2024-03-29T06:51:39Zhttps://ir.vanderbilt.edu/oai/requestoai:ir.vanderbilt.edu:1803/47242020-04-22T06:54:09Zcom_1803_205com_1803_66col_1803_206
2011-02-06T21:25:35Z
urn:hdl:1803/4724
Neurocognitive Effects of Treatment of Pediatric Acute Lymphocytic Leukemia: A Neuroimaging Analysis
Livesay, Kate
Acute Lymphocytic Leukemia (ALL) is the most prevalent form of cancer diagnosed in children. The current survival rate is approximately 85% and has been rising over the last two decades. The standard treatment regimen involves intrathecal chemotherapy in addition to corticosteroid drugs. Intrathecal chemotherapy has been shown to cause neurocognitive effects in executive function and IQ. The current study investigates differences in brain activation patterns that could account for the differences in neurocognitive function observed between ALL survivors and healthy controls. In this study, neurocognitive function of ALL survivors was assessed using a test battery that consisted of the Wechsler Intelligence Test for Children-Fourth Edition (WISC-IV) and the Delis-Kaplan Executive Function System (D-KEFS). ALL survivors showed significant deficits on these tests compared to matched, healthy controls. Survivors demonstrating the poorest performance on this battery participated in the neuroimaging component of the study in which brain activation during an inhibitory control task, the Simon task, was measured using functional magnetic resonance imaging (fMRI). ALL survivors demonstrated a compensatory mechanism of cortical recruitment during the Simon task, while performing worse than their matched, healthy controls. There was a significant difference in activation between survivors and healthy controls in the anterior cingulate cortex (BA 24), as predicted, although no differences were found between groups in the prefrontal cortex.
2011-02-06T21:25:35Z
2011-02-06T21:25:35Z
2008-04-04
Thesis
http://hdl.handle.net/1803/4724
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/8272020-04-22T06:55:51Zcom_1803_205com_1803_66col_1803_206
2008-05-26T16:54:46Z
urn:hdl:1803/827
Effect of binocular rivalry suppression on contrast change detection
Hubert-Wallander, Bjorn
Blake, Randolph
Binocular rivalry
Suppression
Contrast
Contrast change
TvC
CRF
Contrast change detection
Contrast sensitivity (Vision)
Thesis performed under the direction of Dr. Randolph Blake of the Dept. of Psychology at Vanderbilt University.
In their 2004 study, Watanabe et al. measure the detectability of contrast increment probes during rivalry dominance and suppression by plotting threshold versus contrast (TvC)functions, finding significant elevation of detection thresholds during suppression. But what about contrast decrements, a probe that actually makes the target image harder to see? Here I review the literature on binocular rivalry and probe studies and measure the effect of two new probe types on detection thresholds. Results show that contrast decrement probes produce a very different pattern of detection thresholds than their increment counterparts. Extrapolating from these results, I also theorize on the effect of suppression on the underlying contrast response function (CRF).
2008-05-26T16:54:46Z
2008-05-26T16:54:46Z
2008-04
Thesis
http://hdl.handle.net/1803/827
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/94412020-04-22T10:27:09Zcom_1803_205com_1803_66col_1803_206
2019-04-23T18:04:04Z
urn:hdl:1803/9441
Analysis of Structural Network Topology in Depression using Graph Theory
Ganesh, Swathi
Neuroimaging studies have suggested a difference in structural brain connectivity in depression. Recently, structural brain connectivity and psychopathology have been studied using graph theory analysis, which provides metrics on properties of brain organization. While there have been some studies applying this analytic technique to study depression, these have largely been done using categorical rather than dimensional approaches to psychopathology. This study applied both a traditional categorical approach and a dimensional approach to examine the relation between commonly used graph theory measures and depression.
The dimensional analysis included 439 subjects and the categorical approach included 357 subjects with depressive symptoms and 82 subjects without any diagnoses. Anatomical co-variance matrices were constructed using 9 morphometric features and matrices were analyzed to produce the following metrics: normalized clustering coefficient, normalized path length, small-world parameter, normalized global efficiency, and normalized local efficiency. The categorical approach utilized an ANCOVA and the dimensional approach utilized multiple regressions. The categorical analysis did not suggest a significant difference between the “depressed” and “healthy” group with regards to any of the graph theory metrics. In the dimensional analysis a significant positive relation was identified between depressive symptom counts and both normalized local efficiency and normalized clustering coefficient. This shows some concordance with previous studies, and suggests that global features of white matter microstructure may be relevant for depression when examined dimensionally. Future studies using other types of neuroimaging data and applying graph theory techniques may yield additional insight into which graph theory metrics are most relevant for depression.
2019-04-23T18:04:04Z
2019-04-23T18:04:04Z
2019
Thesis
http://hdl.handle.net/1803/9441
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/170972022-04-14T21:41:12Zcom_1803_205com_1803_66col_1803_206
2022-04-14T21:41:11Z
urn:hdl:1803/17097
Investigating Brain Networks in Anxious-Misery and Fear Symptom Dimensions
Pines, Julia
Brain network
Local efficiency
Anxiety
Depression
This paper was written in PSY 4999 Honors Thesis class as part of Dr. Antonia Kaczkurkin's Brains Lab.
Anxiety and depressive symptoms can be dissociated into anxious-misery and fear components;
however, little is known about how these two symptom dimensions differ in terms of brain
network properties. Thus, the purpose of this study was to compare the local efficiency of the
default mode network (DMN) and frontoparietal network (FPN) in anxious-misery and fear
symptom dimensions, with examination of six additional networks and small-worldness as
exploratory analyses. To do this, we used data from children ages 9-10 years old from the
Adolescent Brain Cognitive Development (ABCD) Study database. Our primary measure of
interest was local efficiency, which measures the efficiency of information exchange between
nodes of a network when one node is removed. We hypothesized that the DMN would exhibit
increased local efficiency and the FPN would show decreased local efficiency in anxious-misery
symptoms, and both networks would have lower local efficiency in fear symptoms. We found no
significant associations between local efficiency and anxious-misery and fear dimensions or
between small-world omega and the dimensions. However, we found a significant positive
association between anxious-misery symptoms and local efficiency in the FPN and a significant
negative association between fear symptoms and local efficiency in the FPN at uncorrected
levels. These results suggest the need for further study of local efficiency in the FPN in an older
population and the use of other network metrics in anxious-misery and fear symptom
dimensions.
2022-04-14T21:41:11Z
2022-04-14T21:41:11Z
2022-03
Thesis
http://hdl.handle.net/1803/17097
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/50602012-04-02T18:07:59Zcom_1803_205com_1803_66col_1803_206
2012-04-02T18:07:58Z
urn:hdl:1803/5060
Impact of Constraint-Induced Movement Therapy on Brain Function in Children with Cerebral Palsy
Aschner, Amir
Maitre, Nathalie L.
Key, Alexandra F.
Constraint Induced Movement Therapy
Children
Hemiparetic Cerebral Palsy
Examined the effects of Constraint-Induced Movement Therapy on sensory-motor and sensory-perceptual domains as well as speech and language processing. Requirement of PSY 296b - Honors Research, taught by Professor Megan Saylor.
Few studies have examined the effects of Constraint-Induced Movement Therapy (CIMT) in children or its effects beyond sensory-motor domains. Evidence from adult populations suggests that CIMT is linked with cortical restructuring and could have effects on speech, language deficits, and sensory-perceptual processes, domains typically affected by cerebral palsy (CP). Using a five-day camp model, CIMT effects were tested on children age 5-12 with CP using behavioral measures and two event-related potential (ERP) paradigms –speech sound perception and picture-word matching. Data were collected at baseline, immediately after treatment, and 6 months after the camp. We found that paretic limb function improved after CIMT, and ERP waveform patters changed significantly to reflect faster processing and improved organization. These changes persisted at 6 months follow-up.
2012-04-02T18:07:58Z
2012-04-02T18:07:58Z
2012-03-29
Thesis
http://hdl.handle.net/1803/5060
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/94702020-04-22T10:23:41Zcom_1803_205com_1803_66col_1803_206
2019-05-03T18:15:56Z
urn:hdl:1803/9470
Exploring Predictors of Affective State during d-Amphetamine Intake
Kundzicz, Paul
Zald, David
Smith, Christopher
dopamine
affect
psychostimulants
PET
Possible predictors of positive and negative affective response to oral d-Amphetamine were examined in healthy adults using secondary data analysis on two datasets. The predictors examined included subjective response to the drug, midbrain D2/D3 binding potential, and stable personality traits. Using correlational analyses, D2/D3 binding potential and stable personality traits were found to not have significant associations with positive or negative affect. In contrast, subjective response to d-amphetamine was found to be positively associated with negative affect, though this finding did not replicate across datasets. In subsequent multiple regression models, one dataset showed a significant positive relationship between negative affect and the degree to which participants subjectively felt the effects of the drug, while the other dataset showed a significant positive relationship between negative affect and the degree to which participants subjectively disliked the effects of the drug. Though the lack of replication across datasets makes it difficult to draw definitive conclusions, these findings suggest that negative affect may play a major role in people’s experience of drug use.
PSY-4999: Honors Thesis, Amy Booth
2019-05-03T18:15:56Z
2019-05-03T18:15:56Z
2019-04-08
Thesis
http://hdl.handle.net/1803/9470
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/180782023-04-20T11:49:37Zcom_1803_205com_1803_66col_1803_206
2023-04-20T11:49:36Z
urn:hdl:1803/18078
Structural Brain Differences in Individuals with Bipolar Disorder: A Developmental Perspective
Milewski, Amy
Bipolar Disorder
Brain Structure
Subsyndromal Mania
Pediatric Psychopathology
This paper was written in the PSY 4999 Honors Thesis class as part of Dr. Antonia Kaczkurkin's BRAINS Lab.
While the existence of bipolar disorder in early adolescence is becoming more widely accepted, the degree of manifestation in childhood is still unclear. This thesis summarizes findings on neurostructural correlates of adult bipolar disorder compared to more limited research on pediatric bipolar disorder. Then we examined the relationship between mania symptoms and brain structure in a large sample of children. We analyzed data from 10,699 9-to-10-year-old children from the Adolescent Brain Cognitive Development (ABCD) Study. We employed structural equation modeling to examine the associations between subsyndromal mania symptoms and cortical grey matter volume and thickness in 68 regions. After correction for multiple comparisons and controlling for age, sex, race/ethnicity, and scanner model, we found that mania was associated with smaller brain volumes in 54 cortical regions (pfdr-values ≤ .048). However, none of these effects survived sensitivity analyses that accounted for socioeconomic status, medication use, in-scanner motion, or total intracranial volume (pfdr-values ≥ .299). There were no significant associations between mania and cortical thickness in any region (pfdr-values ≥ .249). Prior studies have identified structural differences in individuals with bipolar disorder, which is supported by the current study’s results in children. However, these results do not survive when controlling for additional covariates, possibly due to the young age of the current sample. Future studies should associate subsyndromal mania with cortical volume and thickness longitudinally to refine our understanding of the emergence of structural changes during the prodromal stage, which could be leveraged for improved identification and intervention.
2023-04-20T11:49:36Z
2023-04-20T11:49:36Z
2023-03
Thesis
http://hdl.handle.net/1803/18078
en_US
Vanderbilt University
oai:ir.vanderbilt.edu:1803/88492018-05-15T18:19:35Zcom_1803_205com_1803_66col_1803_206oai:ir.vanderbilt.edu:1803/11112020-04-22T08:26:33Zcom_1803_205com_1803_66col_1803_206
2008-07-28T21:34:52Z
urn:hdl:1803/1111
Effect of striatal and extrastriatal D2-receptor BP on memory and symptoms of schizotypal personality disorder
Patterson, Katherine A.
D2-Receptor BP
Memory
Thesis completed in partial fulfillment of the requirements of the Honors Program in the
Psychological Sciences
Under the direction of David H. Zald
The integrity of particular dopaminergic projections via the striato-thalamiccortical
feedback loop potentially influences specialized aspects of cognition and
psychopathology. Research has identified a role for striatal D2 receptors in the cognitive
impairments and psychopathological symptoms associated with disorders of the
schizophrenia spectrum. Recent developments in PET neuroimaging methods currently
permit visualization of D2/D3 receptors in extrastriatal regions. This study evaluated
potential correlations between the regional D2/D3 receptor BP in striatal and extrastriatal
areas and psychopathological symptoms and memory performance. Significant
correlations were observed between particular regions of D2/D3 receptor BP and both
verbal and visual memory sub-scales of the Wechsler Memory Scale-III.
2008-07-28T21:34:52Z
2008-07-28T21:34:52Z
2007-04
Thesis
http://hdl.handle.net/1803/1111
en_US
Vanderbilt University