Theses and Dissertations from UMD
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Item EFFECTS OF GROUP STATUS AND IDENTITY ALIGNMENT ON SOCIAL INFLUENCE(2024) Beavan, Kelly Ann; Lucas, Jeffrey W; Sociology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)A series of three studies examine effects of social identity alignment versus social status on influence within task groups. Status Characteristics Theory (SCT) predicts that deference will be given to high-status members, and Social Identity Theory (SIT) predicts deference to in-group members. This dissertation investigates conditions under which social status or identity alignment might be more predictive of deference by examining status characteristics that also constitute significant identities or memberships to a social in-group (e.g., race, gender). By discerning when social identity or status holds greater sway in task groups, results of three experimental studies shed light on influence dynamics and the interplay of status and social identity. The studies tested three mechanisms—degree of in-group identification, identity threat, and task importance—expected to be impactful in affecting the influence of high-/low-status, in-/out-group partners under varying conditions. Study 1 examines these processes in a minimal group setting (based on abstract groups based on “cognitive association styles”), and Studies 2 and 3 use more naturally-occurring social groups (e.g., home state in Study 2), such as those attached to an overarching status hierarchy (e.g., gender and race in Study 3). Each experiment had participants work with two (simulated) partners to complete a series of trials on an uncertain group task. This setting met the scope conditions for the theories I am applying to establish group structures: Participants were task and collectively oriented (SCT), were working on a task with no immediate feedback about performance and were explicitly told of categorical group differences between themselves and their partners (SIT). The instructions for Study 1 assigned participants to minimal groups based on bogus cognitive association styles. Study 2 used self-reported home state as a group-differentiating characteristic, and finally, Study 3 tested theorized processes with gender and race. Hypothesis 1 predicted that high-status partners would exert more influence than low-status partners and found partial support in Studies 2 and 3, primarily driven by the influence of high-status (in-group) partners over subjects. Hypothesis 2 predicted that in-group partners would have more influence than out-group partners, and results generally supported this by revealing strong influence from in-group partners, regardless of status (although in-group high-status partners were most influential in Studies 2 and 3). Hypothesis 3, which expected heightened task importance to increase deference to high-status others, did not receive strong empirical or theoretical support and was only directly manipulated in Study 1. Hypothesis 4 predicted that under threat to group identity, the effects of group membership on influence would increase relative to that of status. Contrary to expectations, results revealed that identity threat significantly increased the influence levels of high-status partners, even when that high-status meant out-group membership. These findings suggested that identity threat did not heighten the SIT-based effects on social influence (i.e., in-group influence), as predicted, and in some ways point to an SCT-based explanation (i.e., high-status influence) under threat. Hypothesis 5, predicting that identification to the in-group would increase the impact of group membership, relative to that of status, on outcomes of social influence, was strongly supported in Studies 1 and 3. Participants who more highly identified with their in-group accepted greater influence from their in-group (compared to out-group) partners, regardless of that in-group’s relative (high- or low-) status. An SIT interpretation of this finding suggests that low-status in-group members who more highly identify with their (e.g., racial, gender) in-group may not necessarily be more influenced by similar in-group others simply because of their shared group membership. They do, however, appear to be significantly less influenced by out-group others (even when that out-group is higher-status), a finding consistent with my predictions on in-group identification. Finally, Hypothesis 6, predicting in-group identification to moderate the relationships between task importance (6a) and identity threat (6b) on social influence, found mixed support. More highly-identified participants were more influenced by in-group partners (compared to their out-group counterparts), and in-group identification significantly and directly predicted influence above and beyond effects from experimental manipulations. Results from the three studies show that subtle features of the group context (identity threat and heightened in-group identification) affect how much influence (high- and low-status) group members exert over individuals. Findings from this research highlight the complex interplay between status, group membership, identification and threat in shaping social influence dynamics, and I conclude by using these results to evaluate the relative strength of status-based (SCT) versus identity-based (SIT) processes in driving outcomes of social influence.Item CORTICAL AND STRIATAL MECHANISMS OF VALUE-BASED DECISION-MAKING AND THEIR DISRUPTION IN ADDICTION(2022) Hadfield, Heather; Roesch, Matthew R; Neuroscience and Cognitive Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)For decisions both great and small, the brain utilizes an extensive network that integrates value assessment, reward prediction, and motivation to quickly and efficiently select the most beneficial option while minimizing aversive consequences for ourselves. Numerous psychiatric conditions, in particular drug addiction, can disrupt this network and impair decision-making behavior. It is therefore important to understand the neural underpinnings of decision-making and how neural activity and its associated behavior are disrupted by drugs of abuse. My dissertation will expand on current studies of this circuitry by examining epigenetic and neurophysiological mechanisms of value-based decision-making within two regions of the brain. In my final aim, I explore a new behavioral assay that may be used to study these and other regions relevant for value-based decision-making in the context of another complex behavior.In my first aim, I have recorded from single neurons in the rat dorsal lateral striatum (DLS) after overexpressing histone deacetylase 5 (HDAC5), an epigenetic enzyme implicated in incubation of craving, in the dorsal striatum (DS). In my second aim I used pharmacological lesion and single-neuron recording combined with cocaine self-administration techniques to study anterior insula, a region well-known for combining internal and external experience but largely under-studied in the context of higher cognitive processes. These studies were conducted while rats performed an odor-guided decision-making task in which the value of rewards were manipulated by either the delay to or the size of the reward across a series of trial blocks. I have found overexpression of HDAC5 in DS promoted inflexible, faster, and automatic behavior in the decision-making task while increasing DLS’s response to reward cues- similar to previous studies examining DLS activity and behavior after cocaine self-administration. In my studies of insula, I found recording from this region novel, global signals of reward value that seemed to reflect the overall structure of the behavioral task. Following cocaine-exposure, these signals were diminished while immediate rewards were over-represented on a trial-by-trial basis, leading to steeper discounting of delayed rewards. Additional studies lesioning this region promoted faster reaction times and increased goal-directed behavior. Together, these results provide insights into how drugs of abuse may impair behavioral flexibility and the tracking of long-term changes in reward from multiple mechanisms. However, it is still unknown how these changes in value assessment give rise to complex impairments of behavior. As a first step to addressing this issue, I used a new task to examine how chronic drug use- which disrupts both neural signals in the corticostriatal circuit and epigenetic enzymes- also impairs the complex ability to delay gratification. This final study replicated well-established findings of drug-induced reversal-learning impairment, but surprisingly did not alter decision-making. This collection of work demonstrates the complexity with which drug exposure alters neural circuitry and value-based decision-making, and additionally shows the importance of utilizing complex behavioral assays to explore the relationship between brain and behavior.Item HOW AND WHEN SIGNALING IMPACTS CONSUMPTION(2021) Kim, Nicole You Jeung; Ratner, Rebecca K.; Wang, Yajin; Business and Management: Marketing; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)This dissertation includes three essays that investigate the impact of signals that certain consumption choices can send to other consumers. In particular, each essay focuses on how consumers’ consumption-related decisions (e.g., choice of hedonic items, selecting low variety, and communicating that one has no preference) impact an observing audience’s perceptions of the consumer and the subsequent impacts on the observer. The first essay demonstrates that consumers strive to position themselves as attractive friends by making hedonic consumption decisions. While consumers shift to hedonic consumption, anchoring on their belief that others would heavily value fun when it comes to friendship, this essay demonstrates that consumers themselves actually value other aspects of friendship more, such as meaningfulness. As a result of this discrepancy in the belief of friendship, hedonic choice does not effectively help consumers cultivate friendship with another person. The second essay investigates the signals that selecting a low (vs. high) variety of items sends to observers. Choosing low variety signals to observers that the consumer has accumulated consumption experiences in the past, and thus has greater expertise, compared to choosing high variety. This signal of expertise endows the consumer with influence to impact observers to make consumption choices that mimic the consumer and be more willing to take the consumer’s recommendations. The third essay examines the impact of expressing no preference in a joint decision making context. While consumers expect to make the decision easier for the recipient, recipients of no preference communication (vs. explicit preference communication), experience greater decision difficulty. This unexpected negative impact occurs because recipients of no preference communication perceive that the communicator actually has preferences that they are hiding. Further, because recipients infer that these hidden preferences are dissimilar to one’s own preferences, they end up making a choice for the joint consumption that they personally less prefer.Item SECOND LANGUAGE LEXICAL REPRESENTATION AND PROCESSING OF MANDARIN CHINESE TONES(2018) Pelzl, Eric; DeKeyser, Robert; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)This dissertation investigates second language (L2) speech learning challenges by testing advanced L2 Mandarin Chinese learners’ tone and word knowledge. We consider L2 speech learning under the scope of three general hypotheses. (1) The Tone Perception Hypothesis: Tones may be difficult for L2 listeners to perceive auditorily. (2) The Tone Representation Hypothesis: Tones may be difficult for L2 listeners to represent effectively. (3) The Tone Processing Hypothesis: Tones may be difficult for L2 listeners to process efficiently. Experiments 1 and 2 test tone perception and representation using tone identification tasks with monosyllabic and disyllabic stimuli with L1 and advanced L2 Mandarin listeners. Results suggest that both groups are highly accurate in identification of tones on isolated monosyllables; however, L2 learners have some difficulty in disyllabic contexts. This suggests that low-level auditory perception of tones presents L2 learners with persistent long-term challenges. Results also shed light on tone representations, showing that both L1 and L2 listeners are able to form abstract representations of third tone allotones. Experiments 3 and 4 test tone representation and processing through the use of online (behavioral and ERP) and offline measures of tone word recognition. Offline results suggest weaknesses in L2 learners’ long-term memory of tones for specific vocabulary. However, even when we consider only trials for which learners had correct and confident explicit knowledge of tones and words, we still see significant differences in accuracy for rejection of tone compared to vowel nonwords in lexical recognition tasks. Using a lexical decision task, ERP measures in Experiment 3 reveal consistent L1 sensitivity to tones and vowels in isolated word recognition, and individual differences among L2 listeners. While some are sensitive to both tone and vowel mismatches, others are only sensitive to vowels or not at all. Experiment 4 utilized picture cues to test neural responses tied directly to tone and vowel mismatches. Results suggest strong L1 sensitivity to vowel mismatches. No other significant results were found. The final chapter considers how the three hypotheses shed light on the results as a whole, and how they relate to the broader context of L2 speech learning.Item LEARNING PROCESSES UNDERLYING IMPLICIT MOTOR SEQUENCE ACQUISITION IN CHILDREN AND ADULTS(2016) Du, Yue; Clark, Jane E; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Children and adults are able to learn a motor sequence quickly, usually over a course of one learning session consisting of 4-8 learning blocks. This initial acquisition is referred to as fast learning. However, little is known about the learning processes underlying the fast acquisition of motor sequences. Therefore, the overarching objective of this dissertation was to examine the underlying processes that drive rapid motor sequence learning in children and adults. In a series of studies, children and adults performed a modified serial reaction time (SRT) task, a primary window into understanding implicit motor sequence learning. Study I demonstrated that fast learning of implicit motor sequences in six- and 10-year-old children was comparable to adults, while the performance (i.e., reaction time, RT) during learning was reflected by two age-related processes. Learning in six-year-old children dominantly relied on an offline process where RT improved after a short rest, while offline enhancement as well as online progressive improvement in RT reflected sequence learning in 10-year-old children and adults. In studies II, III, and IV, we demonstrated that the online and offline processes were neither by-products of task pacing constraints nor illusory effects of fatigue or reactive inhibition. Instead, these two age-related processes were more likely to be functional mechanisms underlying implicit motor sequence learning, which could be modulated by the involvement of procedural and declarative memory. In addition, study III characterized the developmental landscape of 5- to 14-year-old children and found that the developmental changes of online and offline learning were primarily present in early childhood. As fast learning is known to enable generalization (or transfer) of sequences learning, we expected, given the findings in studies I through IV, age-related differences in the generalization of implicit motor sequence learning. The results in study V, interestingly, demonstrated that the generalization of implicit motor sequence learning was better in children than in adults. However, in study VI, when greater procedural memory was required in the SRT task, learning in adults largely depended on offline learning; and, the age-related differences in learning generalization vanished, suggesting that offline learning may facilitate the generalization of implicit motor sequence learning. Taken together, results from these studies found two age-related learning processes (i.e., online and offline learning) that drive the fast implicit sequence acquisition and demonstrated that the age-related online and offline learning may lead to children a superior ability in the generalization of motor sequence learning. These results extend our understanding of the age-related development of implicit motor sequence learning and provide potential insights into the question of why childhood is an optimal period for learning.Item THERAPIST-CLIENT RACIAL MATCHING VS. NON-MATCHING AND THERAPISTS’ COUNTERTRANSFERENCE: EXPLORING THEIR RELATION AND TESTING MODERATORS.(2016) Palma Orellana, Beatriz Isabel; Gelso, Charles J.; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The present study assessed the influence of clients’ race (i.e., Black/African American or White/European American), therapists’ universal-diverse orientation (UDO), and therapists’ anger discomfort on countertransference reactions. Countertransference was operationalized as therapists’ self-reported state anxiety, their verbal avoidant responses (as manifestation of behavioral countertransference), and their self-reported countertransference. Data were gathered from 63 White, European American therapists and therapists-in-training. Participants completed online measures pertaining to universal-diverse orientation, anger discomfort, trait anxiety, social desirability, and a demographic questionnaire. A week after completing such measures, the participants completed a Lab session. The therapists and therapists-in-training were randomly assigned to one of two conditions: An angry White/European American client or an angry Black/African American client. Participants watched and verbally responded to a video of the assigned scripted analogue client. Right afterward, the therapists and therapists-in-training completed a measure of state anxiety and three single items assessing the influence of the participant’s countertransference in his or her behaviors, thoughts, and feelings while responding to the videotaped client. Additionally, the participants’ verbal responses were transcribed verbatim and coded as approach or avoidant responses, which ultimately provided an index of behavioral countertransference. Results showed that therapists’ anger discomfort, their universal-diverse orientation, clients’ race, and interaction terms (clients’ race X UDO and clients’ race X anger discomfort) predicted state anxiety. However, in this model, only anger discomfort was statistically significant. No significant effects were found on the other countertransference measures. Additionally, only anger discomfort significantly and uniquely accounted for variance in state anxiety. Contrary to expectations, neither clients’ race nor universal-diverse orientation uniquely accounted for variance in the dependent variables. Results were not significant for the interaction of clients’ race and UDO on therapists’ countertransference reactions. Results were also non-significant for the interaction of clients’ race and anger discomfort on the participants’ countertransference reactions. Implications of the findings are further discussed.Item A factorial study of incentives in certain learning and performance situations(1949) Matheny, William Guy; Digital Repository at the University of Maryland; University of Maryland (College Park, Md)Item The effects on thematic apperception of certain experimentally aroused needs(1951) Field, William Franklin; Digital Repository at the University of Maryland; University of Maryland (College Park, Md)Item Prediciting the reporting ability of test subjects(1952) Abelson, Herbert Irving; Digital Repository at the University of Maryland; University of Maryland (College Park, Md)Item EXPERIMENTAL MEASUREMENT OF BEHAVIORAL APPROACH MOTIVATION IN MAJOR DEPRESSIVE DISORDER(2015) SZCZEPANIK, JOANNA; LEJUEZ, CARL W; Neuroscience and Cognitive Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Major Depressive Disorder (MDD) presents a significant public health challenge. Given the symptoms heterogeneity and widespread changes in brain structure and Function in MDD, there may be several subtypes of depression not sufficiently distinguished by current diagnostic criteria but important to recognize to improve clinical outcomes. One of the two core symptoms of MDD is `markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day' and is often referred to as anhedonia (DSM-IV, V). Anhedonia may have a variety of underlying causes such as not finding previously enjoyed activities appealing, lacking motivation to engage or reluctance to put forth necessary effort, and these processes may be quite unique and not differentiated by current assessment methods (Treadway & Zald, 2011). It has been long recognized that depression is associated with insufficient environmental reinforcement (Peter M. Lewinsohn & Graf, 1973) and treatments were developed to address this deficiency (Peter M. Lewinsohn, Sullivan, & Grosscup, 1980). Clinical studies of effectiveness of the Behavioral Activation Treatment for Depression (BATD), (Hopko, Lejuez, LePage, Hopko, & McNeil, 2003), suggest that an increase in the engagement in reinforcing activities may be helpful in treatment of depression. However, a crucial aspect of activity related behavior, the initial approach and engagement which necessarily precede potential experience of enjoyment, has not been sufficiently characterized. In the current work, we present the development of an experimental behavioral approach motivation paradigm (BAMP) to study approach motivation to engage in liked activities, and relate experimental results to the symptoms of depression and anhedonia to better characterize approach behavior in MDD. We sought to establish a valid behavioral measure of approach motivation in major depression that will be suitable for behavioral and neuroimaging studies of anhedonia. In the BAMP study, subjects rated activity words for the appetitive value, and later `approached' and `avoided' the stimuli in an implicit joystick task. The findings indicated reduced range of activities rated as liked by depressed patients versus healthy controls, but no difference on an approach measure of liked activities. The depressed group showed a stronger approach rather than avoidance of disliked activities. Thus, `lack of interest or pleasure' may be partially related to excessive approach of mood-maintaining negative experiences, and inadequate avoidance of disliked situations. Further study of altered approach and avoidance behavior could shed additional light on processes underlying anhedonia in Major Depressive Disorder.