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Full-Text Articles in Neuroscience and Neurobiology

Oral Contraceptives And Affective Disorders: Neurobiology And Informed Choice, Sophia Mae Drezner Jan 2023

Oral Contraceptives And Affective Disorders: Neurobiology And Informed Choice, Sophia Mae Drezner

Scripps Senior Theses

Pregnancy prevention and female reproductive freedom have been some of the most contested political issues for decades. Abortion, a fundamental part of women’s healthcare, divides liberals and conservatives on an international scale. The consequences of unintended pregnancy without safe and reliable contraception are widespread, disproportionately impacting women of color, trans and non-binary folks, and poorer communities. The birth control pill is the most common form of oral contraception (OC) globally. Many people with ovaries begin the pill or other hormonal contraceptive (HC) methods as young as 11 years old. Exogenous progesterone and estrogen are known to impact mood, affect, physiology, …


Investigating Neuroanatomical Evolution Through Proliferative Cells In The Astyanax Mexicanus, Sophie Staeger Jan 2023

Investigating Neuroanatomical Evolution Through Proliferative Cells In The Astyanax Mexicanus, Sophie Staeger

Pitzer Senior Theses

The Astyanax mexicanus is a single species of fish that has two very distinct morphs, the cave fish and the surface fish. 200,000 years ago, cave fish ancestors entered the dark and challenging cave environment of Mexico and were forced to adapt in order to survive. Such adaptions include larger fat reserves, more sensitive olfaction, increased neuromasts, and a unique nervous system structure. Yet, other functions regressed, as they lost their eyes and pigmentation. The Duboué lab has established a clear reciprocal relationship between the volume of structures involved in the neuronal adaptations, but the biological mechanisms underlying the development …


Not Coming Home: The Flaws In Skilled Nursing Facilities And Their Contribution To Cyclical Hospitalizations Of Post-Acute Patients, Kate Eisenbraun Jan 2022

Not Coming Home: The Flaws In Skilled Nursing Facilities And Their Contribution To Cyclical Hospitalizations Of Post-Acute Patients, Kate Eisenbraun

Pitzer Senior Theses

This literature review will discuss the experience of patients within the US healthcare system, focusing on skilled nursing facilities (SNFs) and their contribution to cyclical hospitalizations. SNFs differ from nursing homes and other long-term care facilities by providing short-term, post-operational rehabilitation at a cost lower than what is offered at hospitals. Despite their critical role, SNFs often face fundamental issues, such as understaffing, underfunding, and staff burn-out, which result in lower quality patient care. This thesis argues that the issues faced by SNFs are a result of inconsistencies with state and federal staffing regulations, as well as inadequate insurance reimbursements. …


A Composite Review Of The Proposed Molecular Mechanisms And Genetic Components Underlying Parkinson’S Disease, Paige Brodrick Jan 2019

A Composite Review Of The Proposed Molecular Mechanisms And Genetic Components Underlying Parkinson’S Disease, Paige Brodrick

Scripps Senior Theses

Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the progressive death of dopaminergic neurons present in the substantia nigra. The clinical presentation of PD includes tremors, slowed movement (bradykinesia), muscle and limb rigidity, and difficulty with walking and balancing. While many environmental factors can affect the onset and progression of the disease, genetic mutations have a large influence. Of the identified PD-linked genetic mutations, mutations in the leucine-rich repeat kinase 2 (LRRK2) are one of the most common genetic causes of PD. Located in endosomes, LRRK2 has been shown to play a role in the sorting and endocytosis …


Relations Among Maternal And Paternal Behavior And Children's Stress Biology, S.K. Jiaming Lin, Stacey N. Doan, John Milton Jan 2019

Relations Among Maternal And Paternal Behavior And Children's Stress Biology, S.K. Jiaming Lin, Stacey N. Doan, John Milton

Scripps Senior Theses

Parenting behavior has been shown to have a wide range of effects, influencing children’s psychological and biological stress outcomes. Most research focuses on maternal parenting behaviors, with few studies observing the effects of paternal behaviors or the influence of both parents on their children. In this study, the relationship between maternal and paternal parenting behaviors was examined in its association to predict children’s cortisol levels. Cultural differences in parenting styles was also observed. American (N=86) and Chinese (N=97) families participated in the study, with parents reporting their behaviors. Children’s cortisol was collected during a stressor task and correlational analysis was …


A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel Jan 2012

A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel

CMC Senior Theses

The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …


Clustering Neural Spike Trains With Transient Responses, John D. Hunter, Jianhong Wu, John Milton Dec 2008

Clustering Neural Spike Trains With Transient Responses, John D. Hunter, Jianhong Wu, John Milton

WM Keck Science Faculty Papers

The detection of transient responses, i.e. nonstationarities, that arise in a varying and small fraction of the total number of neural spike trains recorded from chronically implanted multielectrode grids becomes increasingly difficult as the number of electrodes grows. This paper presents a novel application of an unsupervised neural network for clustering neural spike trains with transient responses. This network is constructed by incorporating projective clustering into an adaptive resonance type neural network (ART) architecture resulting in a PART neural network. Since comparisons are made between inputs and learned patterns using only a subset of the total number of available dimensions, …


In Situ Muscle Power Differs Without Varying In Vitro Mechanical Properties In Two Insect Leg Muscles Innervated By The Same Motor Neuron, Anna N. Ahn, Kenneth Meijer, Robert J. Full Sep 2006

In Situ Muscle Power Differs Without Varying In Vitro Mechanical Properties In Two Insect Leg Muscles Innervated By The Same Motor Neuron, Anna N. Ahn, Kenneth Meijer, Robert J. Full

All HMC Faculty Publications and Research

The mechanical behavior of muscle during locomotion is often predicted by its anatomy, kinematics, activation pattern and contractile properties. The neuromuscular design of the cockroach leg provides a model system to examine these assumptions, because a single motor neuron innervates two extensor muscles operating at a single joint. Comparisons of the in situ measurements under in vivo running conditions of muscle 178 to a previously examined muscle (179) demonstrate that the same inputs (e.g. neural signal and kinematics) can result in different mechanical outputs. The same neural signal and kinematics, as determined during running, can result in different mechanical functions, …


Human Stick Balancing: Tuning Lèvy Flights To Improve Balance Control, Juan Luis Cabrera, John Milton Sep 2004

Human Stick Balancing: Tuning Lèvy Flights To Improve Balance Control, Juan Luis Cabrera, John Milton

WM Keck Science Faculty Papers

State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lévy flight. The Lévy index, , is approximately 0.9; a value close to optimal for a random search. With increased skill, the index does not change. However, the tails of the Lévy distribution become broader. These observations suggest a Lévy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill …


Synaptic Transformations Underlying Highly Selective Auditory Representations Of Learned Birdsong, Melissa J. Coleman, Richard Mooney Aug 2004

Synaptic Transformations Underlying Highly Selective Auditory Representations Of Learned Birdsong, Melissa J. Coleman, Richard Mooney

WM Keck Science Faculty Papers

Stimulus-specific neuronal responses are a striking characteristic of several sensory systems, although the synaptic mechanisms underlying their generation are not well understood. The songbird nucleus HVC (used here as a proper name) contains projection neurons (PNs) that fire temporally sparse bursts of action potentials to playback of the bird's own song (BOS) but are essentially silent when presented with other acoustical stimuli. To understand how such remarkable stimulus specificity emerges, it is necessary to compare the auditory-evoked responsiveness of the afferents of HVC with synaptic responses in identified HVC neurons. We found that inactivating the interfacial nucleus of the nidopallium …


Synaptic Heterogeneity And Stimulus-Induced Modulation Of Depression In Central Synapses, John D. Hunter, John Milton Aug 2001

Synaptic Heterogeneity And Stimulus-Induced Modulation Of Depression In Central Synapses, John D. Hunter, John Milton

WM Keck Science Faculty Papers

Short-term plasticity is a pervasive feature of synapses. Synapses exhibit many forms of plasticity operating over a range of time scales. We develop an optimization method that allows rapid characterization of synapses with multiple time scales of facilitation and depression. Investigation of paired neurons that are postsynaptic to the same identified interneuron in the buccal ganglion of Aplysia reveals that the responses of the two neurons differ in the magnitude of synaptic depression. Also, for single neurons, prolonged stimulation of the presynaptic neuron causes stimulus-induced increases in the early phase of synaptic depression. These observations can be described by a …


Dynamic Diseases In Neurology And Psychiatry, John Milton, Deborah Black Mar 1995

Dynamic Diseases In Neurology And Psychiatry, John Milton, Deborah Black

WM Keck Science Faculty Papers

Thirty-two (32) periodic diseases of the nervous system are identified in which symptoms and/or signs recur. In 10/32, the recurrence of a symptom complex is one of the defining features of the illness, whereas in 22/32 oscillatory signs occur in the setting of an ongoing nervous system disorder. We discuss the possibility that these disorders may be dynamic diseases.


Functional Consequences Of Compartmentalization Of Synaptic Input, Melissa J. Coleman, Michael P. Nusbaum Nov 1994

Functional Consequences Of Compartmentalization Of Synaptic Input, Melissa J. Coleman, Michael P. Nusbaum

WM Keck Science Faculty Papers

Intra-axonal recordings of stomatogastric nerve axon 1 (SNAX1) indicate that there are synaptic inputs onto the SNAX1 terminals in the stomatogastric ganglion (STG) of the crab Cancer borealis (Nusbaum et al., 1992b). To determine whether this synaptic input only influenced SNAX1 activity within the STG, we identified the SNAX1 soma in the commissural ganglion (CoG). We found that this neuron has a neuropilar arborization in the CoG and also receives synaptic inputs in this ganglion. Based on its soma location, we have renamed this neuron modulatory commissural neuron 1 (MCN1). While intracellular stimulation of MCN1soma and MCN1SNAX has the same …


Complex Motor Dynamics And Control In Multi-Looped Negative Feedback Systems, Anne Beuter, John Milton, Christiane Labrie, Leon Glass Nov 1989

Complex Motor Dynamics And Control In Multi-Looped Negative Feedback Systems, Anne Beuter, John Milton, Christiane Labrie, Leon Glass

WM Keck Science Faculty Papers

Experiments were performed in normal and Parkinsonian subjects who were asked to maintain a constant finger position using time-delayed visual feedback. The finger position showed complex dynamics, with characteristic differences between normal and Parkinosonian subjects. Here we discuss some of the theoretical issues that must be resolved in order to understand the mechanisms that underlie the generation of these complex signals.