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Function And Dissipation In Finite State Automata - From Computing To Intelligence And Back, Natesh Ganesh Oct 2019

Function And Dissipation In Finite State Automata - From Computing To Intelligence And Back, Natesh Ganesh

Doctoral Dissertations

Society has benefited from the technological revolution and the tremendous growth in computing powered by Moore's law. However, we are fast approaching the ultimate physical limits in terms of both device sizes and the associated energy dissipation. It is important to characterize these limits in a physically grounded and implementation-agnostic manner, in order to capture the fundamental energy dissipation costs associated with performing computing operations with classical information in nano-scale quantum systems. It is also necessary to identify and understand the effect of quantum in-distinguishability, noise, and device variability on these dissipation limits. Identifying these parameters is crucial to ...


Acute Estrogen Synthesis And Action In The Auditory Cortex Of Developing Male Zebra Finches (Taeniopygia Guttata), Daniel Vahaba Jul 2019

Acute Estrogen Synthesis And Action In The Auditory Cortex Of Developing Male Zebra Finches (Taeniopygia Guttata), Daniel Vahaba

Doctoral Dissertations

Birdsong, as with human speech, is learned during an age- and experience-dependent sensitive period early in life. Songbirds must first memorize their parents’ song during a sensory phase, then refine their own burgeoning vocalizations to match the auditory memory of their parents’ song during a sensorimotor phase. While the error-correction aspect of the sensorimotor phase of song learning is comparatively well understood, it is largely unknown how auditory memories are formed and how auditory processing may change across development to facilitate song memorization. The songbird caudomedial nidopallium (NCM) is a brain region that encodes complex communication signals like song and ...


Changes In Color Guidance Over The Course Of A Complex Visual Search, Ryan Papargiris Jul 2019

Changes In Color Guidance Over The Course Of A Complex Visual Search, Ryan Papargiris

Masters Theses

When searching for an object, we store a mental representation of the target, which guides our search through the use of attention. The effectiveness of this search guidance varies depending on the task and the relationship between target and distractors. With a better understanding of how search guidance changes over time within a trial, we can better compare the differences between experimental conditions. Eye tracking data from a variety of search tasks were analyzed to determine how color guidance varied over the course of the trial. Color guidance for a given fixation was evaluated based on the distance in color ...


One Year Change In Cognitive Function In Male And Female Common Marmosets (Callithrix Jacchus), Brianna Healey Jul 2019

One Year Change In Cognitive Function In Male And Female Common Marmosets (Callithrix Jacchus), Brianna Healey

Masters Theses

Long term cognitive studies in humans and nonhuman primates such as macaques are difficult because of their long lifespan. The common marmoset (Callithrix jacchus) is a non-human primate who shares with humans many features characteristic of primates, including a complex brain and cognitive function. They also have a short lifespan (~10 years) that makes them a great model in studies of cognitive aging. This study focuses on the rate of decline in cognitive function in male and female marmosets based on performance on reversal learning tasks over 2 years of testing.

We found that marmosets improved their overall performance from ...


Sex, Motivation, And Reversal Learning In The Common Marmoset (Callithrix Jacchus), Alyssa Carlotto Jul 2019

Sex, Motivation, And Reversal Learning In The Common Marmoset (Callithrix Jacchus), Alyssa Carlotto

Masters Theses

This study examined the relationships between motivation and cognitive performance in male and female common marmosets (Callithrix jacchus). This question was driven by prior data from the Lacreuse lab showing a robust female impairment in reversal learning, as assessed by the number of trials needed to acquire a reversal following a simple discrimination between two stimuli. This thesis tested the hypothesis that the female impairment in reversal learning was mediated by deficits in motivation. Two sets of measures were used to test this hypothesis. I evaluated physical effort via testing on the progressive ratio (PR), a test that requires animals ...


Integration Of Robotic Perception, Action, And Memory, Li Yang Ku Oct 2018

Integration Of Robotic Perception, Action, And Memory, Li Yang Ku

Doctoral Dissertations

In the book "On Intelligence", Hawkins states that intelligence should be measured by the capacity to memorize and predict patterns. I further suggest that the ability to predict action consequences based on perception and memory is essential for robots to demonstrate intelligent behaviors in unstructured environments. However, traditional approaches generally represent action and perception separately---as computer vision modules that recognize objects and as planners that execute actions based on labels and poses. I propose here a more integrated approach where action and perception are combined in a memory model, in which a sequence of actions can be planned based on ...


Mapping A Pup-Responsive Pathway From The Medial Preoptic Area To The Ventral Tegmental Area., Matias Andina Oct 2018

Mapping A Pup-Responsive Pathway From The Medial Preoptic Area To The Ventral Tegmental Area., Matias Andina

Masters Theses

Maternal behavior is the complex array of caregiving behaviors females display towards offspring. In rats, the transition to motherhood depends on the action of various hormones, especially estradiol near parturition, which primes the maternal circuitry to respond to pups upon first encounter at parturition with appropriate maternal behavior. Although virgin rats avoid pups, new mothers are highly motivated to interact with pups, and their maternal behavior depends on the functional interaction between the medial preoptic area (mPOA) and the ventral tegmental area (VTA). However, a precise mapping of the VTA-projecting mPOA neurons remains to be elucidated. To determine whether pup-responsive ...


The Neural Correlates Of Stereotype Threat And The Stereotype Inoculation Model In Young Women, Chaia Flegenheimer Jul 2018

The Neural Correlates Of Stereotype Threat And The Stereotype Inoculation Model In Young Women, Chaia Flegenheimer

Doctoral Dissertations

A promising intervention technique for stereotype threat effects is the stereotype inoculation model (SIM), which utilizes in-group role models to counteract stereotype-induced pressures. However, it remains unclear how the SIM may impact neural mechanisms during stereotype threat, including negative feedback bias (increased attention to undesirable feedback). The following three studies aim to examine the behavioral (Study 1) and neural (Study 2) markers of ST in women and how these markers are influenced by the SIM (Study 3). In each study, participants completed a non-traditional math task (the approximate number task). In the first two studies, one group was told the ...


Effort-Related Motivational Dysfunctions: Behavioral And Neurochemical Studies Of The Wistar-Kyoto Rat Model Of Depression, Brendan Abbott Jul 2018

Effort-Related Motivational Dysfunctions: Behavioral And Neurochemical Studies Of The Wistar-Kyoto Rat Model Of Depression, Brendan Abbott

Masters Theses

Depression and related disorders are characterized by motivational dysfunctions, including deficits in behavioral activation and exertion of effort. Animal models of relevance to depression represent a critical starting point in elucidating the neurobiological mechanisms underlying motivational dysfunctions. The present study explored the use of the Wistar-Kyoto (WKY) animal model of depression to examine effort-related functions as measured by voluntary wheel running and performance on a mixed fixed ratio 5/progressive ratio (FR5/PR) operant task. Given the known link between activational aspects of motivation and the mesocorticolimbic dopamine (DA) system, the behavioral effects of d-amphetamine (0.5 and 1.0 ...


Sleep, And Its Relation To Non-Motor Deficits In Patients With Cerebellar Ataxia, Akshata Sonni Mar 2018

Sleep, And Its Relation To Non-Motor Deficits In Patients With Cerebellar Ataxia, Akshata Sonni

Doctoral Dissertations

The cerebellum is a highly connected structure, and its involvement in sleep – which is a dynamic process that is modulated by a complex set of neural systems – can come about through a number of neural pathways. We conducted two studies aimed at furthering our understanding of cerebellar involvement in sleep behavior and physiology, as well as measuring the impact of poor sleep on mood and cognition in patients with cerebellar degeneration. First, by means of an online battery including measures of sleep and neuropsychiatric function, we collected data from 176 patients with cerebellar ataxia. We found strong evidence of poor ...


Assessing The Long-Term Sequelae Of Mild Traumatic Brain Injury, Janna Mantua Mar 2018

Assessing The Long-Term Sequelae Of Mild Traumatic Brain Injury, Janna Mantua

Doctoral Dissertations

A mild traumatic brain injury (mTBI), also known as a concussion, is defined as an injury that results in an alteration of consciousness or mental status. Previous studies have shown mTBI populations experience a number of chronic (> 1 year) symptoms, such as sleep disturbances (e.g., sleep stage alterations), mood alterations (e.g., depressive symptoms), and cognitive alterations (e.g., poor concentration). The three chapters of this dissertation sought to explore these long-term sequelae and the possible interrelations between them. In the first experiment, sleep-dependent memory consolidation of neutral stimuli was probed in a chronic mTBI sample and a control ...


Sex Differences In Estradiol Signaling In The Zebra Finch (Taeniopygia Gutatta) Auditory Cortex, Amanda Krentzel Nov 2017

Sex Differences In Estradiol Signaling In The Zebra Finch (Taeniopygia Gutatta) Auditory Cortex, Amanda Krentzel

Doctoral Dissertations

Although several sex differences have been described in brain structure, function, and development, sex as a biological factor is underrepresented in neuroscience studies. In the mammalian brain, there are sex differences in the mechanism of rapid estradiol actions on neuronal physiology. In the songbird, the brain is a major source of estradiol production, and estradiol rapidly modulates auditory responsiveness through dynamic changes and an unknown receptor mechanism. I set out to determine if there are sex differences in rapid estradiol modulation of auditory cortical activity, as has been shown in other systems. I tested this hypothesis through three aims: 1 ...


The Role Of Sleep On Inhibitory Control In Young Children With Attention-Deficit/Hyperactivity Disorder (Adhd), Amanda Cremone Nov 2017

The Role Of Sleep On Inhibitory Control In Young Children With Attention-Deficit/Hyperactivity Disorder (Adhd), Amanda Cremone

Doctoral Dissertations

Alongside the hallmark symptoms of hyperactivity and inattention, children with attention-deficit/hyperactivity disorder (ADHD) often report having sleep problems. Although sleep deficits are consistently found when evaluated subjectively, impairments in sleep physiology are inconsistent. Compared to typically developing (TD) children, children with ADHD have greater spectral power in the delta (0.5 to 4 Hz) and theta frequency bands (4 to 7 Hz). Moreover, activity in these bands is differentially related to cognitive outcomes in ADHD and TD populations. As such, this dissertation sought to examine relations between sleep physiology and inhibitory control, a primary deficit of ADHD, in young ...


Explicit Learning Of Phonotactic Patterns Disrupts Language Learning, Evan Hare Oct 2017

Explicit Learning Of Phonotactic Patterns Disrupts Language Learning, Evan Hare

Masters Theses

Learning environment has been proposed to be a cause of age of acquisition effects in second language acquisition. Explicit learning in adults is linked to fast initial gains but poorer ultimate attainment whereas implicit learning in children requires more input but leads to greater proficiency in the long run. The current study used ERP measures to determine if explicit learning of a phonotactic pattern interferes with implicit learning of that same pattern in adults. Listeners were told to figure out the pattern of consonants that can go together in a word by listening to 16 CVCV nonsense words in which ...


A Representational-Hierarchical Account: A New Theory Of False Memories, D. Merika Wilson Jul 2017

A Representational-Hierarchical Account: A New Theory Of False Memories, D. Merika Wilson

Masters Theses

Past research has supported a representational-hierarchical theory of memory and perception that extends the ventral visual stream into the medial temporal lobe. In this account, representations are organized in a hierarchical manner, such that structures located further anterior in the brain contain complex representations of whole objects and areas further posterior in the visual cortex contain representations of simple features. When conjunctive representations are compromised, an individual must rely on simple-feature representations to complete mnemonic and perceptual tasks. However, these simple-feature representations are susceptible to feature-level interference, which can cause false recognition of novel objects. The goal of the present ...


The Effects Of Predictability On Stereotypic Behavior In Nonclinical Adult Humans (Homo Sapiens) And Rhesus Macaques (Macaca Mulatta), Amy Ryan Jul 2017

The Effects Of Predictability On Stereotypic Behavior In Nonclinical Adult Humans (Homo Sapiens) And Rhesus Macaques (Macaca Mulatta), Amy Ryan

Doctoral Dissertations

Stereotypies, or repetitive and purposeless behaviors, are observed in both humans and other animals. They have been primarily studied in captive animal and clinical human populations with comparably little research devoted to understanding less severe levels of stereotypies observed in nonclinical populations of adult humans and in most captive animals. As these behaviors are sometimes associated with routine events, I explored the relationship between the predictability of anticipated events and mild stereotypies. I studied this relationship in captive rhesus macaques and a novel comparison group of adult humans from a nonclinical population. I designed two experimental paradigms, a wait paradigm ...


The Neural Correlates Of Emotion Reactivity And Regulation In Young Children With Adhd, Claudia I. Lugo-Candelas Nov 2016

The Neural Correlates Of Emotion Reactivity And Regulation In Young Children With Adhd, Claudia I. Lugo-Candelas

Doctoral Dissertations

Attention-deficit hyperactivity disorder (ADHD) is the most frequently occurring pediatric neurobehavioral disorder. Although emotion reactivity and regulation are frequently impaired in ADHD, few studies have examined these factors in preschool aged children with ADHD, and none have explored the neural correlates of emotion reactivity and regulation in this group though event-related potentials (ERPs). Children aged 4 to 7 with (n = 24) and without (n = 30) ADHD symptoms completed an attention task composed of four blocks: baseline, frustration, suppression, and recovery. In the frustration and suppression blocks, negative affect was induced by false negative feedback. During the suppression block, children were ...


Effects Of Adolescent Alcohol Binge Drinking On Prefrontal Myelin, Wanette M. Vargas-Rodriguez Nov 2016

Effects Of Adolescent Alcohol Binge Drinking On Prefrontal Myelin, Wanette M. Vargas-Rodriguez

Doctoral Dissertations

Alcohol binge drinking is highly prevalent in teenagers and is associated with various harmful health effects and social problems. During adolescence, brain regions such as the prefrontal cortex (PFC) are still undergoing active development, characterized by increases in white matter volume. While the morphological details and the cellular and molecular sequences governing adolescent white matter development are not fully known, it is known that this development process is sensitive and can be disrupted. Although consumption of alcohol in a binge drinking pattern has been linked to lower white matter integrity in humans, it is important to determine if alcohol is ...


Alterations To Maternal Behavior And Brain By Exogenous Estrogen Exposure, Mary Catanese Nov 2016

Alterations To Maternal Behavior And Brain By Exogenous Estrogen Exposure, Mary Catanese

Doctoral Dissertations

Maternal care is critical for the development and long-term success of offspring. Poor maternal care can have profound effects on offspring that can last into adult life. Despite our understanding of the role of endogenous estrogen in maternal behavior, the potential effects of exogenous estrogens (xenoestrogens) on maternal behavior and brain remain poorly understood.

The active synthetic estrogen in contraceptive pills, 17α-ethinyl estradiol (EE2), is widely used as a positive control for estrogenicity in endocrinology and toxicology studies. Another xenoestrogen, bisphenol A (BPA) alters a broad range of physiological processes including neural development and reproduction. Due to public health concerns ...


The Cellular Context Of Estradiol Regulation In The Zebra Finch Auditory Forebrain, Maaya Ikeda Nov 2016

The Cellular Context Of Estradiol Regulation In The Zebra Finch Auditory Forebrain, Maaya Ikeda

Doctoral Dissertations

Estradiol, traditionally known as a hormone that communicates with distant cells in the body, is also synthesized locally in the brain to act as a neuromodulator. Neuromodulators differ from neurotransmitters in that they simultaneously affect a population of neurons and their actions are not limited to the synapse. One of the many effects of estradiol signaling is rapid modulation of auditory processing in response to external stimuli. The enzyme required for estradiol synthesis, aromatase, is highly expressed in the regions that are involved in higher-order processing of sounds in humans and songbirds. Since zebra finches, a type of songbird, are ...


Probiotics As A Treatment For Increased Nighttime Activity In Rhesus Macaques (Macaca Mulatta) Displaying Self-Injurious Behavior, Lauren L. Stanwicks Nov 2016

Probiotics As A Treatment For Increased Nighttime Activity In Rhesus Macaques (Macaca Mulatta) Displaying Self-Injurious Behavior, Lauren L. Stanwicks

Masters Theses

Self-injurious behavior (SIB) is a behavioral pathology seen in a small percentage of humans and non-human primates. In one previous study, macaques with SIB had more sleep disruption than controls, but observations were limited. Two studies were conducted: a baseline study to investigate nighttime activity in rhesus macaques (Macaca mulatta) displaying SIB and controls, and a probiotic study to assess probiotic Bifidobacterium infantis 35624 for high nighttime activity. Subjects were 13 rhesus macaques, 5 with SIB (3 females; 1 SIB). Videocapture of Nighttime Activity (VNRA) was developed to record in complete darkness. IR-receptive webcams were connected to a laptop running ...


Spider Brain Morphology & Behavior, Skye M. Long Jul 2016

Spider Brain Morphology & Behavior, Skye M. Long

Doctoral Dissertations

Spiders are ideal model animals for experimental and comparative studies of behavior, learning and perception. They display many complex behaviors, such as the multimodal mating dances of lycosid spiders, the stealthy hunting strategies of the jumping spider Portia sp., to the labile sociality of theridiids. Spiders also demonstrate a wide range of cognitive capabilities. Spiders perceive their environment using multiple sensory modalities including: chemosensory organs; lyriform and slit-sense organs and specialized hairs that detect vibration and air movement; and up to eight eyes that vary in function, some able to detect polarization and a broad spectrum of light, including ultraviolet ...


Evaluating A Novel Photochemical Tool For Labeling And Tracking Live, Endogenous Calcium-Permeable Ampars, Rosamund Elizabeth Combs-Bachmann Jul 2016

Evaluating A Novel Photochemical Tool For Labeling And Tracking Live, Endogenous Calcium-Permeable Ampars, Rosamund Elizabeth Combs-Bachmann

Masters Theses

The purpose of this research is to advance development of a photochemical tool designed to probe the role of ionotropic glutamate receptor signaling in neurodegenerative processes, and to delve more deeply into the biological processes underlying the role of these receptors in signaling and memory formation. This ligand-targeted nanoprobe was designed and developed in our lab to label endogenous calcium-permeable AMPARs (CP-AMPARs) in live cells with minimal disruption to native receptor activity. Nanoprobe is designed to use naphthyl acetyl spermine (NASPM) as a photocleavable ligand to target and covalently label native CP-AMPARs with a non-perturbing, fluorescent marker that then allows ...


Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu Mar 2016

Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu

Doctoral Dissertations

Corticotropin-releasing factor (CRF) is the major peptide involved in regulating the body’s autonomic, hormonal, and behavioral responses to stress. Cells that produce and release this peptide are widely distributed throughout the brain. This dissertation focuses on a specific population of CRF cells residing in the medial prefrontal cortex (mPFC) that could potentially influence a number of higher order functions through modulation of local circuits. The prefrontal cortex is known to function sub-optimally in patients suffering from various stress-related psychiatric conditions including alcohol use disorder (AUD), and dysregulated CRF signaling may be an underlying mechanism. Surprisingly little is known about ...


The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson Nov 2015

The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson

Masters Theses

The human intruder test (HIT) is a noninvasive tool widely used for assessing anxiety in rhesus macaques (Macaca mulatta). This thesis explores the HIT procedure and applies it to a population of monkeys with a self-injurious behavioral pathology. Individual variation on this test can be used to assess anxiety and temperament. The first experiment of this thesis applied two different procedures of the HIT to 17 monkeys at UMass. Monkeys displayed little response to the intruder, and no significant differences were detected for the two procedures. To determine whether these responses were unique to the UMass monkeys, their behavior was ...


Regulation Of Jak1 And Jak2 Synthesis Through Non-Classical Progestin Receptors, Hillary Adams Nov 2015

Regulation Of Jak1 And Jak2 Synthesis Through Non-Classical Progestin Receptors, Hillary Adams

Masters Theses

The anteroventral periventricular (AVPV) nucleus of the hypothalamus integrates estradiol (E2) and progesterone (P4) feedback signals from the ovaries to stimulate gonadotropin releasing hormone (GnRH) neurons and trigger an ovulatory surge in luteinizing hormone (LH). E2 maintains the daily cyclic LH surge and P4 quickly amplifies the surge and limits it to one day. P4 amplification of the surge and rapid signaling in the AVPV may occur through its non-classical progestin receptors. Previous in vitro studies using a microarray analysis with N42 mouse embryonic hypothalamic neurons suggest that progesterone membrane component 1 (Pgrmc1) regulates genes ...


Behavioral, Neurobiological, And Genetic Analysis Of The Circadian Mutant Duper, Emily Nicole Corbett Manoogian Nov 2015

Behavioral, Neurobiological, And Genetic Analysis Of The Circadian Mutant Duper, Emily Nicole Corbett Manoogian

Doctoral Dissertations

The recently discovered circadian mutant hamster duper has a short period of ~23 hours and exhibits exaggerated phase shifts in response to a 15-min light pulse. To increase the understanding of the duper mutation, I performed behavioral, neurobiological, and genetic experiments. Behavioral studies using photic and non-photic stimuli found that large phase shifts exhibited by duper hamsters are specific to photic cues, but not to phase. Additionally, 2/3 of duper hamsters, but no WTs, displayed transient ultradian wheel-running patterns when transferred from light to dark at CT 18. This suggests that the mutation may weaken coupling among components of ...


Chemical Biology-Based Probes For The Labeling Of Targets On Live Cells, Amanda M. Hussey Nov 2015

Chemical Biology-Based Probes For The Labeling Of Targets On Live Cells, Amanda M. Hussey

Doctoral Dissertations

Proper detection is the key to studying any processes on the cellular scale. Nowhere is this more evident than in the tight space which confines the synaptic cleft. Being able to ascertain the location of receptors on live neurons is fundamental to our understanding of not only how these receptors interact and move inside the cell but also how neurons function. Most detection methods rely on significantly altering the receptor; both tagging with a fluorescent protein or targeting the receptor by a fluorescent reporter in the form of a small molecule causes significant difficulties. These localization techniques often result in ...


Behavioral And Neural Mechanisms Of Impulsive Choice, Jesse Mcclure Nov 2015

Behavioral And Neural Mechanisms Of Impulsive Choice, Jesse Mcclure

Doctoral Dissertations

Impulsive choice is defined as the preference for a small immediate reward over a larger delayed reward. Individual variablity in impulsive choice correlates with many socially relevant behaviors. Although forms of impulsive choice have been studied in both behavioral ecology and psychology, the exchange of knowledge between these fields is just beginning. Drawing from both of these fields will improve our research methods allowing for a more detailed understanding of this complex behavior. Existing tasks to measure impulsive choice conflate the delay and quantity of the reward. To address this, I have drawn from foraging research to establish a method ...


Interactions Between The Hypothalamic-Pituitary-Adrenal (Hpa) Axis, Oxytocin System, And Behavior In Differently Reared Rhesus Monkeys (Macaca Mulatta), Amanda F. Hamel Aug 2015

Interactions Between The Hypothalamic-Pituitary-Adrenal (Hpa) Axis, Oxytocin System, And Behavior In Differently Reared Rhesus Monkeys (Macaca Mulatta), Amanda F. Hamel

Doctoral Dissertations

Adverse experiences that occur during early critical periods of development modify activity of neuroendocrine systems, such as the hypothalamic-pituitary-adrenal (HPA) axis and oxytocin system. This dissertation examines the effects of nursery rearing, an established model of adverse early experiences, on activity of the HPA axis and oxytocin system in infant and adult rhesus macaques (Macaca mulatta). In addition, influence of oxytocin system activity on the HPA axis and behavioral reactivity was examined. In infant monkeys, nursery-rearing was associated with lower HPA axis, yet higher oxytocin system activity, following the acute stress of developmental assessment. Nursery rearing may result in dysregulation ...