Cognitive Neuroscience Commons^™

Inter-Rater Reliablility Of Sharp Wave Ripple Detection In Recently Trained Experts, Orlando Montiel, Gage Pompa, Yader Gomez, Talha Soluoko

Undergraduate Research Symposium Posters

Sharp wave ripples (SWR) are a brain phenomenon that originate in the hippocampus, a region crucial for memory and learning. These events occur during periods of rest or slow-wave sleep and are characterized by fast oscillatory bursts (150-250Hz) and are thought to be important for the brain to consolidate memory. SWR are believed to facilitate the transfer of information from the hippocampus to the cortex, strengthening synaptic connections & enabling long-term memory storage. Accurate detection & assessment of SWRs is essential for advancing how the brain processes and stores information.

This study examines the accuracy/consistency of SWR image selection and …

Association Between Polygenic Scores For Brain Structure And Alzheimer's Disease, Eunjae Lee, Faria Tavacoli, Tingwei Liu, Brittany Diaz Ruiz, Hayley Ho, Alice Lee, Jingchun Chen

Undergraduate Research Symposium Posters

Alzheimer’s disease (AD) is a progressive neurodegenerative condition and the most common type of dementia. Research has shown that volumetric changes in subcortical brain structures, which make up roughly 25% of the brain's total volume and affect many physiological functions. This research project aims to investigate the genetic association between brain structures and AD. GWAS data of eight different brain structures (ICV, accumbens, amygdala, caudate, hippocampus, pallidum, putamen, and thalamus) were used to create polygenic scores (PGSs) in a discovery (cases/controls = 2,651/2,768) and replication dataset (cases/controls = 553/644). We utilized PRSice-2 software to generate PGSs and assess genetic correlations …

An Investigation Of Frequency-Domain Pruning Algorithms For Accelerating Human Activity Recognition Tasks Based On Sensor Data, Jian Su, Haijian Shao, Xing Deng, Yingtao Jiang

Electrical & Computer Engineering Faculty Research

The rapidly advancing Convolutional Neural Networks (CNNs) have brought about a paradigm shift in various computer vision tasks, while also garnering increasing interest and application in sensor-based Human Activity Recognition (HAR) efforts. However, the significant computational demands and memory requirements hinder the practical deployment of deep networks in resource-constrained systems. This paper introduces a novel network pruning method based on the energy spectral density of data in the frequency domain, which reduces the model’s depth and accelerates activity inference. Unlike traditional pruning methods that focus on the spatial domain and the importance of filters, this method converts sensor data, such …

To Be Conscious Or Not To Be, Bjørn Grinde

Animal Sentience

Carolyn Ristau has done a fine job summarizing the work and life of the zoologist Donald Griffin. Most scientists now accept the existence of animal sentience, but identifying which species possess consciousness remains controversial. Griffin defined consciousness as "the subjective state of feeling or thinking about objects and events.” Nonconscious processes are faster and more energy-efficient, however, and often drive behavior. Consciousness probably evolved for complex decision-making, shaped by evolutionary continuity, with feelings as a common currency for evaluating outcomes. Its survival advantage may be limited, and its presence across species varies depending on evolutionary trajectories.

Structural Projections To The Nucleus Accumbens Link To Impulsive Components Of Human Risk Preference, Loreen Tisdall, Kelly H. Macniven, Josiah Leong, Renato Frey, Jörg Rieskamp, Ralph Hertwig, Brian Knutson, Rui Mata

Psychological Science Faculty Publications and Presentations

Functional responses in the Nucleus Accumbens (NAcc) to risk- and reward-related cues can predict real-life risk-taking behavior. Since NAcc activity depends on neurotransmission from connected brain regions, projections to the NAcc may also predict risk preference. To quantify risk preference, we employed latent variables previously derived in a comprehensive, independent study examining the psychometric structure of risk preference, which yielded a general risk preference factor as well as several specific factors, including a factor capturing impulsivity. Informed by previous work, we preregistered a set of hypotheses concerning the association between different risk preference factors and fractional anisotropy (or FA, which …

Neural Correlates Of Socially Rewarding Memories In Posttraumatic Stress Disorder, Kyle P. Blidy

MUSC Theses and Dissertations

Significance. Memory disturbances for emotional content are central to PTSD, yet most research focuses on trauma memories. Recent evidence suggests that enhancing access to positive memories could improve mood, affect regulation, self-esteem, and integration of trauma memories. However, the neurocognitive mechanisms underlying positive memory encoding in PTSD are poorly understood. No study has examined memory for positive social items in PTSD, which is important because PTSD entails social withdrawal and reduced accessibility to positive memory. Additionally, positive memories embedded in a social context have enhanced subjective value and strengthening their accessibility may confer greater benefits to wellbeing compared to non-social …

Memory Modulation: Dominance Of Negative Visual Context Over Neutral Verbal Memory, Stas Kozak, Noa Herz, Maya Tocker, Yair Bar-Haim, Nitzan Censor

Department of Neurology Faculty Papers

Neutral memories can be modulated via intentional memory control paradigms such as directed forgetting. In addition, previous studies have shown that neutral visual memories can be modulated indirectly, via remember and forget instructions towards competing verbal memories. Here we show that direct modulation of neutral verbal memory strength is impaired by negative visual context, and that negative visual context is resistant to indirect memory modulation. Participants were directly instructed to intentionally remember or forget newly encoded neutral verbal information. Importantly, this verbal information was interleaved with embedded negative visual context. Results showed that negative visual context eliminated the well-documented effect …

Behavioral And Neural Evidence For Perceptual Inference Of Position, Sharif Saleki

Dartmouth College Ph.D Dissertations

Extensive neuroscientific research has advanced our knowledge of the mechanisms involved in the detection and recognition of visual stimuli. However, to guide flexible behavior in a changing world, the brain must also construct stable and coherent perceptual representations from retinal images that are often ambiguous. To resolve ambiguities and uncertainties, the visual system combines its input with other sources of information such as context and prior knowledge to infer the most likely interpretation of a scene. Thus, perception is inherently an inferential process that goes beyond simple detection or recognition of stimuli. Although inference has been studied in many areas …

Robust And Generalizable Representations In The Hippocampus, Hung-Tu Chen

Dartmouth College Ph.D Dissertations

An intelligent system must balance generalizing across similar experiences with maintaining the distinctiveness of each experience. This thesis explores how the hippocampus manages this balance through its neural representations to support adaptive behavior. In Chapter 1, I provide an overview of key hippocampal phenomena that contribute to this process, including remapping, splitter signal, and replay. In Chapter 2, I challenge the concept of random remapping by showing that it is possible to predict, better than chance, how a given experience will be encoded in the hippocampus across different subjects. This suggests that encoding of related experiences, which was previously thought …

Resting-State Eeg Microstate Features For Major Depressive Disorder Classification, George M. V. Quinn

Dissertations, Theses, and Capstone Projects

Neuroimaging studies have revealed consistent abnormalities in functional connectivity within specific neural networks that may serve as biomarkers for major depressive disorder (MDD). It is important to find inexpensive, non-invasive techniques that target these biomarkers to make diagnosis easier and more objective. EEG microstates are quasi-stable potential topographies that are thought to reflect the quasi-stable network activity of the underlying neural generators. MDD has been shown to alter features of the four canonical EEG microstates (A, B, C, D) with some conflicting results. The most consistent network abnormalities in MDD are found in the anterior default mode network, and this …

Meconium: A Potential Means To Predicting Later-Life Cognition, Leah Duran

Dissertations, Theses, and Capstone Projects

Maternal perinatal stress is a commonly experienced, yet chronically undiagnosed condition (CDC, 2010). Literature has suggested that perinatal stress exposure has long lasting implications of the developing child both physically and mentally (Behrman et al., 2007; Hobel et al., 2008; Bowman et al., 2004; Polanska et al., 2017; Van de Bergh et. al, 2020). The use of meconium in the clinical setting has become one that serves a purpose of detection in medical conditions like in utero drug exposure. Using meconium as a predictor for brain behavior, however, is still an emerging concept in the literature. It is quickly gaining …

Competitive And Noncompetitive Credit Assignment To Reward Cues In The Lateral Orbitofrontal Cortex, Mihwa Kang

Dissertations, Theses, and Capstone Projects

This dissertation investigates the mechanisms underlying variations in credit assignment to reward cues, with a focus on the lateral orbitofrontal cortex (lOFC). The lOFC has long been implicated in signaling reward expectancies, with controversy as to whether it signals the economic value of future outcomes, their sensory features to guide behavior or both. However, whether the lOFC signals the relative (competition-dependent) or absolute (contiguity-dependent) credit of cues is unknown. To address this, I employed a combination of novel behavioral assays, in-vivo electrophysiological recordings and optogenetic stimulation in rats. In Chapter 2, I tested the suitability of a self-initiating variant of …

The Neuroscience Of Mindfulness Based Art Therapy: A Literature Review, Elizabeth Strasser

Expressive Therapies Capstone Theses

Art therapy and neuroscience are two fields which are currently growing and expanding with the development of new technology which allows for therapists and scientists to advance their understanding of how the brain and the body respond to the world around us. The interaction between the brain, body, and environment is complex, and for the sake of clarity for this thesis this interaction will be conceptualized through the lens of the body-mind model, polyvagal theory, neuroaesthetics, the flow state, mindfulness, sensory engagement, and art as therapy. Neuroscience in relation to psychology can be used to develop a deeper understanding of …

High Fat Diet & Social Isolation: Interactive Effects On Pain, Cognition, & Neuroinflammation, Ian M. Campuzano

Research Psychology Theses

Prior research has established a role for both social isolation and exposure to high fat Western diets in altering a range of behaviors from reduced memory performance to increased depression-like behaviors. The present study scrutinizes the interplay among these variables during the peri-adolescent developmental phase, utilizing Long-Evans rats as the experimental model. Our overarching hypothesis is that rats exposed to either social isolation, a high-fat diet, or both will result in heightened pain sensitivity, diminished cognitive flexibility, and increased neuroinflammatory responses within brain regions implicated in sociability, cognition, memory, and pain processing. Behavioral flexibility will be assessed using a maze-based …

Emotional Content In Working Memory Processes: An Fmri Study., Manal Zafar

Electronic Theses and Dissertations

Working memory (WM) is a dynamic system that processes and manipulates both goal-relevant and goal-irrelevant information, integral to higher-level cognition and executive control (Fujii, 2001; Nyberg & Erikkson, 2016). The processing and manipulation of representations is modulated by the affective nature of the information (Pessoa, 2009) such that negative information can either impair or enhance WM processing. WM impairments are seen commonly across clinical disorders such as depression, anxiety, PTSD and schizophrenia (Levens & Gotlib, 2010; Joorman et a., 2011; Brodziak et al., 2015). Specifically, negative information is known to have differential processing in WM compared to neutral and positive …

The Role Of The Circadian Clock In Disease And Tissue Function, Marvin Wirianto

Dissertations and Theses (Open Access)

The mammalian circadian clock responds to the 24-hour daily cycle and regulates tissue-specific gene expression and downstream physiology. The central pacemaker located in the hypothalamic suprachiasmatic nuclei (SCN) synchronizes the peripheral clocks in different tissues. This dissertation aims to uncover specific circadian regulatory mechanisms in the brain and skeletal muscle.

Alzheimer’s Disease (AD) is the most common type of dementia. It has previously been shown that there is a strong correlation of disease progression with circadian rhythm decline. We showed that circadian modulation by a small molecule Nobiletin (NOB) was able to mitigate AD pathogenesis. Furthermore, NOB significantly alleviated the …

Genomic Data Science Approaches For Understanding Human Diseases, Snehal Shah

All Dissertations

The intricate interplay of genetic predisposition, environmental influences, and lifestyle acts as the multifactorial landscape of diseases. Understanding this complexity presents a significant challenge. Molecular insights into disease mechanisms, particularly the interactions of DNA, RNA, and proteins with environmental and lifestyle factors, have revolutionized disease diagnosis, prognosis, and treatment. High-throughput technologies, such as next-generation sequencing, generate large amounts of molecular data, holding a wealth of knowledge. These datasets unveil the roles of genes and their interactions with various factors through analysis, shedding light on previously unknown molecular mechanisms underlying disease pathogenesis. Furthermore, they facilitate the discovery of biomarkers crucial for …

The Blessed Assembly: Irreplaceable Physical Co-Presence In Worship And Healthy Hybridity Reimagined After The Pandemic In The Digital Age, Yvette, Ying Wai Lau

Doctor of Pastoral Music Projects and Theses

Because of the unprecedented and unexpected force of the pandemic since 2020, most churches around the world have experienced some online worship during the lockdown of their cities or the mandated closure of the church buildings. For many people, online worship seems to be an equivalent, if not better, alternative for gathering together—a physical co-presence in worship—even after the pandemic has ended. As necessary and vital as online worship experiences have been for Christians during the pandemic, the witness of the church from Pentecost throughout Christian history indicates that gathered worship in physical spaces is irreplaceable for faith formation and …

External And Internal Attribution In Human-Agent Interaction: Insights From Neuroscience And Virtual Reality, Nina Lauharatanahirun, Andrea Won, Angel Hsing-Chi Hwang

Human-Machine Communication

Agents are designed in the image of humans, both internally and externally. The internal systems of agents imitate the human brain, both at the levels of hardware (i.e., neuromorphic computing) and software (i.e., neural networks). Furthermore, the external appearance and behaviors of agents are designed by people and based on human data. Sometimes, these humanlike qualities of agents are purposely selected to increase their social influence over human users, and sometimes the human factors that influence perceptions of agents are hidden. Inspired by Blascovich’s “threshold of social influence’, a model designed to explain the effects of different methods of anthropomorphizing …

Embracing The Irreplaceable: The Role Of Neurodiversity In Cultivating Human-Ai Symbiosis In Education, Piper Hutson

International Journal of Emerging and Disruptive Innovation in Education : VISIONARIUM

This study investigates the indispensable role of human skills—such as empathy, ethical judgment, and nuanced understanding—in the development and application of artificial intelligence (AI) within higher education, highlighting the unique contributions of neurodivergent perspectives in creating a symbiotic human-AI relationship. Drawing upon research that evidences the superior performance of diverse teams in creativity and innovation, the paper argues for the integration of neurodiversity into AI development as a means to address the philosophy of 'fearing the Other,' thereby mitigating biases and fostering ethical AI interactions. The technology sector's adoption of Diversity, Equity, and Inclusion (DEI) programs, including biopsychosocial interventions and …