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EXAMINING SPATIAL RESOLUTION, STIMULUS PERCEPTION AND RELATIVE CONTRIBUTIONS OF THE OCTAVOLATERALIS SUB-SYSTEMS OF THE GOLDFISH (CARASSIUS AURATUS)
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In two separate series of behavioral experiments, spatial resolution and perceptual dimensions corresponding to physical stimulus attributes (frequency, amplitude and position) of a vibratory dipole source were assessed using classically conditioned respiratory suppression in goldfish (Carassius auratus).
Reflective Functioning and Differentiation-Relatedness During Pregnancy and Infant Attachment Outcomes at One Year
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This study compared maternal reflective functioning (RF) and differentiation-relatedness (DR) during pregnancy and examined how these processes relate to the quality of mother-infant attachment at one year. The subjects were 35 mother-infant pairs drawn from the control group of a longitudinal treatment study, "Minding the Baby (MTB)," a federally and privately funded home intervention program developed jointly by the Yale School of Nursing and Yale Child Study Center, led by Drs. Lois Sadler and Arietta Slade, and targeting a low socio-economic status area of New Haven, CT. The Pregnancy Interview (Slade, 2003) was administered to the women (ages 14-25 years) during the third trimester of pregnancy, and quality of attachment was assessed when infants were 14 months using the Strange Situation (Ainsworth, Blehar, Waters, & Wall, 1978; Main & Solomon, 1990). The DR scoring system, the Differentiation-Relatedness Scale of Self and Object Representations (Diamond, Blatt, Stayner, & Kaslow, 2011), was adapted for use with the Pregnancy Interview to provide a manual for this study (Daley, 2012). Lowest, highest, and most typical DR ratings were captured for self, the woman's mother, the father of the baby, and the baby. The mean for the baby, at 3.03, was one DR point lower than other relationship means. Three composite scores were created, averaging across relationships: Low DR, High DR, and Overall DR. Results indicated that maternal RF was correlated with Overall DR and High DR; however, none of these variables distinguished between attachment outcomes. In contrast, Low DR distinguished, with a large effect size (d = .92), between disorganized and secure attachment outcomes (p = .026), and, in post-hoc analyses, between disorganized and all organized outcomes. For the disorganized group, Low DR often dropped to self-other boundary confusion (level 2) across relationships. This suggests that, for a population of women on the lower end of the RF Scale, transient regression to non-differentiated states during pregnancy is a risk factor for disorganized infant attachment outcomes at one year. Results have implications for early identification of high-risk dyads and refinement of intervention models.
Characterization of Somatosensory Processing in Relation to Schizotypal Traits in a Sample of Nonclinical Young Adults
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A core feature of schizophrenia spectrum disorders (SSDs) is a basic sensory (e.g., visual, auditory) processing disruption, yet few studies have examined somatosensation. The current dissertation project examined somatosensory processes among individuals at varying degrees of psychometric risk for psychosis using tactile texture and spatial discrimination and letter recognition tasks. Differential patterns of associations of somatosensory abilities with schizotypal trait dimensions (positive, negative, disorganized), independent of anxiety and depressive symptoms, and the relative contributions of bottom-up (peripheral and morphologic features) versus top-down (error types) processing were examined. It was hypothesized that: 1) performance on somatosensory tasks would account for significant variability in total schizotypal traits; 2) somatosensory performances would be differentially associated with schizotypal trait dimensions, and somatosensory performances would account for variability in schizotypal traits beyond mood symptoms; and, 3) central and peripheral mechanisms may contribute to somatosensory performance, but they were not expected to fully account for the associations between basic somatosensory processing and schizotypal traits. Participants were 125 (37 Male/88 Female) young adults (Mage = 20.55, SD = 3.27) recruited from the City University of New York human subjects pool. Participants were asked to complete somatosensory tasks and mood and personality self-report measures. Fingerprints were obtained to assess morphologic features. Anxiety and depressive symptoms were included as covariates, as they accounted for a significant proportion of variability schizotypal traits. Contrary to hypotheses, after accounting for the relative contributions of mood symptoms, better spatial discrimination and rough texture discrimination abilities were associated with more disorganized and negative schizotypal traits, respectively, at the trend level. Exploratory analyses demonstrated some differential contributions of dermatoglyphic features and letter recognition confusion errors in accounting for variability in schizotypal traits. Specifically, more isomorphic errors were significantly associated with fewer negative (and total) schizotypal traits, and, at trend level, more minutiae were associated with more positive schizotypal traits. Findings are discussed in the context of theories regarding neural substrates of somatosensory processing disruptions in SSDs. Implications for understanding SSD etiology and using somatosensory measures as possible indicators of risk for psychosis are posited.
THE EFFECTS OF CHILDHOOD MALTREATMENT ON CRIMINAL AND SUBSTANCE ABUSE OUTCOMES IN URBAN YOUTH DIAGNOSED WITH ADHD
Virginia De Sanctis
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Results from longitudinal studies of individuals diagnosed with attention-deficit/hyperactive disorder (ADHD) in childhood have clearly shown that these children are at heightened risk for poor outcomes as they enter into adolescence and early adulthood. Among poor outcomes criminality (Barkley, Fischer, Edelbrock, & Smallish, 1990; Hechtman & Weiss, 1986; Mannuzza, Klein, Konig, & Giampino, 1989; Mannuzza, Klein, Bessler, Malloy, & LaPadula, 1993) and substance use disorders (SUDs; Mannuzza, Klein, Bessler, Malloy, & LaPadula, 1998; Wilens, Biederman, & Mick, 1998; King, Iacono, & Mcgue, 2004) are particularly prevalent and cause significant hardship for the individual, their family, and society at large. While early conduct disorder (CD) has been shown to account for a substantial portion of the risk associated with later criminality and substance use in youth with ADHD (Armstrong & Costello, 2002; Brook, Whiteman, Cohen, Shapiro, & Balka, 1995; Disney, Elkins, Mcgue, & Iacono, 1999; Barkley, Fischer, Smallish, & Fletcher, 2004), the extent to which other factors, such as a history of childhood maltreatment, contribute to poor outcomes remain relatively unexplored. This is surprising given the fact that 1) there is a clear literature showing that childhood maltreatment confers considerable risk for later poor outcome in general population studies (Cicchetti & Manly, 2001; Widom, 1989a; Smith & Thornberry, 1995; Zingraff, Leiter, Myers, & Johnsen, 1993; Ireland, Smith, & Thornberry, 2002; Smith, Ireland, & Thornberry, 2005), and 2) children diagnosed with ADHD are at increased risk for maltreatment due to externalizing behaviors and dysfunctional parental relations (Briscoe-Smith & Hinshaw, 2006; Ford, Racusin, Daviss, Ellis,Thomas, Rogers, et al., 1999). To our knowledge, no study has examined the contributory role of childhood maltreatment on later poor outcome among children with ADHD. The identification of maltreatment as risk factor is important as it could 1) significantly change the way clinicians assess and treat children with ADHD, and 2) be instrumental in the development of more targeted treatment alternatives and interventions for this at risk population. The following series of studies investigated the role of childhood maltreatment in the development of later criminality and SUDs in adolescents and young adults in a referred sample of urban, ethnically and socio-economically diverse children recruited in childhood between the ages of seven and 11 years and diagnosed with ADHD (N = 183). This group was re-assessed in adolescence (n = 98), almost ten years later, and compared to a well-matched, never-ADHD comparison group (n = 85). Official criminal records for the sample were obtained approximately three years after commencement of the adolescent follow-up. The results of these studies clearly establish a history of childhood maltreatment as a potent and important risk factor for later poor outcome in ADHD youth. In addition, it appears from our results that at least some portion of the poor outcome that has been attributed to CD in ADHD studies may in fact be due to childhood maltreatment. These findings have important implications with regard to antisocial and substance use outcomes and emphasize the utility of assessing childhood maltreatment in ADHD populations.
Emotion Regulation and Aging: A Neurophysiological Study
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Cognitive emotion regulation (ER) pertains to the ability to change the way we attend to and experience emotional information and events. Older and younger adults, however, differ in the way that they attend to emotional information. Socioemotional Selective Theory (SST) suggests that as we age we become more adept at using cognitive ER strategies to reduce negative emotion because we have less time left in life. As a result of these motivational changes, a branch of SST, the positivity effect, proposes older versus younger adults attend to and remember more pleasant than unpleasant stimuli. Research that systematically examines different types of cognitive ER in controlled (reappraisal) and automatic (directed attention) contexts, using neurophysiological measures, has the potential to clarify the nature of the positivity effect. The present research capitalizes on the excellent temporal resolution of the late positive potential (LPP) which is sensitive to attention to emotion and the use of cognitive ER strategies: increasing emotional responses produces larger LPP amplitudes and decreasing smaller LPP amplitudes. Chapter one served to first evaluate whether cognitive ER impacts memory performance and if the LPP during a cognitive ER task was associated with memory performance in younger adults (N = 49). Subsequent research presented uses the LPP to understand whether younger (n = 49) and older adults (n =28) differ in: a) how they attend to emotional information during a passive viewing task (bottom-up); b) how they use two types of cognitive ER strategies, reappraisal (top-down) and directed attention (intermediary top-down); c) how cognitive ER strategies impact memory performance. Results highlight several important contributions to the cognitive ER and aging literature. First, in the initial study results showed that instructions to increase emotional responses to unpleasant stimuli results in larger LPP amplitudes as compared to viewing or decreasing emotional responses. Memory performance in the increase and view conditions was better than the decrease condition. Additionally, larger LPP amplitudes in the increase and decrease conditions were associated with better memory performance. Second, older adults showed sustained attention to emotional stimuli; however younger and older adults did not show preferential attention to unpleasant and pleasant stimuli (respectively). Third, younger and older adults did not differ in their ability to use reappraisal as measured via the LPP, but did show differences in LPP amplitudes on the directed attention task to unpleasant stimuli. Younger, but not older adults showed larger LPP amplitudes to unpleasant stimuli presented with an arousing versus non-arousing focus. Fourth, age differences in memory performance did not emerge; however stimuli presented with an arousing focus were remembered more than those with a non-arousing focus. Fifth, only larger LPP amplitudes to unpleasant stimuli in the decrease condition (relative to a neutral maintain) were associated with better memory performance for younger and older adults. Taken together results suggest that older versus younger adults may sustain processing of emotional stimuli and that age differences in cognitive ER may lie within bottom-up cognitive ER tasks as opposed to reappraisal. Results hold promise that the LPP may be a useful tool for examining other types of cognitive ER strategies in younger and older adults.
Roles of dopamine D1 and D2, opioid and glutamate NMDA receptor signaling in the acquisition and expression of fat- and glucose-conditioned flavor preferences in rats and c-Fos analysis of the dopamine mesotelencephalic and nigrostriatal pathways following intake of sugars and fats in rats.
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Systemic administration of the non-competitive NMDA antagonist, MK-801, demonstrated that acquisition, but not expression, were found to affect the orosensory-mediated (flavor/flavor: f/f) fructose-conditioned flavor preference (CFP). The present studies demonstrated a similar outcome when f/f and f/n processes were combined. Fat-CFP and glucose-CFP studies indicated that systemic injections of the NMDA antagonist, MK-801, were able to significantly reduce acquisition, but not expression, of Corn-Oil (CO)-CFP and glucose-CFP. Both studies appear to have mitigated effects on acquisition as compared to the separate orosensory and postingestive CFP studies. Previous studies found that systemic administration of dopamine (DA) D1 (SCH23390) and D2 (raclopride) antagonists blocked both the acquisition and expression of the orosensory-mediated fructose-CFP and sham sucrose-CFP. DA D1, but not D2, blocked the f/n acquisition, and to a lesser degree, expression, of IG sucrose-CFP. The current study of both fat-CFP and glucose-CFP found that DA D1 and D2 antagonists did attenuate the acquisition and expression of conditioned flavor preference of CO-CFP and oral glucose-CFP, but to a lesser degree. Similar to how a combined f/f and f/n solution is affected by an NMDA antagonist, DA D1 and D2 antagonists do affect the combined f/f and f/n solutions of CO and glucose, but not to the degree observed for fructose-CFP or IG glucose-CFP. It is suspected that certain areas of the mesotelencephalic and nigrostriatal DA pathways affect CFP, such as the nucleus accumbens (NAc), the amygdala (AMY), the medial prefrontal cortex (mPFC), or the dorsal striatum (caudate and putamen: CPu). The present study examined the origin of DA (ventral tegmental area: VTA) and the five projection zones (NAc shell, NAc core, AMY, mPFc and CPu) simultaneously for fos-like immunoreactivity (FLI) following oral ingestion of CO (f/f and f/n), glucose (f/f and f/n), fructose (f/f) and three controls (water, saccharin and xanthan gum). CO, which was isocaloric to fructose and glucose, elicited significantly higher FLI in the NAc core, the AMY, the mPFC, the VTA and the CPu than the controls. Glucose elicited significantly higher FLI in the AMY, the CPu and the NAc core than the controls. Fructose elicited significantly higher FLI in the AMY and the CPu than the controls.
Couple Communication, Attachment Status and Relationship Satisfaction.
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Researchers have been working to understand how relationships begin, what makes them last, what the ingredients are for a satisfying relationship, and what predicts their dissolution. Adult attachment has been found to be associated with the formation, satisfaction, maintenance of, and communication within romantic relationships. The present study explores the associations among adult attachment, communication, and marital and premarital satisfaction. Most studies rely on an individual's self-report of his or her intimate relationship, while few base their conclusions on observations of relationship interaction. This study looks at specific, audiotaped, interactions between couples as well as self-reports of attachment style, communication style, and relationship satisfaction. There were a number of significant findings that indicate a relationship between couple communication, relationship satisfaction, and attachment status. In addition, there were replications of previous findings on couple communication, couple attachment, and relationship satisfaction. The majority of hypotheses were supported: relationship satisfaction was significantly linked to attachment status, positive aspects of communication were linked to women's attachment status, men's use of Support Validation was significantly related to their partners' attachment status, couple communication and relationship satisfaction were significantly related, and relationship satisfaction (specifically problem intensity) was significantly associated with couple communication. The present study evidences a connection between couples' intrapsychic attachment representations (as measured by self-reports) and their interpersonal relationship communication behavior (as observed using the IDCS). It makes a major contribution to the couple attachment literature by linking the intrapsychic sphere of attachment to the interpersonal sphere of communication behavior.
Striving for Integration: Referential Activity and Object Relational Level in a Sample of Bisexual Women
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Sexuality has been theorized as a particular human experience that is driven, unmirrored in development, and enigmatic, not reaching what Fonagy describes as "second order representation." Yet, as a social being, one is expected to declare and publically live out a sexual identity. This study is situated within this point of contact between the visceral and the sociolinguistic, with particular attention paid to the experiences of bisexual women, whose potential challenges in articulating a sexual identity are considered. The study sample was comprised of forty bisexual women participating in the Dually Attracted Women's Narratives study (Levy-Warren, 2013) returning for the second phase of this longitudinal study (Caflisch, 2013). This work examined how the level of participants' internal object representations was related to language use as they spoke about their sexual identities. The first concept was operationalized by applying the Differentiation and Relatedness (DR) scale to the Object Relations Inventory. The language measures applied were those of Wilma Bucci's Discourse Attributes Analysis Program, which measures several linguistic characteristics, including the degrees of both emotional immersion (Referential Activity) and reflection in language. The results showed that a less integrated object representational world was associated with more vivid and immersive language. Higher levels of reflective language were found to be associated with more complex object representations. Explanations drawn from theory and empirical work are offered, focusing on the cognitive and regulatory role of more complex object representations. An analysis of interviews selected based on patterns of these empirical measures confirmed different language styles between those with relatively high and low object relational levels. These results could indicate different defensive processes being employed at different levels of object representation when discussing sexual identity. A qualitative examination of all forty interviews revealed a theme that was examined in depth, namely, how women represented gender, and how these representations might be related to the degree of integration of their object representations. The study provided some confirmation of psychoanalytic understandings of the role of internal object representations and the unique qualities of sexuality as a force. Clinical and theoretical implications regarding bisexual women are also discussed based on the quantitative and qualitative findings.
An Analysis of Social Referencing Stimulus Classes Among Children with Autism
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Social referencing consists of a child looking to the affective responses of an adult, which serve as discriminative stimuli for subsequent responding in the context of ambiguity or novelty. In this study, social referencing was defined as discriminative responding under a two-link chain. The discriminative stimulus for the first link was the presentation of experimental stimuli in the presence of which an observing response was required. Link 2 consisted of a conditional discrimination. The discriminative stimulus for the second link was an affective stimulus from one of two sets presented by the experimenter. Two experiments were conducted to teach children with autism to respond differentially to affective stimuli within the social referencing response chain, and to determine if differential responding generalized to similar stimuli. Experiment 1 attempted to evaluate discriminative responding to two sets of six affective stimuli in Link 2 of social referencing while participants encountered stimuli representing three types of tasks pictured in their activity schedules (i.e., handwriting, retrieving objects, and scripted social interaction). Because discriminative responding was not acquired by any of the three participants under that training paradigm, Experiment 2 was conducted. During this experiment, participants were seated at desks and were presented with stimuli that signaled social referencing. One affective stimulus from each of the two sets was used as the training stimulus. The remaining affective stimuli from the two sets were presented as probe stimuli to determine the extent to which each was part of an already established stimulus class. Participants were taught to engage in differential responding using manual guidance, differential reinforcement, and error correction. In the presence of an affective display from set 1 (e.g., smiling and nodding head), the correct response was a keep response in which the participants placed the stimuli in a bin on the desk. In the presence of an affective display from set 2 (e.g., shake head with eyebrows turned down), the correct response was a discard response in which the participants placed the stimuli in a garbage bin on the floor. Correct responding on training trials increased above baseline levels for all three participants with the systematic introduction of conditional discrimination training. Probe responding was inconsistent across the three participants, obviating analysis of stimulus class formation.
Sex Differences in Progestational Effects on Cocaine-induced Behaviors and Neural Plasticity
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Both clinical and rodent models have shown sexually dimorphic patterns in all phases of drug use and addiction (acquisition, maintenance and relapse). These sexually dimorphic responses to psychostimulants are hypothesized to be due to ovarian hormones. Progesterone has been reported to attenuate many of the behaviors associated with cocaine, in females. Progesterone inhibited cocaine-induced locomotor responses in intact male and female rats. Although progesterone attenuated cocaine-induced behavioral responses, it failed to alter cocaine-induced neural plasticity. Progesterone increased dendritic spine densities in the shell and core of the Nucleus Accumbens (NAcS, NAcC) of male rats. Chronic cocaine increased dendritic spines in NAcC, NacS, CA1 region of the hippocampus. In our third experiment, administration of progesterone and finastesteride, an Allopregnalone antagonist, inhibited the expression of cocaine-induced CPP in female but not male rats. In conclusion, progesterone reduces cocaine-induced locomotor activity and learned associations in rats, without reducing neural plasticity.