Computational Neuroscience Commons^™

Hyperparameter Codependence In Fieldnet: Guidelines For Ann Construction, Seiji Akera

Pitzer Senior Theses

Artificial Neural Networks (ANNs) comprise a non-linear modeling method that is often used to analyze neural data in place of linear models. These networks fall under one of two classifications: pure prediction purposes and improving understanding of the brain through neural interpretability. FieldNet is an ANN designed by Dr. Gautam Agarwal that takes complex valued theta oscillations recorded from implanted multi-electrodes and predicts the rat’s location as it moves throughout a maze. In learning neural features to make this classification, FieldNet appears to reconstruct place fields. The construction of FieldNet has an impact on both the performance and reconstruction capabilities …

Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein

CMC Senior Theses

The majority of seizures are self-limiting. Within a few minutes, the observed neuronal synchrony and deviant dynamics of a tonic-clonic or generalized seizure often terminate. However, a small epilesia partialis continua can occur for years. The mechanisms that regulate subcortical activity of neuronal firing and seizure control are poorly understood. Published studies, however, through PET scans, ketogenic treatments, and in vivo mouse experiments, observe hypermetabolism followed by metabolic suppression. These observations indicate that energy can play a key role in mediating seizure dynamics. In this research, I seek to explore this hypothesis and propose a mathematical framework to model how …

Morphological Changes In Dorsal Root Ganglia Macrophages Associated With Neuropathic Pain Mechanisms Suggest A Novel Target For Chronic Pain Therapy, Emily Kussick

CMC Senior Theses

The present study examined morphological changes in the dorsal root ganglia (DRG) following an innate immune stimulus. The importance of the DRG has increasingly become recognized in pain processing as more than just the home of primary afferent cell bodies. All sensory information passes through the DRG via the primary afferents, and on to the spinal cord. The primary afferents synapse with second-order neurons in the spinal cord that ascend towards the brain, where they transmit the pain signal to the limbic forebrain and/or the somatosensory cortex for processing. The DRG is an interesting niche to study at as it …

Extending Power Series Methods For The Hodgkin-Huxley Equations, Including Sensitive Dependence, James S. Sochacki

CODEE Journal

A neural cell or neuron is the basic building block of the brain and transmits information to other neurons. This paper demonstrates the complicated dynamics of the neuron through a numerical study of the Hodgkin-Huxley differential equations that model the ionic mechanisms of the neuron: slight changes in parameter values and inputted electrical impulses can lead to very different (unexpected) results. The methods and ideas developed for the ordinary differential equations are extended to partial differential equations for Hodgkin-Huxley networks of neurons in one, two and three dimensions.

The Characterization Of Alzheimer’S Disease And The Development Of Early Detection Paradigms: Insights From Nosology, Biomarkers And Machine Learning, Isabel Milano

CMC Senior Theses

Alzheimer’s Disease (AD) is the only condition in the top ten leading causes of death for which we do not have an effective treatment that prevents, slows, or stops its progression. Our ability to design useful interventions relies on (a) increasing our understanding of the pathological process of AD and (b) improving our ability for its early detection. These goals are impeded by our current reliance on the clinical symptoms of AD for its diagnosis. This characterizations of AD often falsely assumes a unified, underlying AD-specific pathology for similar presentations of dementia that leads to inconsistent diagnoses. It also hinges …

Cortical Stimulation Mapping Of Heschl’S Gyrus In The Auditory Cortex For Tinnitus Treatment, Austin Huang

CMC Senior Theses

Tinnitus is the perception of sound in the absence of an actual sound stimulus. Recent developments have shifted the focus to the central nervous system and the neural correlate of tinnitus. Broadly, tinnitus involves cortical map rearrangement, pathological neural synchrony, and increased spontaneous firing rates. Various cortical regions, such as Heschl’s gyrus in the auditory cortex, have been found to be associated with different aspects of tinnitus, such as perception and loudness. I propose a cortical stimulation mapping study of Heschl’s gyrus using a depth and subdural electrode montage to conduct electrocorticography. This study would provide high-resolution data on abnormal …

Toric Ideals, Polytopes, And Convex Neural Codes, Caitlin Lienkaemper

HMC Senior Theses

How does the brain encode the spatial structure of the external world?

A partial answer comes through place cells, hippocampal neurons which

become associated to approximately convex regions of the world known

as their place fields. When an organism is in the place field of some place

cell, that cell will fire at an increased rate. A neural code describes the set

of firing patterns observed in a set of neurons in terms of which subsets

fire together and which do not. If the neurons the code describes are place

cells, then the neural code gives some information about the …

Time Frequency Analysis Of Neural Oscillations In Multi-Attribute Decision-Making, Iris Lieuw

Scripps Senior Theses

In our daily lives, we often make decisions that require the use of self-control, weighing trade-offs between various attributes: for example, selecting a food based on its health rather than its taste. Previous research suggests that re-weighting attributes may rely on selective attention, associated with decreased neural oscillations over posterior brain regions in the alpha (8-12 Hz) frequency range. Here, we utilized the high temporal resolution and whole-brain coverage of electroencephalography (EEG) to test this hypothesis in data collected from hungry human subjects exercising dietary self-control. Prior analysis of this data has found time-locked neural activity associated with each food’s …

Neural Synchrony In The Zebra Finch Brain, Sydney Pia Goings

Scripps Senior Theses

I am interested in discovering the role of field potential oscillations in producing synchrony within the song system of the male zebra finch brain. An important function attributed to neural synchrony is sensorimotor integration. In the production of birdsong, sensorimotor integration is crucial, as auditory feedback is necessary for the maintenance of the song. A cortical-thalamic-cortical feedback loop is thought to play a role in the integration of auditory and motor information for the purpose of producing song. Synchronous activity has been observed between at least two nuclei in this feedback loop, MMAN and HVC. Since low frequency field potential …