Alumni Dissertations

 

Alumni Dissertations

Filter Dissertations By:

 
 
  • ACUTE EFFECTS OF ESTROGEN AND BISPHENOL-A, AN ENVIRONMENTAL CHEMICAL, ON COGNITIVE AND NEURAL FUNCTION

    Author:
    Tomoko Inagaki
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Victoria Luine
    Abstract:

    Many natural and synthetic chemicals in environment can mimic or antagonize the effects of endogenous hormones. Bisphenol A (BPA) is one such chemical, with mixed estrogen agonist/antagonist properties. Recent evidence indicates that estrogen and BPA may exert effects on brain functions not only through genomic but also through non-genomic pathways, activating membrane-associcated estrogen receptors. Because at present little is known about how acute BPA may interact with estrogen in the adult brain and affect estrogen mediated behaviors such as memory and learning, this research examined acute effects of estradiol (E2) and BPA, alone, and in combination, on behavior (memory consolidation) and neural function (spine density and monoamine levels) in adult ovariectomized female rats. For behavioral study, acute 17beta- and 17alpha-E2 treatment effects on spatial and non-spatial memory consolidation were tested using object placement (OP) and object recognition (OR) tasks. Both isomers of estradiol facilitated memory consolidation, but enhancement occurred in a time-, dose-, and task specific manner. The dose-response relationship was an inverted-U for both tasks. Co-administration of BPA blocked E2-induced OP memory enhancement far below the current reference safe dose of 50ug/kg/day. A larger BPA dose was needed to block 17alpha-E2 induced OR memory enhancement. BPA alone had no effect on OP memory, but high doses enhanced OR memory. To examine possible neural systems that may contribute to acute E2 and BPA treatment effects, brains were removed for neuromorphological and neurochemical analysis. Golgi impregnation 30 minutes after acute treatments showed that E2 increased apical and basal dendritic spine density in pyramidal neurons of of the prefrontal cortex (PFC), and basal, but not apical, spine density in pyramidal neurons of CA1 region of the hippocampus. Co-administration of BPA with E2 further increased apical and basal spine density in both the PFC and the CA1. Golgi impregnation 4 hours after acute treatments found that co-administration of BPA significantly suppressed E2-induced basal CA1spine density. Neurochemical analyses revealed that acute estrogen increased monoamine and metabolite levels in the PFC, but decreased these chemicals in the hippocampus. Co-administration of BPA further increased monoamine and metabolite concentrations in the PFC. In summary, the current data provide new information about acute effects of estrogen and BPA on memory and brain function. BPA interacts with E2 at very low doses, and rapidly alters behavioral and neural response to E2. These findings demonstrate BPA behavioral changes at very low doses in the membrane environment and suggest low level exposure of BPA may have a powerful, negative impact, rapidly altering behavioral and neural responses to endogenous estrogen.

  • Symbolic Ruptures: The Speech and Language of Trauma

    Author:
    IOANNA IOANNOU
    Year of Dissertation:
    2009
    Program:
    Psychology
    Advisor:
    Lissa Weinstein
    Abstract:

    This dissertation project is a theoretical examination of `symbolic ruptures,' the traumatic disruptions in human experience that resist being represented in ordinary modes of symbolization. Insofar as the representation of such disturbing experiences is primarily non-verbal, it has been often relegated to the realm of the `desymbolic.' This project attempts to re-conceptualize the forms and symptoms in which such experiences are expressed as an unconscious language and seeks to reinstate them back into the realm of the symbolic, thus creating a new imperative for their understanding. While mainstream psychoanalytic literature has regarded symbolization as a representational process, this project expands the use of the term to connote the range of experiences and processes that connect the subject to the symbolic structures of a culture. In this sense, `symbolic ruptures' not only affect one's capacity to represent extraordinary experiences in thought and in language, but they fundamentally disrupt the subject's link to the world. It is argued, however, that the symptoms of these ruptures-- the recurring nightmares, the flashbacks, the hallucinatory experiences, etc.--remain symbolic in that they constitute an address to an other that seeks to be heard. While these symptoms may conceal or silence the traumatic event, their repetitive nature expresses the structure of the trauma. It is through the ruptures in the structure of the treatment and of the clinical setting, it is argued, that the structure of trauma may be accessed. This theoretical framework, which is highly informed by French psychoanalysis and the work of Jacques Lacan, ultimately aims to expand the way we understand and work with experiences of trauma in the clinical setting. In undertaking this project, I also hope to challenge existing views on symbolization by deemphasizing the importance of verbal representation and recognizing the symbolic potential in the non-verbal language of symptoms.

  • Symbolic Ruptures: The Speech and Language of Trauma

    Author:
    IOANNA IOANNOU
    Year of Dissertation:
    2009
    Program:
    Psychology
    Advisor:
    Lissa Weinstein
    Abstract:

    This dissertation project is a theoretical examination of `symbolic ruptures,' the traumatic disruptions in human experience that resist being represented in ordinary modes of symbolization. Insofar as the representation of such disturbing experiences is primarily non-verbal, it has been often relegated to the realm of the `desymbolic.' This project attempts to re-conceptualize the forms and symptoms in which such experiences are expressed as an unconscious language and seeks to reinstate them back into the realm of the symbolic, thus creating a new imperative for their understanding. While mainstream psychoanalytic literature has regarded symbolization as a representational process, this project expands the use of the term to connote the range of experiences and processes that connect the subject to the symbolic structures of a culture. In this sense, `symbolic ruptures' not only affect one's capacity to represent extraordinary experiences in thought and in language, but they fundamentally disrupt the subject's link to the world. It is argued, however, that the symptoms of these ruptures-- the recurring nightmares, the flashbacks, the hallucinatory experiences, etc.--remain symbolic in that they constitute an address to an other that seeks to be heard. While these symptoms may conceal or silence the traumatic event, their repetitive nature expresses the structure of the trauma. It is through the ruptures in the structure of the treatment and of the clinical setting, it is argued, that the structure of trauma may be accessed. This theoretical framework, which is highly informed by French psychoanalysis and the work of Jacques Lacan, ultimately aims to expand the way we understand and work with experiences of trauma in the clinical setting. In undertaking this project, I also hope to challenge existing views on symbolization by deemphasizing the importance of verbal representation and recognizing the symbolic potential in the non-verbal language of symptoms.

  • Transfer of oddity-from-sample performance in the pigeon to novel stimulus locations

    Author:
    Zaur Isaakov
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Robert Lanson
    Abstract:

    The study examined the role of stimulus location in oddity-from-sample conditional discrimination in the pigeon. A three-key discrimination procedure with vertical and horizontal lines was used. The two phases of the experiment were carried out using two groups of four pigeons. One group was trained with the sample stimulus always appearing on the center key. After a response to the sample stimulus, two comparison stimuli were presented on the remaining two keys. The second group was trained with the sample presented on one of the side keys. After a peck to the sample key, the comparisons were presented on the remaining two keys. Following acquisition of oddity, the procedures were reversed between the two groups. The birds' performance was analyzed in terms of both multiple-rule and single-rule models of conditional discrimination. The results show that oddity-from-sample conditional discrimination is best described in terms of specific, sample-comparison associations, where the location of the stimuli must be specified.

  • Transfer of oddity-from-sample performance in the pigeon to novel stimulus locations

    Author:
    Zaur Isaakov
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Robert Lanson
    Abstract:

    The study examined the role of stimulus location in oddity-from-sample conditional discrimination in the pigeon. A three-key discrimination procedure with vertical and horizontal lines was used. The two phases of the experiment were carried out using two groups of four pigeons. One group was trained with the sample stimulus always appearing on the center key. After a response to the sample stimulus, two comparison stimuli were presented on the remaining two keys. The second group was trained with the sample presented on one of the side keys. After a peck to the sample key, the comparisons were presented on the remaining two keys. Following acquisition of oddity, the procedures were reversed between the two groups. The birds' performance was analyzed in terms of both multiple-rule and single-rule models of conditional discrimination. The results show that oddity-from-sample conditional discrimination is best described in terms of specific, sample-comparison associations, where the location of the stimuli must be specified.

  • An Analysis of Mulit-Media Representations of Children's Experience of War by Humanitarian Organizations

    Author:
    Aida Izadpanahjahromi
    Year of Dissertation:
    2012
    Program:
    Psychology
    Advisor:
    Colette Daiute
    Abstract:

    This research examines some of the processes humanitarian organizations use to represent war-affected children. Employing discourse analysis of online imagery guided by principles of the UN Convention on the Rights of the Child and theories of child development in war, this study analyzes multi-media representations of war-affected youths in Iraq and Afghanistan from the websites of four humanitarian organizations: The United Nations High Commissioner for Refugees (UNHCR), International Rescue Committee (IRC), War Child Canada, and Photo-voice (UK). I augment this analysis with a sampling of interviews of key informants to gain their insights about this imagery on their websites. This analysis comprises a complex system of signification that represents and communicates via three interrelated mediational components comprised of mission statements, visual archives, and reflections of key informants within each humanitarian organization. The study assesses humanitarian organizations' ability to foreground the perspectives of war-affected children and their families and to recognize the extent to which these representations reflect diverse and complex experiences of such children in the context of everyday life. This interdisciplinary approach looking across time and context, illuminates some degree of contradiction, even counter-productiveness, between the means and ends of some humanitarian organizations. Systematic analysis based on criteria from the U.N. CRC and on reflections of key informants, indicates that many images of war-affected children foreground economic and public interests (e.g., fundraising, media attention) or the interest of awareness (e.g., lobbying) at the expense of rendering passive the subjects of these images. While such a complex system of signification may appeal to donors and public awareness of sympathy, it also downplays or denies children's right to participate in their own representation and social change. Analysis of these mediational components explains how such images construct specific views of humanitarian organizations about the photographed children, clarifies the power dynamics within each organization, and the criteria in producing and choosing images. In addition to findings about the nature of images of representing children growing up in war circumstances, this dissertation contributes an analytic framework that humanitarian organizations may use to assess their multi-media communications.

  • African American Acculturation and Its Relationship to Subjective Well-Being in African American Women

    Author:
    Sharlene Jackson
    Year of Dissertation:
    2011
    Program:
    Psychology
    Advisor:
    Vera Paster
    Abstract:

    The study, African American Acculturation and Its Relationship to Well-Being in African American women, investigated how African American women maintain a sense of well-being in spite of their devalued social status. One hundred-and-one, middle class, African American women from across the United States completed a demographic questionnaire, the African American Acculturation Scale (AAAS), the Cross Racial Identity Scale (CRIS), the Index of Race-Related Stress (IRRS), the Ways of Coping Questionnaire (WOCQ), the Multidimensional Scale of Perceived Social Support (MSPSS) and the Satisfaction with Life Scale (SWLS). Women reporting greater affiliation with black culture and valuing of black identity reported more race-related stress, however, traditional acculturation status and an internalized black identity were not independent predictors of social support, coping efforts or well-being. An identity dominated by attitudes of black self-hatred was a significant, positive predictor of increased efforts at coping and black self-hatred was strongly and negatively correlated with well-being. Although, acculturation status was not an independent predictor of more frequent coping or greater well-being, traditional religious beliefs and practices were strongly and positively correlated with more frequent coping efforts and greater reports of well-being.

  • Parental Reflective Functioning and the Development of Self-Regulation: An Examination of the Relationship between Parental Reflective Functioning and Children's Capacity to Delay Gratification

    Author:
    Melissa Jacobs
    Year of Dissertation:
    2014
    Program:
    Psychology
    Advisor:
    Arietta Slade
    Abstract:

    The ability to voluntarily delay gratification is viewed as a fundamental component of the developing self-regulatory capacities of a young child. Mischel and his colleagues' "marshmallow test" is a simple laboratory procedure designed to simulate the difficulty of voluntarily delayed gratification that has come to be viewed as a powerful diagnostic tool for illuminating stable and consequential individual differences. Fonagy and his colleagues' concept of mentalization (1991), operationalized as reflective functioning (RF), views self-regulation and mentalization as inextricably linked, emerging from one another. Parental reflective functioning (Slade, 2005) assesses a parent's capacity to mentalize about her child. The present study aimed to test the hypothesis that higher levels of parental RF as assessed on the Parent Development Interview (PDI) would be associated with better delay performance on Mischel's self-imposed delay of gratification procedure, as measured by the amount of time the child is able to delay gratification, while the children of parents who exhibit lower levels of parental RF would delay for shorter periods of time on the delay task. The study found no evidence of a relationship between parental RF and the length of time a child was able to delay gratification. These results are discussed in terms of their implications for future research into the development of self-regulation in young children, as well as for attachment and mentalization theory and research.

  • The Effects of Pairing Preferred Stimuli with Non-preferred Staff on the Reinforcing Value of Non-preferred Staff Attention

    Author:
    Jared Jerome
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Peter Sturmey
    Abstract:

    Establishing staff attention as a secondary reinforcer increases the amount of time individuals with intellectual disabilities will engage in on-task behavior when working with these staff; however, increasing the reinforcing value of staff attention by pairing it with primary reinforcing stimuli is an area of research that has not frequently been addressed. In Study 1, three residents aged 42 to 56 years and diagnosed with intellectual disabilities participated in verbal and pictorial preference assessments for staff members. All three residents showed preferences. The experimenter then validated these preferences by instructing the preferred and non-preferred staff to deliver verbal praise and a high five on a progressive-ratio schedule contingent on the completion of socially relevant tasks. All three residents demonstrated higher break points and rates of approach responses when they were attended to by their preferred staff compared to when they were attended to by their non-preferred staff. In Study 2, before each baseline session, non-preferred staff approached the residents on a VT 1 min schedule without presenting any tangible stimuli; break points and approach responses remained unchanged from Study 1. Before each intervention session, non-preferred staff approached the residents on a VT 1 min schedule while presenting them with preferred tangible stimuli. Break points and resident-rate-of-approach responses increased when they worked for attention from their non-preferred staff, but remained unchanged with their preferred staff. A pairing procedure was successful in improving the relationships between residents and previously non-preferred staff.

  • The Effects of Pairing Preferred Stimuli with Non-preferred Staff on the Reinforcing Value of Non-preferred Staff Attention

    Author:
    Jared Jerome
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Peter Sturmey
    Abstract:

    Establishing staff attention as a secondary reinforcer increases the amount of time individuals with intellectual disabilities will engage in on-task behavior when working with these staff; however, increasing the reinforcing value of staff attention by pairing it with primary reinforcing stimuli is an area of research that has not frequently been addressed. In Study 1, three residents aged 42 to 56 years and diagnosed with intellectual disabilities participated in verbal and pictorial preference assessments for staff members. All three residents showed preferences. The experimenter then validated these preferences by instructing the preferred and non-preferred staff to deliver verbal praise and a high five on a progressive-ratio schedule contingent on the completion of socially relevant tasks. All three residents demonstrated higher break points and rates of approach responses when they were attended to by their preferred staff compared to when they were attended to by their non-preferred staff. In Study 2, before each baseline session, non-preferred staff approached the residents on a VT 1 min schedule without presenting any tangible stimuli; break points and approach responses remained unchanged from Study 1. Before each intervention session, non-preferred staff approached the residents on a VT 1 min schedule while presenting them with preferred tangible stimuli. Break points and resident-rate-of-approach responses increased when they worked for attention from their non-preferred staff, but remained unchanged with their preferred staff. A pairing procedure was successful in improving the relationships between residents and previously non-preferred staff.