University of Wisconsin–Madison

PREP Journal

  • 2016

    Barber, Gregory

    Morehouse College

    The Role of Socialization in Recalling Death Experiences and its Relation to Coping and Bereavement

    Researchers have investigated socialization extensively through the lens of gender, race and culture. There is, however, a gap of research exploring how children are socialized to understand death. Death socialization is important because the death of a loved one is still one of the most traumatic experiences an individual can experience (Dowrenwend & Dowrenwend, 1974). This study’s purpose is to analyze the role of children’s socialization of death and its influence on the coping and bereavement process. Using a survey, we analyzed 319 participants using Amazon MTurk and asked them to recall their childhood death socialization and death experiences of a close friend, family member, or pet. A structural equation model suggested socialization and gender as predictors of how people cope with death experiences. Future researchers should look at the role of pets in socialization, among other factors that facilitate the coping and bereavement process.

    This research was performed in the laboratory of Professor Karl Rosengren


    Burris, Imani

    University of California – Santa Barbara

    Comparing the Effects of Prejudice Interventions in Reducing Attitude Resistance

    Prejudiced attitudes are tied to individuals’ social identities, which lead to the favoring of their in-group over out-groups. Several prejudice interventions have yet to overcome attitude resistance outside of laboratory settings, because such interventions rely on systematic processing. The present study sought to overcome attitude resistance and reduce prejudice by comparing the effects of entertainment media, which relies on heuristic processing, with those of other established prejudice interventions. In this field experiment, 105 participants were recruited throughout the U.S. and randomly assigned to one of four conditions: entertaining narrative, imagined contact, counter-stereotypic imaging, or control. After completing a short activity, participants in the interventions completed resistance and prejudice measures, while those in the control condition completed the prejudice measures only. Contrary to our hypothesis, preliminary findings reveal that the entertaining narrative was not the most effective in overcoming resistance and reducing prejudice. Implications and future directions are discussed.

    This research was performed in the laboratory of Professor Markus Brauer


    Cui, Lucy

    University of California – Los Angeles

    Long-Term Training on the Approximate Number System: A Psychophysical Approach

    Humans have a non-symbolic number sense that complements symbolic number sense training in formal education. Many researchers have asked whether this non-symbolic number sense, also known as approximate number system (ANS), relates to and affects mathematics ability. However, all ANS studies present stimuli centrally and investigate effects between some ANS task and some mathematics task. This study investigates psychophysical questions related to ANS training:  1) Is ANS trainable?, and 2)  Does ANS training transfer to different quadrants,  to a lower level task: enumeration,  to a higher level task: ratio comparison, and to arithmetic ability?, and 3) Are improvements explained by attentional learning? Participants took part in long term training (28 sessions) on the standard ANS task parafoveally. Participants’ ANS acuity (did/not) improve throughout training (and/but not) between pretest and posttest. A psychophysical approach can guide parameters of ANS interventions for those with dyscalculia.

    This research was performed in the laboratory of Professor Shawn Green


    Husby, Natalia

    University of North Carolina – Greensboro

    Examining the Long-term Effects of Infant Rearing Experiences on Delay of Gratification Tasks by Adult Rhesus Macaques (Macaca mulatta)

    Delay of gratification has been measured across various species (primates, rodents, birds). For Rhesus macaques, impulsive-aggressive behaviors are more prominent in animals that had disrupted social relationships during infancy (i.e., nursery-rearing). No previous study has examined the impact of differential infant rearing experiences on impulsivity in terms of cognitive control in rhesus monkeys. Further, little is known about their performance in delay maintenance tasks. Twelve male rhesus macaques (6 nursery-reared; 6 mother-reared) participated in a delay of gratification task in order to test the hypothesis that nursery-reared monkeys would show less ability to delay gratification compared to mother-reared counterparts. Five phases of delay maintenance tasks were conducted. Nursery-reared monkeys delayed longer than mother-reared monkeys, but only in Phase 1, (p = .03). The present study demonstrates that rearing experience may impact cognitive control, but more studies are needed to confirm this hypothesis.

    This research was performed in the laboratory of Professor Allyson Bennett


    Merritt, Haily

    Indiana University – Bloomington

    The Effect of Explicit Knowledge in Problem Solving and Learning

    Previous research has indicated that non-verbalized knowledge is not thoroughly evaluated, allowing room for inconsistencies and gaps. When people do verbalize what they know via explanation, they are more likely to notice the subtler—but also more generalizable—features of a problem. The present study investigated the role of explicit knowledge in problem solving and learning. We utilized three versions of Bongard problems: a Source problem, where a feature was introduced; a Transfer problem, where the learned feature was useful in solving the problem; and an Irrelevant problem, where the feature was salient but not relevant to the solution. We hypothesized that participants would solve Bongard problems more accurately when they verbalize their solutions. Our data suggest that, while there was no effect on Transfer problems, participants who verbalized their solution where better able to inhibit the learned irrelevant feature in Irrelevant problems.

    This research was performed in the laboratory of Professor Gary Lupyan



    Vasavan, Aditya

    St. Olaf College – Northfield

    Scientific Thinking and Data Interpretation

    Data interpretation is an important concept to teach children from a young age, as it is imperative to being able to properly understand academic results and apply them to the real world. A number of other general cognitive abilities have been shown to correlate with mathematical analyses, which are, in turn, related to data interpretation, but scientific thinking seems to be the most likely to have an effect on how people interpret data. Ten adult undergraduate students had their data interpretation skills, scientific thinking, inhibition, arithmetic ability, proportional reasoning, general intelligence, working memory, and reading comprehension assessed independently. Scientific thinking was not associated with data interpretation and none of the other general cognitive abilities were correlated with interpretation of data. Future studies will include a more representative sample size, a more comprehensive measure of scientific thinking, and a multiple regression analysis of the relation between scientific thinking and data interpretation.

    This research was performed in the laboratory of Professor Martha Alibali





    Zayas Alom, Gabriela

    University of Puerto Rico – Rio Piedras

    Learning of Gender versus Number Regularities by Native Speakers of English

    Previous research has shown that people have trouble learning dependencies that their own language does not have. However, this research wasn’t well controlled for properties of the languages and manner of instruction. Using an artificial language paradigm, we investigated whether native English speakers would be better at learning gender or number dependencies. Participants learned an artificial language accompanied by a visual world made up of monsters. We assessed learning of gender and number dependencies by an error monitoring test, which contained gender and number agreement error sentences. Results showed that participants were better at learning gender rather than number dependencies, which was surprising given that English does have number but does not have gender. Further, we explored the role of experience in learning a new language through a language background questionnaire. We found that experience with another language was a significant predictor of how well participants learned these dependencies.

    This research was performed in the laboratory of Professor Maryellen MacDonald

  • 2015



    Baird, Nicholas

    University of Minnesota – Twin Cities

    You Test What You Can Name: The Role of Dimensional Nameability in Testing Hypotheses During Category Learning

    Historically, language has had a tremendous amount of theoretical and empirical speculation about its role in thought. In the cognitive sciences, the mainstream view is that language is separated from thought. Recently, language has seen a range of assertions that demonstrate its role in cognition. These claims illustrate the importance of language in determining cognitive outcomes. In particular, language’s role in category learning has come under investigation. In tandem with literature on active and passive hypothesis testing in category learning, we investigated how language impacts learning performance via dimensional nameability (i.e., how likely a set of words is available that succinctly highlight what is important). In a series of studies, dimensional nameability predicted performance on learning physical Bongard problems. Dimensional nameability did not improve or hinder performance in either active or passive learning. Limitations on the design of the categorization task may have reduced a main effect.

    This research was performed in the laboratory of Professor Gary Lupyan


    Estep, Tiffany

    Berea College

    Effects of Collaboration on Learning How to Solve Equivalence Problems

    We investigated how collaboration influences learning in second and third grade students solving equivalence problems. Children worked in three types of pairs to solve problems during the collaboration session. Some pairs consisted of two children who demonstrated prior knowledge of equivalence, some pairs consisted of two children who did not demonstrate prior knowledge, and other pairs consisted of one child who did and one child who did not. We hypothesized that strategy disagreement between children would lead to higher scores at posttest. Results indicated that disagreement does not predict learning. This suggests that there may be other pressing factors that contribute to children’s learning, such as noticing problem structure.

    This research was performed in the laboratory of Professor Martha Alibali


    Harper, Khatiti

    Kenyon College

    Statistical Learning of Paired Associates in Children

    Two studies investigated whether children could learn patterns in stories. In both experiments, children listened to a story and completed a pair-matching task on an iPad. We presented children with pairs listed in random order to explore pattern learning. In the first study, this task asked children to identify predictive pairs (pairs with 100% transitional probability), and the results showed that children were able to learn the pattern. In the second experiment, we designed a more difficult test of learning by asking about both the predictive and non-predictive pairs (pairs with 30% transitional probability on average). In the second experiment, children were unable to learn the predictive pairs. Further research should examine why there was this shift in learning and define an efficient testing phase before continuing to manipulate attention.

    This research was performed in the laboratory of Professor Jenny Saffran


    Menendez, David

    University of Wisconsin – Madison

    Mexican and U.S. Children’s Understanding of Death: A Cultural Perspective

    Past research examining children’s understanding of death has focused mainly on finding a universal developmental trend. We investigated the development of a biological concept of death in context by looking at how culture, parental beliefs, and past experience with death might reveal earlier competencies in children’s understanding of death. We compared data from 62 children from Mexico (ages 4-6) and 102 children from the U.S. (Rosengren,  Miller, Gutiérrez, Chow, Schein, and Anderson, 2014). We found that children in the U.S. had a more biological understanding of death than children in Mexico. We suggest that the way in which children are socialized into cultural practices surrounding death might impact the way they conceptualize death.

    This research was performed in the laboratory of Professor Karl Rosengren


    Ojeda, Alyssa

    Texas State – San Marcos

    Interactions Between CRF and Noradrenergic Alpha-1 Receptors in the Rat Prefrontal Cortex

    The prefrontal cortex (PFC) modulates higher cognitive processes including working memory.  Recent studies in our laboratory indicate that the stress-related neuropeptide, corticotropin-releasing factor (CRF), acts within the PFC to impair working memory, similarly to noradrenergic alpha-1 receptor activity.  Therefore, we investigated whether the CRF and noradrenergic systems interact in the PFC. Fluorescent double-label immunohistochemistry was used to detect alpha-1 receptors and CRF in the rat PFC. Over 100 CRF- and alpha-1 receptor-immunoreactive cells within the PFC were counted.  Our results indicate that CRF and alpha-1 noradrenergic receptors are highly co-localized in the PFC, which has implications for drug development in the treatment of prefrontal dysfunction.

    This research was performed in the laboratory of Professor Craig Berridge



    Romulus, Darwin

    Brooklyn College

    Let’s Play Pong: Errors in 3D Target Estimation Depend on Eccentricity

    When directly observing moving objects, humans often surprisingly confuse motion in depth reporting approaching objects as receding and vice versa. However, lateral motion is accurately perceived. As objects move in depth, their corresponding motion on the retinas is small compared to retinal motions corresponding to laterally moving objects. We hypothesize that small motions impose greater uncertainty in visual processing giving rise to greater confusion in depth. This hypothesis predicts that the nature of confusion will change in the periphery where laterally moving objects have smaller corresponding motion on the retinas relative to objects moving in depth. Using a virtual reality environment, we measured participants’ accuracy in estimating the direction of objects moving at fixation and in the periphery. When fixating objects, participants exhibit significantly more misreports of motion in depth than of lateral motion, thus replicating previous findings. We find a significant increase in misreports of lateral motion for estimation of the direction of objects moving in the periphery. No impact is observed in estimation of motion in depth when compared to performance at fixation. These results support our hypothesis and suggest that the nature of retinal motion impacts the reliability of the information used by visual processes responsible for 3D object motion direction estimation.

    This research was performed in the laboratory of Professor Bas Rokers





    Tran, Selena

    University of Massachusetts – Lowell

    Working Memory Precision: Slots versus Resources

    Two models aim to explain the capacity limits of visual working memory (VWM): the slots model and the distributed resources model (DRM). The slots model states each visual item is held in an individual slot, where the capacity limit is up to four objects regardless of the number of features. The DRM states that memory resources are allocated among the various items kept in VWM, where the precision of memory is dependent on the number of features regardless of the number of objects. To test the effects of varying feature load independently of object load, participants completed a memory task involving varying featural loads of color and direction. We found increasing featural load of direction resulted in a drop off of precision, while increasing featural load of color did not result in a drop off of precision. This suggests that memory mechanisms for direction operate under the control of the DRM, while color operates under the control of the slots model.

    This research was performed in the laboratory of Professor Brad Postle

  • 2014
    Bauer, Phoebe Reed College

    Top-Down Control of the Phase of Alpha-Band Oscillations as a Mechanism of Temporal Attention

    Much of the research on temporal expectation has focused on stimulus-driven modulation of

    perception, rather than top-down control of temporal attention. Here we examined the effects of a cue containing information as to when a stimulus would appear on behavioral performance and on the progress of alpha-oscillations (9-13 Hz) in visual cortex. We collected electroencephalography (EEG) recordings while participants completed a target discrimination task in which some targets appeared at a predictively-cued latency, while others appeared at an unpredictable latency. We found that top-down temporal attention improved perceptual processing, demonstrated by an increase in accuracy following a predictive cue at the short delay. The concurrent electrophysiological data revealed accompanying modulation of the phase of alpha such that phase differences were seen prior to target onset between predictively and unpredictively cued trials at both latencies. Furthermore, the phase during these attended windows was biased towards that optimal for stimulus detection for each individual participant.  These data demonstrate a functional consequence of the phase of alpha, suggesting that these oscillations are not merely a noisy byproduct of an idling system, but rather a feature under top-down control that may serve as a mechanism for directed attention.

    This research was performed in the laboratory of Professor Brad Postle


    Finney, Rebecca Gordon College

    The Impact of Task Difficulty and Individual Differences on Learning

    Learning is optimized when the difficulty level of a task is “just hard enough” (Lui, 2012). However, it is unclear whether participants learn best when they are presented with a task in which the difficulty level adaptively increases/decreases in response to the participants’ performance (i.e., the staircase method), or when difficult and easy trials are randomly intermixed (i.e., the constants method). As such, the purpose of the current study was to examine whether perceptual learning differs depending on whether participants receive training with a staircase, or a constants, method. Thirty-two participants were placed into either a staircase or a constants training group, and completed a perceptual learning task. All participants began with a constants pre-training block, after which they completed 3 training blocks using either the staircase or the constants method. All participants then completed a constants post-test. A variety of individual difference factors were also examined to determine whether they could predict the amount of learning that resulted from both staircase and constants training. While both groups of participants showed significant improvements after training, there was no influence of task on learning performance. Additionally, there were no significant correlations between individual difference factors and pre-post scores for either group, although many of the relationships approached significance. This study demonstrates that, regardless of their subjective differences, training with the staircase and constants methods lead to similar improvements in perceptual learning. However, further research is needed to better understand the influence of individual differences on perceptual learning.

    This research was performed in the laboratory of Professor C. Shawn Green


    Grahn, Chelsea Ripon College

    Developing a Flicker Paradigm to Assess Visual Working Memory in Early Childhood

    The current study focuses on the development of visual working memory in early childhood. We tested predictions of a dynamic neural field model. This model suggests that adults are more likely to correctly identify the correct stimulus in a change detection task involving colors when high-similarity colors are presented, as compared to when low-similarity colors are presented. An adaptation of this model with parameters scaled to simulate children’s performance suggests that the opposite phenomenon should occur early in development, with children being more accurate in their responses when low-similarity colors are presented. In this study, we developed a new “flicker” paradigm to test children’s ability to detect changes in color on high- versus low-similarity trials. Twenty-seven 3-year-old and 16 5-year-old children participated in this study, in addition to 10 adults. Results indicate that in the current task, all age groups showed the same general pattern of better performance on high-similarity trials, contrary to the predicted developmental difference.  We consider how these results can be used to understand how memory may influence behavior differently depending on the structure of the task.

    This research was performed in the laboratory of Professor Vanessa Simmering


    McClarin, Jalina Carlow University

    Individual Differences in Learning Relational Categories: A Look at the Importance of Labeling in Same/Different Tasks

    Relational categories, or categories of entities that share a common abstract relation but not any perceptual commonalities, are thought to be critical for abstract thought. They are generally difficult for children and nonhuman animals to learn. Although most adults easily learn relational categories, in experiments exploring a particular type of relational category—the same/different relation—a minority of humans and all non-human animals (specifically pigeons) categorize same/different arrays that have levels of variance based on how varied they are rather than based on the discrete categories of “same” and “different.” Because previous research suggests that labels aid in categorization (specifically in relational categories), we ask whether ability to label relational categories in general predicted individual differences in categorizing instances of same and different. We conducted a correlational study to examine the relationship between ability to categorize and name same/different arrays, and ability to complete and name relational analogies. Results indicate a trending, though not significant, relationship between relational analogy ability and same/different categorization ability, such that those who can name relational analogies are slightly better at categorizing and naming same/different arrays. Future research will be needed to better understand the nature of this relationship.

    This research was performed in the laboratory of Professor Gary Lupyan


    McLamore, Quinnehtukqut Bard College

    Testosterone May Reveal Individual Differences in Future Winning Ability in Sexually Naïve Male California Mice

    Recent work in humans has demonstrated that there are individual differences in pleasure-motivated or “hedonic” aggression among men linked to their salivary testosterone response to violent or aggressive stimuli. Corresponding work in the monogamous California mouse (P. californicus) related to the “winner effect” and conditioned place preference (CPP) plasticity in sexually naïve (SN) vs. pair-bonded (PB) males hints that a testosterone-revealed preference of SN male mice to approach male conspecifics may predict higher levels of “hedonic” aggression in these males. We test this hypothesis using repeated “male-female preference tests,” a new paradigm derived from partition tests and CPP studies, followed by an aggressive encounter for 30 SN male P. californicus. Although male-female preference appears to be plastic and subject to test-retest reactivity and related more to the area stimuli inhabit than the animals themselves, and although our aggression index was insufficient to characterize the aggressive behaviors of SN males, our results revealed that males that initially prefer to inhabit the same space as male conspecifics injected with T had a significantly higher chance of winning their aggressive encounter compared to any of the other three groups. This difference in winning ability is not due to the steroid effect of T, as female-preferring males never won an aggressive encounter, even if injected with T. These findings suggest that individual differences in male-female preference may reflect individual differences in aggression circuitry that influence fighting ability.

    This research was performed in the laboratory of Professor Cathy Marler

    Ortiz, Erin Macalester College

    Active Collaborative Learning and Verbal Coordination in Children

    In this paper we investigate the effects of role-relevance and task-relevant communication as mechanisms of collaborative learning in young children. Five dyads of 5-6 year olds and eleven dyads of 7-8 year olds participated in an active category-learning task in order to learn a one dimensional categorization rule. The task required pairs to collaborate in order to learn a rule, where each child controlled either the relevant dimension or irrelevant dimension. Analyses of post-collaboration categorization accuracy and strategies found that role-relevance had an effect on learning. Analyses of verbalizations during the collaborative task revealed that children spontaneously engage in complex verbal coordination, which significantly aids children’s learning.

    This research was performed in the laboratory of Professor Martha Alibali

    Robinson, Haley Lehigh University

    The Effects of State and Trait Brooding on Attentional Biases After an Acute Stressor

    Rumination is an important risk factor for psychopathology, most notably depression. Previous research has linked rumination to cognitive biases for negative information, but the mechanism behind why this occurs is poorly understood. Our current study aims to link two important theories of rumination, the Control Theory account (Watkins, 2008) and the Attentional Scope model (Whitmer & Gotlib, 2012), by showing that both context-specific and negative biases can be induced as a result of brooding, the maladaptive subtype of rumination. Specifically, we aimed to determine whether induced brooding induces biases toward context-specific, goal-related information, which translates into attentional biases toward negative information. We induced brooding by presenting participants with a false intelligence test (Remote Associates Task or RAT) on which they either performed well (control condition) or poorly (experimental condition). We then measured attentional biases using an emotional Stroop Task. We found that the hard RAT induced negative affect and state anxiety, but both versions of the RAT induced state brooding. Neither version of the task induced changes in response times to goal-related or negative information on the Stroop task, but RT to both word types demonstrated trend-level correlations with trait brooding. Finally, trait brooding moderated the relationship between RT to negative and context-specific words such that individuals higher in trait brooding had a strong, positive correlation between reaction times to these two types of information. Our results provide new insights into the relationship of rumination and cognitive processing after a negative event, which could be relevant for understanding development of disorders such as depression.

    This research was performed in the laboratory of Professor Richard Davidson

    Sosa, Rodrigo Vanderbilt University

    Gender Differences in Semantic Representation of Food

    Differences in experience are reflected in semantic structure, which can be measured using multidimensional modeling of participants’ similarity judgment tasks. Is it possible to detect group-level differences and individual differences utilizing the similarity spaces created from multidimensional modeling? Participants were recruited using Mechanical Turk, given a survey, and separated into gender to answer 80 triads in a similarity judgment task. 349 men provided 26695 responses and 331 women provided 25510 responses to create separate similarity spaces for each gender. Differences between the spaces were analyzed by looking at clusters that formed in each space and by identifying words that occupied dramatically different locations in each similarity space. Women answered more consistently than men. The similarity space derived from their answers had more tightly bundled and delineated clusters than the men’s.

    This research was performed in the laboratory of Professor Tim Rogers

    Wang, Michelle Otterbein University

    3D Motion Perception in Virtual Reality Environments

    Accurate motion estimation in our 3D environment is crucial for survival. However, surprising and systematic errors have been reported in the laboratory setting that, if made in the real world, could have disastrous consequences. We hypothesize that visual processing in the real world takes advantage of multiple sources of sensory information, some of which may be degraded or non-existent in traditional psychophysical tasks. Using a carefully controlled virtual reality environment, we manipulated two cues that are important for 3D motion estimation: target contrast and the head motion relative to the surrounding visual environment. Our goal was to identify the association between the degradation of sensory information and participants’ accuracy in 3D motion estimation. We found that performance was negatively impacted by increased sensory uncertainty due to reduced target contrast. We also found evidence that different participants employed different response strategies. These strategies were differentially impacted by the perceptual stability of the surrounding visual environment. Those participants who appeared to adopt a more heuristic-based strategy were less impacted by this cue than participants who attempted to base their responses on all of the available sensory information. These results demonstrate the importance of individual differences in sensitivity to 3D motion information and in the strategies adopted to respond to 3D motion. Moreover, these results extend our understanding of 3D motion perception under sensory uncertainty. Further investigation of the relationship between sensory information acquisition and performance, as well as individual differences in task strategies utilizing that information will provide additional insight into the broader implications of our results.

    This research was performed in the laboratory of Professor Bas Rokers

  • 2013
    Almoite, Maria Minnesota State University at Mankato

    Democratizing small group discussion

    For her PREP project, Maria Almoite had the opportunity to “get in on the ground floor” for a study that investigates how text-chats democratize small group discussions. Maria’s work entailed designing the study, getting IRB (i.e., “human research ethics”) approval, and coding pilot data.
    This research was performed in the laboratory of Professor Morton Ann Gernsbacher
    Hanson, Crystal University of Wisconsin-Madison

    Viewing emotional facial expressions influences sensory judgments

    Functional and evolutionary accounts of emotion suggest a link between emotions and sensory systems. To test this idea, we relied on the assumption that both emotions and conceptual knowledge are, at least in part, embodied. Participants viewed emotional facial expressions prior to making judgments about the visual, auditory, olfactory, and gustatory properties of items. We predicted that fear expressions would facilitate responses for auditory and visual judgments, and expressions of disgust would facilitate responses for olfactory and gustatory judgments. In line with our hypothesis, we found faster responses to visual judgments after viewing fear expressions. However, after viewing expressions of disgust, gustatory judgments were made slower. These results are interpreted under a functional account of emotion where fear enhances perceptual information and disgust inhibits it.
    This research was performed in the laboratory of Professor Paula Niedenthal
    Jensen, Clint University of Kansas

    Abilities in updating intrinsic reference frames in 4-year-olds

    Spatial updating requires the encoding and recall of location relative to one or multiple reference frames. Experiments that disrupt body-centered (egocentric) viewing conditions, through movement of the participant (testing global allocentric reference frames) and/or rotation of a spatial array (testing intrinsic allocentric reference frames) reveal that adults integrate multiple spatial reference frames in an almost seamless manner (Simons & Wang, 1998). However, when adapting those studies to children, 3- to 4-years-olds have difficulty in trials that require updating based on intrinsic reference frames, with marked improvement at 5- 6-years of age (Nardini et al., 2006). The current experiments tested whether 4-year-olds abilities to update spatial location using intrinsic reference frames would be enhanced through a simplified experimental design, and with additional visual support. Experiment 1 allowed participants to view the rotation of the table after turning away from the array for a 10 s interval. Children’s performance in trials that require intrinsic reference frame updating saw significant performance gains. Based on questions as to children’s use of visual-fixation a subsequent experiment was conducted. Experiment 2 again allowed the children to view the rotation of the table, but only after the placement of a “fixation-blind” over the hiding places. Trials requiring the use of intrinsic reference frame updating when both children and the array moved displayed performance comparable to Experiment 1, but regressed in trials where only the array moved. These results suggest developing abilities in 4-year-olds in the use of the intrinsic reference frames as revealed through additive support.
    This research was performed in the laboratory of Professor Vanessa Simmering
    Mahgoub, Lana Grinnell College

    Foreign language discrimination by 3- to 6-year-old monolingual children

    In this study, monolingual English speaking 3-6 year old children were tested in order to better understand how language perception changes with development. Children’s language discrimination abilities in a foreign language categorization task were examined through a presentation of segments of Italian, Spanish and Mandarin. Both Spanish and Italian share the same syllable-based rhythmic class and differ from English which has a rhythmic pattern based on the stress unit. Mandarin, on the other hand, has distinct prosodic and phonological differences from Spanish, Italian, and English. Due to the more pronounced distinction between Mandarin and Spanish than between Spanish and Italian, it was predicted that children would more easily be able to tell Spanish apart from Mandarin than Italian, and that after hearing Mandarin, it would be even harder for them to distinguish between Spanish and Italian than it would be if they were to listen to music beforehand. Music and Mandarin clips therefore served as the manipulated exposure conditions to decide if the introduction of Mandarin, a language that has more distinct phonological cues from Spanish, would make children’s ability to discriminate between Spanish and Italian more difficult even though Spanish and Italian share the same rhythmic class and phonological cues with one another. The results revealed that children do indeed have an easier time distinguishing between Mandarin and Spanish in the control condition than they do Italian and Spanish. With the initial experimental group data, we also found significant differences between groups across the exposure conditions revealing that language may play a beneficial role in children’s ability to discriminate between two similar sounding languages. Findings from our study may help us better understand what cues children use to decipher differences from foreign languages and what aspects of the environment children pay most attention to when growing up in bilingual environments.
    This research was performed in the laboratory of Professor Jenny Saffran
    Mihalec-Adkins, Brittany Purdue University

    Exploring the motivation to express prejudice: a scale validation

    In prejudice and stereotyping research, researchers have focused on why people want to avoid prejudice. This study examined whether some people are motivated to express prejudice. Participants were induced to write an essay either in favor of or against a racial diversity program, after which they reported their level of distress. They were then asked to evaluate an experimenter-constructed essay of the opposite stance and their own essay. People motivated to express prejudice were more likely to refuse to write an essay in favor of diversity. If they did agree to write a pro-diversity essay, they felt distressed, undermined the quality of their essay through tentative language, and evaluated their own essays poorly. In addition, these people rated the pro-diversity essays of others as poorer than anti-diversity essays. These results suggest that the motivation to express prejudice exists and is a distinct source of prejudicial behavior.
    This research was performed in the laboratory of Professor Trish Devine
    Nardi, Eliott University of Wisconsin-Madison

    Selective attention to motivationally significant drug stimuli: Differential effects of psychopathic and antisocial personality disorder symptoms

    Both psychopathy and antisocial personality disorder (ASPD) are associated with clinically significant levels of impulsive, irresponsible, and aggressive behaviors, but there is growing evidence that their disinhibited behaviors reflect different cognitive and affective influences on attention. Whereas psychopathy is associated with normal or superior selective attention, ASPD is associated deficits in selective attention, particularly in the presence of motivationally significant stimuli (Baskin-Sommers & Newman, 2013). Using a sample of substance abusing prison inmates, Bencic and colleagues (2013) recently examined selective attention to motivationally relevant (drug and alcohol) images using a dot probe task. Results from the dot probe task indicated that psychopathic offenders exhibited slower disengagement from motivationally relevant relative to neutral stimuli, but it was unclear whether this effect demonstrated heightened focus on salient cues or slower processing of the images. To disambiguate this finding, the current study used image recognition data from the dot probe task to determine whether psychopathy was also associated with enhanced memory for the pre-potent images. Using a signal detection analysis to assess specific memory for the relevant images, and controlling for the overlap between psychopathy and ASPD, psychopathy was associated with significantly greater sensitivity for relevant images (p < .02) whereas ASPD was associated with lower sensitivity at the trend level (p < .10). Overall, the findings of this study suggest that psychopathy is associated with a greater focus on pre-potent personally relevant stimuli, whereas the same stimuli tend to undermine the quality of information processing in other antisocial individuals.
    This research was performed in the laboratory of Professor Joseph Newman
    Riciputi, Shaina Colorado College

    Using text analysis to evaluate utility value

    Utility value (UV) is the perception that a task is valuable because it enables individuals to complete a present or future goal. Evidence suggests that UV interventions that prompt individuals to write about UV promote academic interest and performance, but it can be difficult to quantify UV. A dictionary was constructed using linguistics software to assess the degree to which people use categories of words across text files, to objectively measure and quantify UV expressed in essays written in a class. Dictionary words were selected based on how well they typified constructs used in past UV research. Utility words were used in conjunction with LIWC’s preprogrammed personal pronouns dictionary. Utility words marginally predicted participant exam score while pronouns predicted participants’ self-reported interest. These results help justify the use of linguistics software dictionaries to help understand UV in future utility research.
    This research was performed in the laboratory of Professor Judy Harackiewicz
    Rosen, Monica University of Central Florida

    Asymmetries in stereoscopic motion sensitivity across simple 3D environments

    Although there has been a great deal of research on binocular depth perception (Foley, 1980; Gogel, 1977), several important questions remain. For example, previous research has shown that participants judge approaching stimuli as moving too far to the side (i.e., more laterally) than they actually are (Harris & Dean, 2003). Furthermore, sensitivity to disparity information appears to vary according to where stimuli are presented relative to fixation (Woo and Sillanpaa, 1979; Becker, Bowd, Shorter, King, & Patterson, 1998). We hypothesize that our understanding of human perceptual ability to predict the trajectories of objects moving in depth has been limited to a small set of well-studied conditions. In the current study, we expanded upon those conditions and explored the interactions between varying contrast levels and motion direction (both approaching and receding) over three different stimulus configurations. We first replicated the lateral bias reported by Harris & Dean (2003) with only approaching stimuli shown at reduced contrast – high contrast stimuli were accurately estimated. We then revealed an asymmetry in motion-in-depth estimation, whereby no lateral bias was present in participants’ estimates of receding motion. Finally, the inclusion of additional configurations, which presented the stimuli at different positions relative to fixation, revealed that participants are generally better at estimating receding motion than motion approaching them. These results suggest that human motion estimation is not simply poor as implied by previous results. Instead, motion estimation is contingent upon the quality of visual information and whether the information arises from approaching or receding motion.
    This research was performed in the laboratory of Professor Bas Rokers
    Shields, Morgan Kent State University

    Processing positive emotional stimuli consciously and non-consciously: a study of behavior and peripheral physiology

    Processing of emotional stimuli has been shown to have different behavioral consequences during aware and unaware conditions. Physiological responses to negative stimuli during conditions of unawareness have been shown to predict emotional coloring in a negative direction (Lapate, Rokers, Li, & Davidson, in press). Very few studies have explored this phenomenon using positive stimuli. This study attempted to elucidate the behavioral consequences of aware and unaware processing of positive stimuli by simultaneously measuring peripheral-physiological responses and judgments of likability for novel neutral faces. During phase one, we examined the effectiveness of a wide array of positive stimuli in provoking peripheral-physiological changes and found that images of animals and happy faces elicited the greatest change in skin conductance and zygomaticus electromyographical responses. Phase two is ongoing and will address the behavioral consequences of unaware processing of positive stimuli. Thus, this study will enhance our understanding of the scope and limit of emotional information processing in the absence of visual awareness, and help elucidate the role of conscious awareness in emotional processing.
    This research was performed in the laboratory of Professor Richie Davidson

    * * *

    (Note: PREP research projects are typically part of larger studies that will be published in the peer-reviewed literature. The PREP Journal will present abstracts from student student research papers until the corresponding complete study has been published.)

    * * *

    This material is based upon work supported by the National Science Foundation under Grant No. 1004961.

    Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

  • 2012
    Aguirre, Claudia University of Southern California

    Alcohol’s Effect on Uncertain Reward

    Substantial empirical and anecdotal evidence indicate acute alcohol intoxication increases the frequency of risk-taking behaviors. Indeed, naturalistic and laboratory tasks of risk-taking behavior have successfully documented alcohol’s effects on risk-taking. However, naturalistic and traditional laboratory models of risk-taking are resistant to decomposition into elemental processes, and consequently do not permit strong inference about the specific mechanisms of alcohol’s effects on risk-taking behavior. The current study builds upon and advances this body of research, by incorporating formal economic formulations of risk as amount of variance in uncertain outcomes, with a gambling task that elicits strong approach motivation and engagement. On each trial of this novel task, participants chose to either gamble, and earn one of two equiprobable, but uncertain monetary offers, or to instead earn a certain, guaranteed, offer. The risk of choosing the uncertain offer was quantified as the variance of the two possible outcomes of the uncertain offer. We measured the probability of choosing the uncertain offer at two levels of variance, and administered alcohol, placebo, or no alcohol to 25 social drinkers. Preliminary analysis of preference for the uncertain offers revealed no significant effect of mean-variance. Further, no significant alcohol effects of pharmacology nor expectancy were detected. Despite these null-findings, trend-level effects of mean-variance and pharmacologic effects of alcohol suggest the current small sample size may limit the power of our analyses.
    This research was performed in the laboratory of Professor John Curtin
    Chaudhry, Kiren Wayne State University

    Gender and relational aggression in adolescence

    Relational aggression is defined as behavior that is used to damage relationships or uses the threat of damaging relationships to harm its victim. Relational aggression receives disproportionately less research than more overt forms of aggression. This longitudinal study examined gender differences in the frequency of relational aggression across adolescence, gender differences in negative affective responses to relational aggression, and gender differences in patterns of perpetration. Data from the Wisconsin Study of Families and Work was collected when the participants were ages 11, 13, 15 and 18, n = 315, n = 302, n = 268, and n= 256, respectively. Results indicated that there was no significant gender difference in frequency of victimization or trends over time. However, results supported gender differences in negative affect, such that at age 15 girls reported more negative affect associated with being victims of relational aggression than boys (a similar trend level effect was found at age 18). Chi square tests to determine patterns of perpetration at ages 15 and 18 revealed that the aggressor and victim were predominantly the same gender. Thus, contrary to societal stereotypes, gender similarities exist in the frequency of relational aggression victimization and trends in relational aggression over time. However, girls report being more upset than boys by relational aggression victimization.
    This research was performed in the laboratory of Professor Janet Hyde
    Efferson, Leah Hiram College

    Does stereotype threat underlie gender differences in self-reported empathy?

    For her PREP project, Leah Efferson had the opportunity to “get in on the ground floor” for a study examines the effect of stereotypes on gender differences in self-reported empathy. Leah’s work entailed designing the study, creating the stimuli, applying for and receiving IRB (i.e., “human research ethics”) approval, and collecting and analyzing data.
    This research was performed in the laboratory of Professor Morton Ann Gernsbacher
    Lee, Anita Amherst College

    Investigating the mechanisms of values affirmation-mediated achievement gap reductions

    Cultural mismatch theory has suggested that communally-oriented students experience a threatened self-perception upon entering a university culture that emphasizes individuality and independence (Stephens, 2012). The present study, conducted in a large-enrollment science class, tested the hypothesis that a values-affirmation intervention would effectively narrow the achievement gap by giving disadvantaged students the opportunity to reaffirm personal values and thereby reduce their sense of threat in an unfamiliar academic environment. For her PREP project, Anita worked on this ongoing project, learning to code students’ values affirmation essays for themes of independence and interdependence, and she learned how to analyze these data and manage large datasets.

    Maximo, Omar San Diego State University

    The effects of cognitive training on alpha-band power underlying visual short-term memory

    Visual short-term memory (VTSM) refers to the ability to retain information for a brief period of time, however, the underlying neural bases for VSTM capacity (i.e. the number of items held in memory) limitations is not well understood. One neural marker of individual differences in VSTM capacity can be derived from the EEG signal at posterior electrodes during the delay period of a VSTM task, called the contralateral delay activity (CDA), which scales with the number of items in memory and plateaus at a subject’s given VSTM capacity. Changes in the CDA have been loosely related to cortically-derived alpha band (8-12Hz) oscillations originating from posterior parietal brain areas, but a connection between capacity limitations and the alpha band has not been established. Working memory (WM) training has been shown to improve performance on the same and related tasks, and offers a novel method to study the neural bases of VSTM capacity limitations. In this study we used WM training to increase subjects’ VSTM capacities, and measured resulting changes in the CDA and spectrally-derived alpha band power. We hypothesized that if the CDA reflects the neural bases of VSTM capacity limits, then WM training-related increases in VSTM capacity would result in changes in the CDA amplitude. Furthermore, if the underlying neural basis of the CDA is tied to the alpha band, then WM training-related change in the CDA would be reflected in correlated change in alpha band power. Thirty healthy subjects were recruited for the study. Prior to training, we tested subjects on a VSTM task while simultaneously recording EEG. The CDA and alpha band power were derived from this signal. The experimental group underwent WM training while the control group underwent training on a nonmnemonic task (Tetris). All subjects trained for 25 days after which they underwent retesting on the pre-training task. Training increased VSTM capacity, reduced the CDA amplitude, and, in parallel, reduced alpha band power for the experimental group across memory loads. These results suggest that training increases the efficiency of information storage, via a reduction in a neural marker for individual differences in VSTM capacity, and that alpha band oscillations may underlie this effect.
    This research was performed in the laboratory of Professor Brad Postle
    Meussner III, Harry California State University, Fullerton

    Are obstetric complications related to autism? A twin study

    This study of 92 twins investigates the relationship between obstetric complications and autism diagnosis as well as the characteristics of autism. The twins were assessed using three obstetric complications scales as well as three scales on autistic traits. We compounded the obstetric factors into two composite scores defining mother’s complications and the twin’s individual complications. We hypothesized that birth complications would predict autism diagnosis as well as a higher level of autistic characteristics. A one way MANOVA as well as multiple regression models followed up by bivariate regressions provide evidence that only gestational age is a significant predictor of autistic traits while none of the birth factors studied predict autism diagnosis.
    This research was performed in the laboratory of Professor Hill Goldsmith
    Novacek, Derek University of Notre Dame

    A preliminary investigation of the relationship between schizotypal and autistic traits

    For his PREP project, Derek Novacek had the opportunity to participate in the beginning of a study that will examine the similarities and differences between autistic spectrum disorders and schizophrenia spectrum disorders using personality as well as biological measures. He gained experience in screening potential participants, obtaining informed consent, and collecting and analyzing pilot data.
    This research was performed in the laboratory of Professor Diane Gooding


    Oviedo Ramirez, Sandra California State University, San Marcos

    Psychostimulant action within the prefrontal cortex on sustained attention

    Low- dose psychostimulants, such as methylphenidate (MPH; Ritalin) and amphetamine (Adderall) are highly effective at calming behavior and enhancing cognitive function dependent on the prefrontal cortex (PFC) in patients with ADHD. These clinical actions of psychostimulants are consistent with evidence indicating ADHD is associated with a dysregulation of the PFC and extended frontrostriatal circuitry. Initially, the therapeutic effects of psychostimulants were thought to be unique to ADHD patients. However, extensive research demonstrates that psychostimulants improve PFC-dependent cognition and calm behavior in both normal human and animal subjects when administered at low and clinically-relevant doses. At these clinically-relevant doses, MPH was observed to increase catecholamine signaling preferentially within the PFC while higher doses progressively elevating catecholamine signaling outside the PFC. In previous work, we demonstrated that clinically-relevant doses of systemically administered MPH improve performance in a delayed-response task of working memory. Recent studies further demonstrated that although clinically-relevant doses of systemically administered MPH also improve sustained attention, this occurs at higher doses and involves different receptor mechanisms than that seen with working memory performance. These differences across tasks could indicate either an altered dose-dependent action within the PFC or that MPH acts outside the PFC to facilitate sustained attention. In recently completed work, we demonstrated that direct infusion of MPH into the dorsomedial PFC of rats improves performance in working memory similar to that seen with systemic administration. The present study was designed to investigate whether MPH acts directly within the PFC to improve sustained attention and whether the dose-response curve for this is right shifted.
    This research was performed in the laboratory of Professor Craig Berridge


    Pham, Tom University of Oklahoma

    Organization of vasopressin within the amygdala

    The peptide hormone vasopressin in mammals is associated with a variety of social behaviors including social-pair bonding, social recognition and aggression. In rats, males have higher expression of vasopressin than females in the amygdala and bed nucleus of the stria terminalis. Testosterone, a steroid hormone, is known to regulate this expression of vasopressin in rats, particularly during the neonatal period. However, the mechanisms that underlie how testosterone regulates vasopressin expression are currently unknown. One possibility that is being considered is an epigenetic mechanism known as DNA methylation. Recent research shows that higher methylation levels correlate to lower mRNA expression in the brain. In this experiment, neonatal rats are injected at birth with either estradiol, a metabolite of testosterone, or oil vehicle. After 13 days, brain samples are collected and analyzed for relative mRNA expression within the amygdala region of the brain, and DNA samples are analyzed to determine DNA methylation patterns. The results indicate that females injected with estradiol increased vasopressin mRNA levels to near male-typical levels. Furthermore, while methylation patterns were not fully analyzed in time, other data suggests that higher methylation levels did indeed correspond to lower levels of vasopressin mRNA expression within the amygdala. These findings offer some insight and possible direction into the impact of epigenetic mechanisms on biological function.
    This research was performed in the laboratory of Professor Anthony Auger


    Walker, Courtney Berea College

    Reading comprehension: Effects of SES and dialect on healthy literacy comprehension

    >Abstract coming soon!
    This research was performed in the laboratory of Professor Mark Seidenberg


    * * *

    (Note: PREP research projects are typically part of larger studies that will be published in the peer-reviewed literature. The PREP Journal will present abstracts from student student research papers until the corresponding complete study has been published.)

    * * *

    This material is based upon work supported by the National Science Foundation under Grant No. 1004961.

    Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

  • 2011
    Acevedo, Amanda Alverno College

    The effect of detailed instruction on autistic performance on the Wechsler Comprehension Subtest

    For her PREP project, Amanda Acevedo had the opportunity to “get in on the ground floor” for a study that will assess the effect of detailed instruction on autistic performance on the Wechsler Comprehension Subtest. The work entailed designing the study, creating stimuli, getting IRB (i.e., “human research ethics”) approval, and collecting and analyzing pilot data.
    This research was performed in the laboratory of Professor Morton Ann Gernsbacher


    Chang, Anna New York University

    Effects of testosterone on DNA methylation in the adult rat male brain

    Sexually dimorphic distinctions in brain anatomy and behaviors are induced by steroid hormones and created through epigenetic modifications, the alterations in gene expression by modulation of chromatin structure without changes to the DNA sequence. Specifically, DNA methylation is an epigenetic modification in which gene expression is repressed, and the process is initiated by the DNA methyltransferases DNMT1, DNMT3a, and DNMT3b. Once believed to be stable for life, these methylation patterns have been shown to be receptive to changes. Though much is known about testosterone’s effects on epigenetic modifications in the developing brain, not much is known about its effects in the adult brain. Therefore, we examined the effects of castration, thus the removal of testosterone from the hormonal milieu, on the mRNA expression levels of DNA methyltransferases DNMT1 and DNMT3a and demethylase GADD45b in the sexually dimorphic regions, the bed nucleus of the stria terminalis (BNST) and the amgydala, of the adult male rat brain. Through assessing relative mRNA expression levels, no differences of DNMT1, DNMT3a, or GADD45b were found between our castrated and sham castrated treatment groups. We conclude that the mRNA expression levels of DNA methyltransferases and methylase may not be an accurate reflection of the methylation activity induced by hormones.
    This research was performed in the laboratory of Professor Anthony Auger
    Haro-Garcia, Sonia Virginia Commonwealth University

    Children’s accuracy in assessing power from nonverbal behavior

    This study examined whether children can accurately assess or pay attention to nonverbal cues revealing power or dominance in naturalistic settings. Children rated videos about various power-related conversations and identified the individual in charge of the conversation. It is predicted that children will show considerable accuracy in identifying who was in charge or not, based on nonverbal behaviors depicted in the videos.
    This research was performed in the laboratory of Professor Kristin Shutts
    Johnson, Lacaya North Carolina A&T State University

    Understanding of equations: The effects of priming on undergraduates’ encoding and solving of Equivalence Problems

    Many children in the United States have a difficult time solving complex equations with operations on both sides of the equal sign (e.g., 3 + 4 + 5 = 3 + __). One reason for these difficulties is that children sometimes get stuck in a mental set due to the years of practice that they have had with the same problem solving strategies and problem structure. This mental set leads them to expect that problems will follow an “operations = answer” format, that the equal sign means “the total”, and that the best strategy to solve equations is to “perform all given operations on all given numbers” (McNeil & Alibali, 2005). Over time, children learn that these strategies do not always apply. The current study seeks to determine if there is a way to reactivate that knowledge in undergraduate students. Students were randomly assigned to six conditions in which they either received tasks designed to prime their knowledge of arithmetic patterns or control tasks. After priming, participants completed several tasks including an equation reconstruction task and an equation solving task. Priming did have a negative effect, not only on problem solving, but also on reconstruction (a measure of encoding). Although undergraduates have outgrown the mental sets and arithmetic patterns that they seem to have had as children, the information can easily be reactivated.
    This research was performed in the laboratory of Professor Martha Alibali
    Patel, Anushka Carleton College

    Discriminating facial emotion: Neural pathways in Autism Spectrum Disorders

    Recent research has found aberrant neural connectivity between functionally connected areas in autism spectrum disorders. Diffusion tensor imaging (DTI) offers a novel approach to studying functional connections by examining the integrity of structural connections — white matter tracts — between functionally connected regions. The research question of interest involves investigating the affective circuitry involved in atypical face processing in autism. Specifically, this study sought to corroborate the underconnectivity model by tracking major differences in the left and right uncinate fasciculus – a fiber bundle connecting the amygdala with the orbitofrontal cortex — in 13 autistic and 13 typically developing adolescents. There were no significant differences between the tracts or the groups, suggesting that aberrant functional activation may be intrinsic to the amygdala itself and does not extend to structural underconnectivity in regions surrounding it. The discussion addresses this study’s limitations and provides future directions for the findings.
    This research was performed in the laboratory of Professor Richie Davidson
    Stickel, Ariana San Diego State University

    Odor event related potentials (oERPs): A pilot study to capture detection of neutral, negative, and no odors

    There is an underrepresentation of scientific research in olfaction. Still less explored are olfactory ERPs–waveform representations of electrical activity conducted in specific areas of the brain after the presentation of an odor. The current study was an olfactory ERP pilot of five students who were given an odor detection task in which three different odor conditions (neutral, negative, and no odor) were presented and subjects responded “yes” or “no” as to whether they had smelled an odor. In addition to EEG collection, reaction times were recorded. Analysis revealed differences in reaction time for the detection of no odor as compared to negative and neutral odors. Waveform data may show greater amplitudes for no odor conditions as compared to neutral and negative conditions; however more analyses must be conducted to confirm.
    This research was performed in the laboratory of Professor Wen Li
    Ullsperger, Josie Ripon College

    The effect of timing of maternal and paternal psychopathology on children’s internalizing and externalizing behaviors

    This study examines the transmission of risk of psychopathology from parents to offspring through use of the Composite International Diagnostic Interview (CIDI) and the Berkeley Puppet Interview (BPI). The second focus of this study was to examine the influence of gender as a possible mediating factor in the relationship between parent and child mental health. Participants consisted of 654 twin pairs for which all required data was available including parent and child birth date, parent reports of lifetime diagnoses on the CIDI, and children’s responses on the BPI. Gender of the parent and the child proved to play a major role in the transmission of parent-to-child mental health problems. As expected boys showed more externalizing symptoms than girls; however, girls only showed more internalizing symptoms if their mothers had a disorder. Girls who had a mother with a disorder were more likely to show more extreme internalizing behaviors than girls of mothers who did not have a disorder. This relationship occurred for both mood and anxiety disorders. Boys whose mothers had a disorder did not show differences in internalizing behaviors as a function of maternal disorder status. Thus, there is a unique relationship between maternal internalizing disorders and their daughters. This could be due to genetics, social modeling, or daughter’s sensitivity to the stress of maternal mental health.
    This research was performed in the laboratory of Professor Hill Goldsmith
    Yang, Helen Hunter College

    Ultrasonic vocalizations in pair bonded Peromyscus californicus

    There are many kinds of courtship behaviors. In this study, we are interested in ultrasonic vocalizations (USVs) made by both female and male of the species Peromyscus californicus mice. Half of the pair bonded males were experienced and had already bonded with another female while the other half were naïve. The vocalizations made when the male and novel female were introduced were initially recorded. In this experiment, we recorded vocalizations again after the pair had been bonded for 3 months and some had litter(s) of pup(s). Unexpectedly, it was found that vocalizations, overall, had decreased. It was also found that the experienced males had heavier pups. Another experiment is currently being done where the females from this experiment are being paired with novel males to see if they exhibit the same behaviors.
    This research was performed in the laboratory of Professor Catherine Marler


    * * *

    (Note: PREP research projects are typically part of larger studies that will be published in the peer-reviewed literature. The PREP Journal will present abstracts from student student research papers until the corresponding complete study has been published.)

    * * *

    This material is based upon work supported by the National Science Foundation under Grant No. 1004961.

    Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.