Biological Psychology Commons^™

Atypical Morphometry And Connectivity Of The Cortico-Striatal-Thalamo-Cortical Circuit In Children And Adolescents With Chromosome 22q11.2 Deletion Syndrome: A Population At Ultra-High Risk For Developing Obsessive-Compulsive And Schizophrenia Spectrum Disorders, Amanda I. Rowan

LSU New Orleans Theses and Dissertations

Chromosome 22q11.2 deletion syndrome (22q11.2DS) is a complex neurodevelopmental disorder associated with serious medical, cognitive, and psychiatric conditions, including significantly elevated risk for obsessive-compulsive (OCD) and/or schizophrenia spectrum disorders (SCZ). The cortico-striato-thalamo-cortical (CSTC) neural circuit is critical for cognitive and emotional processing. Dysfunction of the CSTC circuit is implicated in the etiopathology of both OCD and SCZ but has not been specifically examined in individuals with 22q11.2DS. This study used structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI), along with standardized psychological and cognitive measures, to investigate atypical morphometry and white matter connectivity within CSTC-related brain regions in …

Exploring Auditory Thalamocortical Pathways In Autism Spectrum Disorder, Caitlin Dyer

LSU New Orleans Theses and Dissertations

Thalamocortical tracts related to language have rarely been examined in autism spectrum disorder (ASD). We examined the medial geniculate nucleus (MGN), Heschl’s gyrus (HG), and planum temporale (PT) volumes, and the connections from MGN to HG and MGN to PT, using MRIs from 39 children with ASD (20 with receptive language impairment, 19 without) and 20 typically developing controls, aged 5-17 years. In children with ASD without language impairment, MGN volume was positively correlated with receptive language scores. Additionally, the thalamus was smaller in children with ASD with language impairment, correlating negatively with receptive language scores in this group. Left …

Working Memory And Language Associations In Children With Autism Spectrum Disorder, Megan A. Goldfarb

LSU New Orleans Theses and Dissertations

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social communication and interaction, with repetitive behaviors or specialized interests. A range of language abilities is seen in ASD, with some having typical abilities and others severe impairments. Working memory (WM) deficits have also been found in some children with ASD. In typically developing, as well as non-ASD children with language deficits a strong relationship has been found between WM and language abilities. Although both language and WM deficits are often seen in ASD, the relationship between these deficits has been underexplored. The objective of this study is …

Early-Life Acetaminophen Exposure Alters Sex-Specific Social And Mate Preference Behaviors In Adolescent And Adult Rats, Anna G. Warner

LSU New Orleans Theses and Dissertations

Epidemiological studies reported associations between early-life exposure Acetaminophen (APAP) exposure and increased risk of Autism Spectrum Disorder (ASD). Rodent studies parallel epidemiological reports, with APAP-exposed animals showing more abnormal social and increased repetitive behaviors. However, mechanisms underlying sex-specific behavioral responses to APAP remain unclear. Here, a rat model was developed to examine possible interactions between APAP and early-life hormonal milieus during the neonatal period of brain sexual differentiation. Subcutaneous (s.c.) injections of either 17�-Estradiol (E2; masculinized) or Letrozole (LTZ; feminized) were administered from Postnatal Days (PD) 1-11 followed by either APAP or saline 45 min after the first injection on …

Atypical Structural Neuroconnectivity Associated With Emotional Face Processing And Clinical Affect In Children With Chromosome 22q11.2 Deletion Syndrome, David Dodd Stephenson Jr

LSU New Orleans Theses and Dissertations

Schizophrenia spectrum disorder (SCZ) is a debilitating psychiatric disorder that affects approximately 1% of the general population. The etiopathology of this disorder is not fully understood with genetic and environmental factors underpinning vulnerability and disease progression. Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) are at ultra-high risk for developing SCZ with 30% developing the disorder in adolescence or young adulthood. To investigate associations with psychosis vulnerability, much work has been performed looking at neurological underpinnings between schizophrenia and 22q11.2DS to assess similarities between both genetic and idiopathic forms of schizophrenia in adults. However, many past studies have assessed this using …

Working Memory Deficits Are Associated With Altered Regional Brain Volume And Structural Connectivity In Children With Chromosome 22q11.2 Deletion Syndrome., Diana Hobbs

LSU New Orleans Theses and Dissertations

Background: Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) exhibit nonverbal learning disability that may manifest in part because of working memory (WM) deficits. 22q11.2DS is a complex developmental disorder with serious physical, learning, cognitive, and psychiatric symptoms including a risk of developing schizophrenia 30 times that of the general population. WM impairment likely contributes to and exacerbates learning difficulties, school problems, existing neuropsychological disorders such as attention deficit hyperactivity disorder (ADHD); and a poor WM may be a biological risk marker for future mental illness. WM impairment is established in this population, but less is known about its neurological origins. …

Structural Connectivity And Immunological Correlates Of Emotion Processing In Children With Chromosome 22q11.2 Deletion Syndrome, Ashley F. P. Sanders

LSU New Orleans Theses and Dissertations

Neurological abnormalities are associated with emotion processing deficits seen in children with neurodevelopmental disorders. Research suggests that inflammatory mechanisms can negatively impact brain structure and function and are thought to play a role in these processing atypicalities. Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) exhibit emotion processing impairments and associated neural abnormalities. We investigated the roles of inflammatory factors and structural connectivity in relation to emotion processing deficits in 28 children with 22q11.2DS and 33 typically developing children (M = 11.12 years old; SD = 2.17). Results indicate poorer social skills and significantly lower emotion recognition scores in children …

Parental Stress, Anxiety, And Depression And Child Emotional Intelligence In Children With 22q11.2 Deletion Syndrome, Megan A. Goldfarb

LSU New Orleans Theses and Dissertations

Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) have serious medical, psychological, and behavioral symptoms that are stressful to their parents. Higher general intelligence quotients (IQ) and emotional intelligence (EI) in children could allay parental stress. Self-reported stress, anxiety, and depression were measured in parents of children with 22q11.2DS (n=42) and a healthy control group (n=20) in relation to children’s IQ and EI. Children with 22q1.2DS had lower IQ and EI scores. Parental groups did not differ in their reported stress, anxiety, or depression. Children’s IQ and EI levels did not relate to parental measures of affect even in the 22q11.2DS …

Attentional Sub-Processes Involved With Emotional Eating, Gregory Denke

LSU New Orleans Theses and Dissertations

Emotional eating behavior is characterized by eating a large amount of calorie dense sweet and/or high fat foods in an attempt to control, cope with, or avoid negative emotions. Numerous factors are likely to contribute to emotional eating behavior, including attentional factors, such as rumination and avoidance coping. Rumination based emotional eating (attention focused on negative stimuli while mindlessly eating) is often utilized to improve mood while dwelling on problems. However, for those inclined to escape/avoid troublesome thoughts, another type of emotional-eating pattern may be used. By focusing attention on food, emotional eating is believed to distract individuals from negative …

Possible Breakdown Of Dopamine Receptor Synergism In A Mouse Model Of Huntington's Disease, Samantha F. Kennedy

LSU New Orleans Theses and Dissertations

The model of basal ganglia function proposed by Albin, Young and Penney (1989) describes two anatomically independent motor pathways, the direct and indirect. However, under normal conditions striatal dopamine (DA) is required for the expression of motor behavior, and DAergic control of the two pathways (via D1 and D2 receptors, respectively) is dependent on co-activation. We tested for a possible breakdown of D1/D2 synergism using transgenic R6/1 mice bearing the human huntingtin allele (Htt). Motor stereotypy, observed prior to the onset of HD-related symptoms, was rated on a 5-point scale following activation of: A) D1 receptors alone, B) D2 receptors …

Neurocorrelates Of The Mirror Neuron System In Children With Chromosome 22q11.2 Deletion Syndrome, Ade Marais

LSU New Orleans Theses and Dissertations

Activation of brain regions that make up the mirror neuron system (MNS) is thought to reflect processing and perceiving behavior, action, and intentionality of other organisms. Sensing and perceiving motor behavior in others is an important component of understanding and participating in social interactions. Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) are diagnosed with serious medical, cognitive, and socio-emotional symptoms. Atypical development and function of the MNS may underpin some aspects of socio-emotional impairment and autism spectrum disorder (ASD)-like symptomology reported. This study of the MNS investigates differences in activation in the operculum, sensorimotor areas, and basal ganglia (BG) in …

If It Feels Good, View It: Selective Exposure And Desensitization Moderate The Association Between Video Gameplay And Pleasure-Oriented Aggression, Mejdy M. Jabr

LSU New Orleans Theses and Dissertations

A number of studies have indicated that violent video gameplay is associated with higher levels of aggression, and desensitization to violent content contributes to this association. Utilizing a rapid serial visual presentation (RSVP) task, the current study used event-related potentials (ERPs) to investigate selective attention (N1 activation), cognitive control (N2 activation), and desensitization (P3 activation) as neurocognitive mechanisms potentially underlying the association between gameplay and subtypes of aggression. Results showed video game players and non-players differed significantly in brain activation when engaged with violent imagery. N1 and P3 amplitude moderated the association between gameplay and pleasure-oriented aggression. Follow-up analyses further …

Neural Mechanisms Of Action Switching Moderate The Relationship Between Effortful Control And Aggression, Eric L. Rawls

LSU New Orleans Theses and Dissertations

Aggression and violence are social behaviors that exact a significant toll on human societies. Individuals with aggressive tendencies display deficits in effortful control, particularly in affectively charged situations. However, not all individuals with poor effortful control are aggressive. This study uses event-related potentials (ERPs) to decompose the chronology of cognitive functions underlying the link between effortful control and aggression. Specifically, this study investigates which ERPs moderate the effortful control - aggression association. We examined three successive ERP components (P2, N2 and P3) for stimuli that required effortful control. Results indicated that N2 activation, but not P2 or P3 activation, moderated …

Working Memory Impairments In Chromosome 22q11.2 Deletion Syndrome: The Roles Of Anxiety And Stress Physiology, Ashley F. P. Sanders

LSU New Orleans Theses and Dissertations

Stress and anxiety negatively impact the working memory system by competing for executive resources. Broad memory deficits have been reported in individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS). We investigated anxiety and physiological stress reactivity in relation to visuospatial working memory impairments in 20 children with 22q11.2DS and 32 typically developing children (M = 11.10 years, SD = 2.95). Results indicate reduced post-stress RSA recovery and overall increased levels of cortisol in children with 22q11.2DS. Additionally, anxiety mediated the relationship between 22q11.2DS and visuospatial working memory impairment. However, there was no indication that stress response physiology mediated this association. …

Hormonal Correlates Of P50 Suppression In Socially Anxious Young Adults, Andrea M. Tountas

LSU New Orleans Theses and Dissertations

Ten to 15% of the population is temperamentally shy and have elevated physiological stress responses to novel social situations. Yet, the neural mechanisms underlying this personality trait are not fully understood (Beaton et al., 2009; Schmidt et al., 1997). Efficiently attending to, acting on, and remembering relevant stimuli and filtering out less important information is critical given the sheer volume of sensory and perceptual stimuli the brain is exposed to.

Relevant stimuli that garner attention are remembered and consolidated with existing memories. Stimuli that do not warrant extended attention are ignored or habituated to in a process underpinned by cortical …

Effects Of Pharmacological De-Prenylation Of Rhes On Motor Behavior In A Beta-Nitropropionic Acid Animal Model Of Huntington's Disease, Ashley Whitmarsh

LSU New Orleans Theses and Dissertations

Huntington’s disease (HD) is a heritable, neurodegenerative disorder characterized by motor, cognitive, and psychiatric disturbances. The progressive disease is caused by an unstable CAG expansion within the gene that normally encodes for the huntingtin protein (Htt). The expanded mutant form of Htt (mHtt) is expressed ubiquitously throughout patients’ bodies; however, neuronal degeneration is prominent only in the corpus striatum and, to a lesser extent, the cortex. The Ras homolog Rhes is also preferentially localized to the striatum. The putative co-factor Rhes has been shown to act with mHtt to cause neuronal death. Simvastatin, a lipid lowering drug, and zoledronate, a …

Emotional And Autonomic Responding To Auditory Stimuli, Jeremy C. Peres

LSU New Orleans Theses and Dissertations

Much of the research examining emotion induction, regulation, and suppression considers solely the visual modality (e.g., pictures of faces) for emotion elicitation. In reality, emotions are cued, expressed, and interpreted through multiple modalities by employing the extensive use of auditory stimuli in addition to visual stimuli. There have been some recent efforts to offset this imbalance in modality preference by using emotional auditory stimuli alone or in addition to visual stimuli. This project aims to further investigate emotional and autonomic responding to auditory stimuli with the added component of examining differential responding across social (nonlinguistic vocal expression) and non-social auditory …

Parent And Child Vagal Tone: Examining Parenting Behaviors As Moderators Of The Association, Rebecca Graham

LSU New Orleans Theses and Dissertations

Research indicates that learning how to regulate one’s emotions is critical to successful child development and is associated with adaptive social functioning and psychological adjustment (Dunn & Brown, 1994; Eisenberg, Fabes, Guthrie, & Reiser, 2000; Eisenberg, Fabes, & Murphy, 1996). Children’s emotion regulation abilities are thought to be influenced by both child (e.g., age, temperament) and parent characteristics (e.g., parenting behaviors, parental regulation; Eisenberg, Cumberland, & Spinrad, 1998). Resting heart rate variability (HRV) has emerged as a potentially important biomarker associated with emotion regulation (Porges, 2007; Thayer & Lane, 2000); however, there are still significant gaps in research. In particular, …

Effectiveness Of Statin And Bisphosphonate Treatment In A 3np Model Of Huntington’S Disease, Leslie K. Kelley

LSU New Orleans Theses and Dissertations

No abstract provided.

Effects Of Rhes Prenylation On Mouse Cognition In A 3-Nitropropionic Acid Animal Model Of Huntington's Disease, Diana Hobbs

LSU New Orleans Theses and Dissertations

Located on the short arm of chromosome 4, there exists a gene, IT15, responsible for the trinucleotide CAG expansion involved in the autosomal dominant neurodegenerative disorder known as Huntington’s disease (HD). The brain region associated with the most atrophy, the striatum, leads to expression of severe motor dysfunction, the hallmark feature of HD. To a lesser degree, the cortex and hippocampus show earlier deterioration indicative of the cognitive deficits that occur prior to motor symptom onset. The brain regions associated with HD-induced neuronal death additionally selectively express the protein Rhes - the combination of Rhes and mutant huntingtin being cytotoxic. …

The Influence Of Dopamine On The Magnitude And Duration Of The Placebo Effect, Steve T. Brewer

LSU New Orleans Theses and Dissertations

A placebo effect is a real and beneficial psychobiological phenomenon following the administration of a substance or procedure that has no inherent power to produce an effect. Nocebo effects, on the other hand are genuine and detrimental psychobiological phenomenon following the administration of and inert substance or procedure. These effects have been extensively studied but are not well understood. Central to the development of a placebo effect is the anticipation of benefit or the anticipation of harm. Indeed, expectancy and conditioning are thought to be the two primary mechanisms involved in the acquisition of the placebo effect. The neurotransmitter Dopamine …

Testosterone Reactivity And Neural Activation In The Mid Task, Yoojin Lee

LSU New Orleans Theses and Dissertations

The purpose of the project was to determine if testosterone reactivity and neural changes could be observed in response to a reward-seeking competitive task, respectively, and whether testosterone was related to neural activation. Forty nine undergraduate students were recruited playing the Monetary Incentive Delay (MID). We found that a subset of participants (N=20) showed testosterone reactivity to the task (ps < .05). During the EEG analyses, cue had a main effect on FRN amplitude in a trend level (p = .084): The large incentive cue triggered smaller (less negative) FRN amplitude than the small incentive cue did (p < .05), especially during the second reward seeking block (A’) (p = .065) and especially within males (p < .05). Testosterone level and reactivity were not further associated with FRN amplitude (ps > .1). Taken together, results show both testosterone and …

Coupling Of The Hpa And Hpg Axes, Andrew Dismukes

LSU New Orleans Theses and Dissertations

The Hypothalamic-Pituitary-Adrenal (HPA) and –Gonadal (HPG) axes have been considered mutually inhibitory; however, emerging evidence supports the proposition that this might not necessarily be the case. This idea is termed “coupling,” in which the HPA-HPG axis are mutually activated or deactivated. Coupling is examined across three data sets with different time-courses of stress exposure, and results demonstrate HPA-HPG co-activation occurs. Furthermore, stress exposure influences this relationship. The discussion shows how it is physiologically possible to have positive coupling or co-activation between these axes according to complex regulatory feedback systems and overlapping neural structures. Findings are interpreted developmentally, because adolescence may …

The Effects Of Chronic Simvastatin Treatment On The Expression Of Behavioral Symptoms In A Transgenic Mouse Model Of Huntington’S Disease, Ashley Whitmarsh

LSU New Orleans Theses and Dissertations

Huntington’s disease (HD) is a heritable, neurodegenerative disorder characterized by motor, cognitive, and psychiatric disturbances. An unstable CAG expansion within the gene normally encoding for the Huntingtin protein is responsible. The expanded mutant form of Huntingtin and the putative protein co-factor Rhes interact and cause cell death within the striatum. We hypothesized chronic treatment with simvastatin, a cholesterol lowering drug, would disrupt the biosynthetical pathway which gives both Rhes and its target cells binding sites and render Rhes inactive. Healthy and HD mice were treated with simvastatin or a vehicle. Animals’ motor behavior was assessed with three separate tests over …

A Multi-Gene By Environment Perspective Of Adhd Symptomatology In Young Children, Amber L. Allison

LSU New Orleans Theses and Dissertations

Attention deficit hyperactivity disorder (ADHD) is a heritable disorder, which has detrimental effects on childhood development and is associated with maladaptive functioning in adulthood. Despite this, we are far from an understanding of the etiology and possible trajectories of ADHD, possibly due to investigations focusing on the contribution of single genes. In fact, single genes are likely not influential enough to alter behavior, but the additive effect of many genes may predispose an individual toward certain behaviors. Further, environmental input can activate or suppress genetic expression, thereby leading to vast individual differences in both normative behavior and psychopathological illness, including …

Perceived And Actual Emotional Control Among Youth: Are There Differential Relations With Anxiety And Aggression?, Brandon Scott

LSU New Orleans Theses and Dissertations

The perception of and actual ability to control emotional responses during stressful, taxing situations are important to an individual’s well-being. Studies have shown that both low perceived control and a low actual ability for emotional control are related to internalizing and externalizing problems in youth. However, significant gaps in research exist in terms of testing theoretical predictions about how perceived and actual emotional control are associated with anxiety and aggressive behavior problems, particularly among adolescents. The first goal of this study was to examine two objective measures of actual control (i.e., vagal tone and vagal regulation) and their link with …

Autonomic And Behavioral Reactivity To An Acute Laboratory Stressor, Jeremy C. Peres

LSU New Orleans Theses and Dissertations

Stress has been widely shown to directly influence people’s emotional and behavioral processing as well as their underlying biological systems. This project examined physiological and behavioral responses as indicators of stress and coping in the context of a psychosocial stressor in a controlled laboratory setting. We examined the association between indicators of behavioral coping and underlying physiological reactivity within participants while experiencing stress. Participants included 68 emerging adults. Physiological measures include autonomic biomarkers (e.g., heart-rate, skin conductance) at rest and during the stressor while behavioral indicators that were coded include acute verbal and non-verbal actions exhibited by participants during the …

The Effects Of Rhes, A Striatal Specific Protein, On The Expression Of Behavioral And Neuropathological Symptoms In A Transgenic Mouse Model Of Huntington's Disease, Brandon A. Baiamonte

LSU New Orleans Theses and Dissertations

Huntington's disease (HD) is a neuropsychiatric disorder characterized by choreiform movement of the limbs, cognitive disability, psychosis and dementia. It is untreatable, incurable, and ultimately fatal. HD is invariably associated with an abnormally long CAG expansion within the IT15 gene on human chromosome 4. Although the mutant huntingtin protein (mHtt) is ubiquitously expressed in HD patients, cellular degeneration occurs only in neurons within the striatum and cerebral cortex. The Ras homolog Rhes is expressed very selectively in the precise brain areas affected by HD. Recent work using cultured cells suggests that Rhes may be a co-factor with mHtt in cell …

A Multigroup Analysis Of The Psychological Factors That Contribute To Persisting Working Attention Problems In Mild Traumatic Brain Injury And Chronic Pain, Kelly L. Curtis

LSU New Orleans Theses and Dissertations

A significant subset of mild traumatic brain injury (mild TBI) and chronic pain (CP) patients report, and sometimes show objective evidence of, persisting cognitive problems. Despite differences in injury mechanisms, there is considerable overlap in the types of persisting cognitive symptoms that are reported by the two populations. Psychogenic, rather than physiogenic, factors are thought to play an important role in the maintenance of these persisting symptoms. The current investigation examined the contributions somatization, depression, and anxiety had on an objective measure of “working attention.” In order to best elucidate the influences these psychological factors had on attentional performance, only …

Merely Misunderstood: Expressive, Receptive, And Pragmatic Language In Children With Disruptive Behavior Disorders, Monica L. Gremillion

LSU New Orleans Theses and Dissertations

Children with Disruptive Behavior Disorders (DBD), including Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) have poorer language skills compared to typically developing children; however, language as a potential risk factor for DBD has received little empirical attention or evaluation. Receptive, expressive, and pragmatic language skills in preschoolers with DBD were examined. Participants were 82 preschool-age children and their primary caregivers. Primary caregivers completed a semi-structured interview and symptom and language questionnaires. Preschoolers completed measures of receptive and expressive language. Results indicated that preschoolers with DBD were more impaired on receptive, expressive, and pragmatic language compared to non-DBD children. Pragmatic …