriptive. Theta power was extracted for statistical analysis. From the statistical result, we found interesting electrode by task condition by sex by depression interactions from stimulus onset to 300 ms post-stimulus, and all main effects and interaction effects after 300 ms failed to exceed significance threshold.
The Effect of Absolute Value vs. Relative Value of Reward on Associative Memory
Advisors: Dasa Zeithamova-Demircan, PhD and Lea Frank, MS
People tend to remember information associated with high reward values better than low reward values. However, what is perceived as “high” reward may be relative to other potential rewards. Here, we hypothesized that the memory advantage for a given reward value (e.g., penny over no reward) diminishes as higher possible rewards are offered. In the task, participants studied pairs of common objects, preceded by a cue indicating how much money they could earn (no reward, penny, dime, or dollar) for remembering the pair at a later test. Study block 1 included only no reward and penny cues, dime cues were added in block 2, and dollar cues were added in block 3. At test, participants saw one object from each pair and named the object that was paired with it at study. Contrary to our hypothesis, reward effects on memory were independent of other offered rewards. Together, these findings indicate that the absolute values of reward, rather than the relative values, dictate the effect of reward on memory performance.
Undergraduate Honors Projects – 2017-2018
Jared F. Acosta-King
Neural Mechanisms for Stereo Olfaction in Mice
Advisor: Matt Smear, PhD
The abilities to seek out and spatially locate sources of food, find a mate, and identify potential predators are essential skills for survival. Many of the senses that are utilized by mammals for such tasks use stereo as a means for localization, such as stereo vision for perception of depth, or stereo audition for perception of azimuth and elevation. For many mammals, olfaction is necessary for foraging and threat detection, and although they can locate odor sources based on stereo, how olfactory systems process and compare stereo input remains enigmatic. We hypothesize that animals compare timing across two sides to judge azimuth, similarly to audition. Due to the difficulty of stimulus control, to test this hypothesis using odors is infeasible. To circumvent this difficulty, we use transgenic mice in which olfactory sensory neurons (OSNs) express channelrhodopsin, so that we can initiate olfactory input with light. Using a simple go no-go behavioral assay, we will examine the ability of mice to sense timing differences between the stimuli delivered to OSNs on both sides of the olfactory bulb. These experiments will illuminate the neural code with which the early olfactory system represents stereo differences. Further, this project is a first step toward our longer-term goal: to understand the brain circuits that perform stereo computations.
The Influence of Women’s Self-Perceptions of Ability and Effort Expenditure on Science, Technology, Engineering, and Math Field Persistence
Advisors: Sara D. Hodges, PhD and Kathryn Denning, MS
Women in the United States consistently drop out of Science, Technology, Engineering, and Math (STEM) fields at various points along the career pathway. While discrimination is a factor, women’s perceptions of themselves and their field may influence the decision to leave STEM at the undergraduate level. The current study paired 121 male and female STEM undergraduates interested in pursuing advanced degrees with graduate students in their field for a discussion about graduate school preparedness. Afterward, we used questionnaires to measure the undergraduates’ self-perceived levels of natural ability, effort exertion relative to others in their field, domain motivation, beliefs about the relationship between effort and ability, and beliefs about the importance of natural ability to success in their field. We predicted that these variables would influence likelihood of persistence in STEM fields and found that domain motivation and self-reported ability were significant predictors. However, contrary to our prediction, self-reported ability had a negative relation with likelihood of persistence. Interestingly, we found no gender differences for likelihood of persistence, indicating that women may be more likely to remain in STEM fields than previously thought. These findings could represent positive news for the representation of women in STEM and suggest that motivational factors and self-perceptions of ability should be examined in future research.
The Origins of Empathy During Infancy: Links to Theory of Mind and Empathic Prosocial Behavior at Age 5
Advisors: Jennifer Ablow, PhD and Jeffrey Measelle, PhD
Researchers examining the developmental origins of empathy report that infants as young as 17 months show early evidence of empathic behavior in the form of concern for others, positive affect, and emotional distress (Zahn-Waxler, & Robinson, 2005). In turn, a vast amount of research demonstrates the long-term outcomes of empathic children, such as prosocial development, high self-esteem, few externalizing problems and a positive disposition (Eisenberg, Fabes & Spinard, 2015). In addition, early empathic tendencies predict earlier onset of Theory of Mind (ToM), which is the ability to attribute beliefs and desires to self and others (Laranjo et al., 2010). Evidence suggests that ToM develops within the context of the parenting relationship during infancy (Laranjo et al., 2010), through parenting mechanisms such as Maternal Mind-mindedness, which is the ability to treat children as their own entities’ with their own minds through the usage of appropriate mind related language. Though there is vast literature on the outcomes of early empathy, there is little research on the development of empathy prior to 17 months. Given links between Maternal Mind-mindedness in infancy and early onset of ToM, and links between early indices of empathy and ToM, this study examined Maternal Mind Mindedness at 5 months and its associations with infant empathy at 17 months. These, in turn, were used to predict children’s ToM and empathic prosocial behaviors at 5 years. Although our results did not find an association between Maternal Mind-Mindedness and ToM, we did find a significant longitudinal associations between Maternal Mind-mindedness and Global Empathy, Attachment Security, Empathic Prosocial behaviors.
Is Efficient Coding a Cognitive Primitive of Working-Memory Capacity?
Advisors: Atsushi Kikumoto, MS and Ulrich Mayr, PhD
Working memory capacity (WMC) is usually regarded as a cognitive primitive that explains intelligent behavior, including the ability to recognize and utilize patterns in the environment. The efficient-coding hypothesis (Botvinick, Weinstein, Sloway, & Brato, 2015) posits that our neural system has evolved to code sensory information by utilizing redundancies and patterns in the sensory input in order to minimize storage demands. This suggests that variability in working memory capacity may be a consequence of variability in “intelligent” utilization of environmental structure. In other words, efficient coding may be the cognitive primitive that is responsible for variability in working-memory capacity. As an initial test of this hypothesis, we assessed in a group of subjects (a) working-memory capacity through a simple change-detection task, (b) the ability to detect patterns of varying structural complexity and (c) as a control task, the ability to make simple perceptual discriminations of varying difficulty. On the basis of the efficient-coding hypothesis we predicted that pattern-detection ability would be more highly correlated with working-memory capacity than perceptual-discrimination ability.
Alcohol Use and Mental Health across the Transition into College: A Longitudinal Perspective
Advisors: Nicholas B. Allen, PhD and Melissa Latham, MS
On college campuses, problematic drinking behavior has become normalized. Students drink heavily, vomit, attend class hungover, and they often discuss this behavior with levity. While several studies show that alcohol consumption increases significantly during the first year of college, few shed light on contributing influences (Capone, Wood, Borsari, & Laird, 2007; Fromme, Corbin, & Kruse, 2008; Sher & Rutledge, 2007; White et al., 2006; Read, Wood, & Capone., 2005). This study examined patterns of change in alcohol use across the transition into college and asked whether pre-college depression or anxiety moderate these patterns. Data was collected through AlcoholEdu, a substance abuse program required of all incoming students of the 2016-17 academic year (n = 4,681). The longitudinal design included two surveys. Students completed the first survey prior to the start of fall quarter and the second approximately 1 to 4 months into their first year. Our first two hypotheses were supported, while our second two were not. Alcohol problems significantly increased across the transition into college, with male students experiencing greater increases in first-term alcohol problems than female students. However, pre-college depression did not predict greater increases in first-term alcohol problems, and neither did pre-college anxiety. Results suggest that the transition into college negatively impacts drinking behavior, specifically for male students. These findings may also point to future research regarding collegiate mental health, Greek involvement, and drinking motives.
Enhancing Low Frequency Rhythms in the Motor Cortex of Humans.
Advisors: Pascale Voelker, PhD and Mike Posner, PhD
In previous work it was found that 2-4 weeks training of mindfulness meditation increased white matter connectivity in pathways surrounding the anterior cingulate. It was hypothesized that this change might be mediated by theta rhythms (4-8Hz) found to increase after meditation training (Posner et al,2014). Theta rhythms are associated with internalized attention and positive emotional states. In our laboratory, mice receiving laser stimulation of the anterior cingulate cortex (ACC) at theta frequency (4-8 Hz) showed evidence of improved connectivity as measured by g-ratio (axon diameter/axon diameter + myelin). To extend these results to humans, we stimulated the ACC by applying electrical stimulation at theta frequency (6Hz) to a set of scalp electrodes overlying that area. Following stimulation, we found enhanced low frequency power in ACC sites compared to baseline, and this power increased when a task known to stimulate the ACC was performed. Our current work tests whether this method could be applied to other brain areas. We chose a task activating the hand region of the primary motor cortex and electrodes stimulating the motor area. We tested 12 undergraduates using a generic set of electrodes known to stimulate the motor area, and compared this with electrodes selected for each person based on structural brain images. We found an increase in baseline theta activity over the course of the experiment. We saw enhanced theta activity while performing the task and with electrical stimulation while performing the task. There was no significant change in theta activity with electrical stimulation alone and the configuration of electrodes did not seem to show substantial differences. We found that baseline theta levels could be enhanced in the motor system by an appropriate task.
Title: Dissociative Traits vs. Symptoms: Associations with Parasympathetic Responding During Trauma Recollection
Advisors: Jeffrey Measelle, PhD; Jennifer Ablow, PhD; and Jenn Lewis, MS
Abstract: Trauma experiences are known to be associated with higher levels of dissociation when triggered by recollection. Dissociation can be measured on a continuum, as both a trait and clinical symptoms of psychopathology, although little research has explored physiology relating to both sides of this continuum. The Polyvagal Theory suggests that dissociation, a form of immobilization, can be a defense mechanism to cope with an inescapable fear or danger. In keeping with this, research has shown through investigations of psychophysiology that dissociation activates the parasympathetic nervous system (PNS), or the branch of the autonomic nervous system that attempts to regulates stress. This study recorded continuously measured respiratory sinus arrhythmia (RSA), an index of PNS functioning, in 64 primiparous women discussing trauma during the Adult Attachment Interview (AAI). There were significant physiological differences between talking baseline and the trauma questions as demonstrated by increased RSA during personal trauma recall. When regarding trait versus symptomatic dissociation, symptomatic showed a significant association with sympathetic nervous system activity, showing decreased RSA. These results suggest that in those with symptoms of dissociation, there may be a period of arousal preceding the increase in RSA that has been found to be linked to dissociation.
Puberty and Valence of Word Use in a Novel Self-description Task in Adolescent Girls
Advisors: Jennifer Pfeifer, PhD and Monika Lind, MS
Frequently defined by the onset of puberty, adolescence is a time of significant development of the self and is often associated with the variability of experienced affect. Past research has examined the neural bases of self-concept and self-knowledge, as well as used the Ecological Momentary Assessment to measure affect in adolescences. However, few studies have considered if pubertal development is associated with valence of expressed language when describing the self. A sample of 116 female participants, ages 10.06 to 13.17 years old, completed a video task and answered the Pubertal Development Scale questionnaire during Session 2 of the Transition in Adolescent Girls (TAG) study. The video task, This Is Me, allowed participants to introduce and describe themselves for sixty seconds in front of a computer web-camera. The current study utilized the data from TAG and investigated whether or not two associations existed: between puberty and positive affect, and between puberty and negative affect. The results revealed non-significant associations. For future studies involving data from This Is Me, researchers can take two approaches: 1) examine within-subject changes in valence of expressed language and 2) measure affect using a facial recognition program, instead of sentiment analysis.
The Effect of Sleep on False Memories
Advisors: Nash Unsworth, PhD and Melynda Casement, PhD
A false memory is recalling incorrect information, or recalling an event that did not happen. Everyone is susceptible to false memories. There is no known cure or defense, and relatively little is known about how they occur. Though there is relatively little known, much research shows sleep, consolidation specifically, is crucial to solidifying memories (Payne, Chambers, and Kensinger, 2012). Consolidation is a process where new, labile memories are integrated into the vast network of pre-existing long-term memories. A key component of this process is the active re-processing of these memories, because this is the version of the memory that will be recalled (Diekelmann and Born, 2010). Memory is malleable, so it is important to understand how it is affected. This study seeks to find a connection between the number of hours of sleep a subject gets and how many times they experience a false memory. Using the Deese-Roediger-McDermott paradigm, subjects were asked to memorize four lists of 10 words all related to a single theme word. Then, subjects were asked to recall words from each list. A false memory was counted each time a subject mistakenly reported the theme word. We hypothesized that subjects sleeping a “normal” eight hours per night would experience fewer false memories compared to subjects who slept greater than 10 or less than five hours per night. We seek to answer the question: is someone more or less susceptible to false memories based on the number of hours they sleep?
The Effectiveness of Value Based Self-Affirmations via Text Messaging on Feelings About Healthy Eating
Advisor: Elliot Berkman, PhD
More than a third of adults and 17% of youth between 2011-2014 were obese, and obesity has seen a steady increase from 1999 to 2014 (Ogden et al., 2015). Given that public health messaging is prevalent and yet obesity continues to rise, reducing obesity at the population level apparently requires more than simply increasing the availability of healthy eating information. It is possible that motivational messages (as opposed to informational ones) will be effective in changing diets. This study measures the effectiveness of value-based self-affirmations on feelings about healthy eating (termed healthy eating affect). Adult overweight and obese participants (N = 91, ages 34-46) were randomly assigned to receive either self-generated text-messages grounded in personal core values related to healthy eating or generic healthy eating information provided by government funded. We tested the hypothesis that those who received value based self-affirmations via text-messaging would show significantly greater positive affect towards healthy eating than those who received generic or otherwise less personally relevant text-messages (e.g., messages only weakly connected with self-affirmations). Participants underwent a standard self-affirmation induction (value ranking and writing exercise) then self-generated messages describing how healthy eating was connected to their personal values. All messages were qualified by blind coders from high to low on how well they represented the participants’ core values. A factorial ANOVA will test the effect of self-affirmation quality on healthy eating affect. Implications of these data on healthy eating affect are to be determined upon the completion of this study.
Nathaniel Lee Sichter
Nutrition and Anemia in Lao Children: Determining Contextual Correlates
Advisors: Jeffrey Measelle, PhD and Dorianne Wright, MS
The present study investigated the associations among diet, hemoglobin concentration, and the presence of anemia in young Lao children, hypothesizing that children’s dietary profile would be correlated with hemoglobin concentration, that children with poorer dietary profile would be more likely to have anemia, and that social factors such as ethnicity might moderate these association. Data were collected in 2014 from 572 children under five years of age in 90 villages across three districts in northern Laos to measure a wide range of health indicators, including infant health status, families’ nutritional practices, composition of food basket, and issues of food security. Due to missing data, the sample was reduced to 534 in models predicting dietary score and 508 for hemoglobin concentration/anemia. Our cutoff for determining anemia was hemoglobin concentrations under 11g/dL. When holding all other variables constant, no association between dietary score and hemoglobin concentration was found ( F(1, 498) = 0.001, p = 0.972). However, significant main effects of child age (F(1, 498) = 14.672, p <0.001), breastfeeding (F(1, 498) = 14.27, p <0.001), and ethnicity (F(1, 498) = 4.92, p = 0.03, F(1, 498) = 12.31, p <0.001) predicted hemoglobin concentrations. When predictors of diet were examined, only child age was a significant predictor (F(1, 521) = 6.35, p = 0.012). A logistic regression model predicting anemia found that children’s age and breastfeeding were the only significant predictors. Specifically, the odds of developing anemia were 0.972 times less for older children (95% CI[0.956, 0.989]) and 0.518 less for children whose mothers reported that they were still breastfeeding their child (95% CI[0.315, 0.851]). Ethnicity did not moderate any of the associations.
Contrary to prediction, children’s diet did not predict hemoglobin concentrations or the likelihood of clinically significant anemia. However, older children had higher hemoglobin concentrations, better diets, and a decreased likelihood of developing anemia. Importantly, breastfeeding was also found to predict higher hemoglobin concentrations and a decreased likelihood of anemia, pointing to the protective effects of breastfeeding in a nutritionally challenged region of the world.
The Interaction of Stress and Sleep in Reward Motivation
Advisor: Melynda Casement, PhD
Existing literature indicates that stress and sleep contribute to the onset and severity of depression, but there is limited research on the interaction between stress and sleep in their relationship to depression and depressive symptoms. The present study evaluates a model in which stress and sleep interactively contribute to reward motivation in depression. Participants were 51 young women (M= 19.7, SD= 0.47) from the Pittsburgh Girls Study (PGS; Keenan et al., 2010). Perceived stress and sleep duration were measured daily for a week prior to a behavioral measure of reward motivation. Perceived stress and depressive symptom severity were assessed via self-report, and sleep was assessed using self-report and behavior. I hypothesized that higher perceived stress and lower sleep duration would both predict lower reward motivation (i.e., fewer decisions to perform difficult tasks when the probability of success was 50%). Additionally, I expected an interaction between stress and sleep such that as sleep duration decreased, the effect of stress on reward motivation would increase. ANOVA results indicated that neither sleep duration nor perceived stress were associated with reward decisions. In addition, neither sleep, nor stress, nor reward motivation were associated with depressive symptom severity. The absence of significant bivariate relationships between sleep and depression, stress and depression, and depression and reward motivation is surprising in light of the reliability of these associations in prior research. The failure to replicate prior studies may be related to the demographic characteristics of the sample, which is predominantly African American women with low socioeconomic status, or the presence of research fatigue after nine waves of PGS data collection and a week of daily measures of stress and sleep. Future research may need to devise methods of data collection that promote the integrity of participants’ responses in high-demand studies.
Associations in Adverse Childhood Experiences and Parasympathetic Response during Social Engagement in At-Risk Children
Advisors: Emma Lyons, MA; Elizabeth Skowron, PhD; and Caitlin Fausey, PhD
The development of physiological self-regulatory abilities is crucial in the early years of human life (Porges, 2011) and is negatively affected by experiences of childhood adversity (McLaughlin et al., 2015). The parasympathetic nervous system (PNS), a branch of the autonomic nervous system, is extremely important in regulating physiology when a person is under stress and at rest. The present study examined the development of the PNS and how experiences of adversity during childhood development affect the PNS. Specifically, the study examined the relationships between adverse childhood experiences (ACEs) and the parasympathetic stress response in children during a social engagement task. Participants (N = 97) were 3 to 7-year-old children whose mothers were involved in DHS. Respiratory sinus arrhythmia (RSA) was measured while children were at rest and during a social engagement task with an unfamiliar adult. Change scores were calculated to demonstrate task-level parasympathetic response. Adverse Childhood Experience Scale (ACES) scores were used as a measure of how much adversity the child had experienced. RSA change scores and ACES were compared utilizing regression analysis while controlling for age, and no significant relationship was found between the variables. Future research with a larger sample size in conjunction with measuring and controlling for other potentially important variables is suggested.
Thin-Slice Socioeconomic Status: Comparing Thin-Slice and Longer Judgements of SES and the Cues that Inform Them
Advisors: Sanjay Srivastava, PhD and Bradley Hughes, MS
Thin-slice perceptions, those made of others after a brief observation, have been shown to be similar in accuracy to those made after longer observations across many individual difference measures. Recent work has shown thin-slice observations of socioeconomic status (SES) may also be accurate. The purpose of this research was to test if thin-slice judgements of SES are as accurate as those made after longer observations and to examine the expression and utilization of a number of hypothesized cues of SES. We compared 60-second thin-slice ratings of SES to those made after observing the target for 20-minutes. Further, we employed a Brunswik lens model to examine whether perceivers utilized expressed cues. One-hundred and forty-two targets were rated by 115 participants. Inconsistent with previous research, neither thin-slice ratings of socioeconomic status nor ratings made after a 20-minute observation were accurate predictors of self-reported SES. Additionally, there was no relationship between thin-slice ratings of SES and those made after longer observations. Despite the lack of accuracy in ratings of SES, perceivers appear to rely on similar ques to make their ratings.
This study is preregistered through the Open Science Framework.
The Effect of Abstract Chunk Patterns on Sequential Performance
Advisors: Ulrich Mayr and Melissa Moss
Complex sequential performance is typically thought to be based on hierarchically organized control structures, which break larger sequences into small sub-sequences (“chunks”). However, such models of sequential behavior do not specify the nature of chunks and how different chunks within a sequence relate to each other. The efficient coding hypothesis (Botvinick, Weinstein, Solway, Andrew, & Barto, 2015) suggests that our neural system optimizes information storage by exploiting structure in the to-be-coded information. Applied to the problem of serial-order control, this general hypothesis suggests that different chunks are not coded in terms of arbitrary labels, but instead in relation to each other. Specifically, this implies that sequences that consist of “relatable” chunks can be coded in a more efficient manner than less-relatable chunks. To test this novel prediction, we assessed the effect of ‘matching’ chunk patterns on performance in a complex sequencing task. Participants completed a spatial rules task (see Mayr, 2002), in which they were asked to execute a number of complex sequences with either similar, or dissimilar, abstract chunk patterns (e.g., an ABA pattern for both chunks 1 and 2 vs. an ABA pattern for chunk 1 and an ABB pattern for chunk 2). Within-subjects analyses revealed better performance (shorter response times) in sequences containing matching chunk patterns than in sequences containing non-matching patterns. Additionally, this effect was strongest at chunk transitions. These findings indicate that chunks within complex sequential representations are coded in relation to each other, as the efficient-coding hypothesis would suggest.