A Principle Of Economy Predicts The Functional Architecture Of Grid Cells, Xue-Xin Wei, Jason Prentice, Vijay Balasubramanian

Publications and Research

Grid cells in the brain respond when an animal occupies a periodic lattice of ‘grid fields’ during navigation. Grids are organized in modules with different periodicity. We propose that the grid system implements a hierarchical code for space that economizes the number of neurons required to encode location with a given resolution across a range equal to the largest period. This theory predicts that (i) grid fields should lie on a triangular lattice, (ii) grid scales should follow a geometric progression, (iii) the ratio between adjacent grid scales should be √e for idealized neurons, and lie between 1.4 and 1.7 …

Reducing Subjectivity: Meditation And Implicit Bias, Diana M. Ciuca

CMC Senior Theses

Implicit association of racial stereotypes is brought about by social conditioning (Greenwald & Krieger, 2006). This conditioning can be explained by attractor networks (Sharp, 2011). Reducing implicit bias through meditation can show the effectiveness of reducing the rigidity of attractor networks, thereby reducing subjectivity. Mindfulness meditation has shown to reduce bias from the use of one single guided session conducted before performing an Implicit Association Test (Lueke & Gibson, 2015). Attachment to socially conditioned racial bias should become less prevalent through practicing meditation over time. An experimental model is proposed to test this claim along with a reconceptualization of consciousness …

Influence Of Planning Resources On Gait Control In Parkinson’S Disease, Frederico P. Faria

Theses and Dissertations (Comprehensive)

Movement disturbances in individuals with Parkinson’s disease (PD) have been associated with difficulties to plan complex actions. Performance of simple and complex actions overloads resources for individuals with Parkinson’s disease (PD). However, it is unclear if central resources required to plan gait adjustments while walking exacerbate gait disturbances of patients with PD. More specifically, it is unclear how gait impairments, sensory processing, and the dopaminergic system influence the load on processing resources (e.g. cognitive load) during the planning of step modifications. In order to investigate the relative influence of these factors on cognitive load and its impact on gait control, …

Attentional Blink: An Antecedent To Binge Eating Behavior, Gregory Denke

LSU New Orleans Theses and Dissertations

This study examined how attentional sub-processes contribute to binge-eating. Dense-array EEG and a version of the canonical attentional blink task were used to ascertain the neural correlates underlying the attentional sub-processes that comprise the Posner model of attention (alerting, orienting, and executive control) and how attentional activation differs for binge-eaters vs. non-binge eaters. Furthermore, we examined a number of the event-related potentials (ERP), including P2 activation, which has been linked with orientating of attention, and N2 activation which has been linked with attentional conflict. We found decreased P2 activation for binge-eaters, in the negative condition, for incorrect target 2 (T2) …

Cognitive Neurosciene And Its Applications To Contemporary Acting Theory, Ryan Stiffelman

Student Scholar Symposium Abstracts and Posters

I personally believe that anyone can be a performer so long as they have the determination, dedication, and refuse to take no for an answer. There are all kinds of training out there designed to help turn hopeful wannabes into the “stars” that we know them as, however, not every “star” we see has had this kind of training. We often hear of young actors like Jennifer Lawrence hailed for their “natural talent”. Does this mean there’s some kind of birth-right, a specific natural inclination or ability that makes someone a potentially great actor from the start? I will refer …

A Movement Tool Kit For The Divergent And Convergent Cps Guidelines: Instruction Cards And Activity Floor Mats, Adela Vangelisti

Creativity and Change Leadership Graduate Student Master's Projects

A Movement Tool Kit for the Divergent and Convergent CPS Guidelines:

Instruction Cards and Activity Floor Mats

Movement is as natural to humans as breathing is, and, yet, passivity starts early in schools. We are taught to sit still and in silence for long periods of time. By the time we reach adulthood and enter the workforce, we have almost forgotten our sense of embodiment. This lack of movement is counter-productive, not only to learning but to the development of creativity as well. For this project, I designed a tool to recapture the joy and playfulness of movement. Furthermore, the …

The Phenomenon Of Abstract Cognition Among Scholastic Chess Participants: A Case Study, Brent C. Laws

Electronic Theses and Dissertations

A qualitative investigation was conducted to explore the phenomenon of abstract cognition among a purposive sample of 5 secondary scholastic chess club participants. The case study enabled the researcher to explore the faculties of abstract cognition among students of contrasting skills and abilities in playing chess. The study also allowed for the consideration of potential visual-spatial, logical, academic, social competency and life benefits of chess play. Through analysis of interviews, chess simulations, blindfold chess play, and narration of chess lines and sequences, the investigator was able to extract meaning and code schemata into a holistic understanding of the phenomenon of …

Effects Of Oxytocin On Human Aggression, Joseph L. Alcorn Iii

Dissertations and Theses (Open Access)

EFFECTS OF OXYTOCIN ON HUMAN AGGRESSION

Joseph Louis Alcorn III, B.S.

Advisory Professor: Scott D. Lane, Ph.D.

Human interaction is comprised of common, yet complex, behaviors and the outcomes of these social behaviors can beneficially or detrimentally impact individual and public health. One social behavior that can have profound detrimental outcomes is aggression. Aggression is a class of social behavior that is particularly prevalent in individuals with antisocial personality disorder (ASPD) and comorbid substance use disorder (SUD). Aggression in these individuals can manifest at maladaptive levels that place considerable burdens on public health and communities. Therefore, understanding the neurobehavioral underpinnings …

Change Detection In Rhesus Monkeys And Humans, Deepna T. Devkar, Deepna T. Devkar

Dissertations and Theses (Open Access)

Visual working memory (VWM) is the temporary retention of visual information and a key component of cognitive processing. The classical paradigm for studying VWM and its encoding limitations has been change detection. Early work focused on how many items could be stored in VWM, leading to the popular theory that humans could remember no more than 4±1 items. More recently, proposals have suggested that VWM is a noisy, continuous resource distributed across virtually all items in the visual field, resulting in diminished memory quality rather than limited quantity. This debate about the nature of VWM has predominantly been studied with …

Discovery Of Thienoquinolone Derivatives As Selective And Atp Non-Competitive Cdk5/P25 Inhibitors By Structure-Based Virtual Screening, Arindam Chatterjee, Stephen J. Cutler, Robert J. Doerksen, Ikhlas A. Khan, John S. Williamson

Office for Research Publications and Presentations

Calpain mediated cleavage of CDK5 natural precursor p35 causes a stable complex formation of CDK5/p25, which leads to hyperphosphorylation of tau. Thus inhibition of this complex is a viable target for numerous acute and chronic neurodegenerative diseases involving tau protein, including Alzheimer’s disease. Since CDK5 has the highest sequence homology with its mitotic counterpart CDK2, our primary goal was to design selective CDK5/p25 inhibitors targeting neurodegeneration. A novel structure-based virtual screening protocol comprised of e-pharmacophore models and virtual screening workflow was used to identify nine compounds from a commercial database containing 2.84 million compounds. An ATP non-competitive and selective thieno[3,2- …

Focal Cortical Thickness Correlates Of Exceptional Memory Training In Vedic Priests, Giridhar P. Kalamangalam, Timothy M. Ellmore

Publications and Research

The capacity for semantic memory—the ability to acquire and store knowledge of the world—is highly developed in the human brain. In particular, semantic memory assimilated through an auditory route may be a uniquely human capacity. One method of obtaining neurobiological insight into memory mechanisms is through the study of experts. In this work, we study a group of Hindu Vedic priests, whose religious training requires the memorization of vast tracts of scriptural texts through an oral tradition, recalled spontaneously during a lifetime of subsequent spiritual practice. We demonstrate focal increases of cortical thickness in regions of the left prefrontal lobe …

Dynamics Of Alpha Control: Preparatory Suppression Of Posterior Alpha Oscillations By Frontal Modulators Revealed With Combined Eeg And Event-Related Optical Signal, Kyle E. Mathewson, Diane M. Beck, Tony Ro, Edward L. Maclin, Kathy A. Low, Monica Fabiani, Gabriele Gratton

Publications and Research

We investigated the dynamics of brain processes facilitating conscious experience of external stimuli. Previously, we proposed that alpha (8–12 Hz) oscillations, which fluctuate with both sustained and directed attention, represent a pulsed inhibition of ongoing sensory brain activity. Here we tested the prediction that inhibitory alpha oscillations in visual cortex are modulated by top–down signals from frontoparietal attention networks. We measured modulations in phase-coherent alpha oscillations from superficial frontal, parietal, and occipital cortices using the event-related optical signal (EROS), a measure of neuronal activity affording high spatiotemporal resolution, along with concurrently recorded EEG, while participants performed a visual target detection …

Dissociation Between Face Perception And Face Memory In Adults, But Not Children, With Developmental Prosopagnosia, Kirsten A. Dalrymple, Lúcia Garrido, Brad Duchaine

Dartmouth Scholarship

Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP). To address this issue, we tested the face perception and face memory of children and adults with DP. By …

Sticking Your Neck Out And Burying The Hatchet: What Idioms Reveal About Embodied Simulation, Natalie A. Kacinik

Publications and Research

Idioms are used in conventional language twice as frequently as metaphors, but most research, particularly recent work on embodiment has focused on the latter. However, idioms have the potential to significantly deepen our understanding of embodiment because their meanings cannot be derived from their component words. To determine whether sensorimotor states could activate idiomatic meaning, participants were instructed to engage in postures/actions reflecting various idioms (e.g.,sticking your neck out) relative to non-idiomatic control postures/actions while reading and responding to statements designed to assess idiomatic meaning. The results showed that statements were generally more strongly endorsed after idiom embodiment than control …

Hemispheric Asymmetry In New Neurons In Adulthood Is Associated With Vocal Learning And Auditory Memory, Shuk C. Tsoi, Utsav V. Aiya, Kobi D. Wasner, Mimi L. Phan, Carolyn L. Pytte, David S. Vicario

Publications and Research

Many brain regions exhibit lateral differences in structure and function, and also incorporate new neurons in adulthood, thought to function in learning and in the formation of new memories. However, the contribution of new neurons to hemispheric differences in processing is unknown. The present study combines cellular, behavioral, and physiological methods to address whether 1) new neuron incorporation differs between the brain hemispheres, and 2) the degree to which hemispheric lateralization of new neurons correlates with behavioral and physiological measures of learning and memory. The songbird provides a model system for assessing the contribution of new neurons to hemispheric specialization …

Integrating Cognitive Science With Innovative Teaching In Stem Disciplines, Mark A. Mcdaniel, Regina F. Frey, Susan M. Fitzpatrick, Henry L. Roediger Iii

Books and Monographs

This volume collects the ideas and insights discussed at a novel conference, the Integrating Cognitive Science with Innovative Teaching in STEM Disciplines Conference, which was held September 27-28, 2012 at Washington University in St. Louis. With funding from the James S. McDonnell Foundation, the conference was hosted by Washington University’s Center for Integrative Research on Cognition, Learning, and Education (CIRCLE), a center established in 2011. Available for download as a PDF. Titles of individual chapters can be found at http://openscholarship.wustl.edu/circle_book/.

Online Tracking Of The Contents Of Conscious Perception Using Real-Time Fmri, Christoph Reichert, Robert Fendrich, Johannes Bernarding, Claus Tempelmann, Hermann Hinrichs, Jochem W. Rieger

Dartmouth Scholarship

Perception is an active process that interprets and structures the stimulus input based on assumptions about its possible causes. We use real-time functional magnetic resonance imaging (rtfMRI) to investigate a particularly powerful demonstration of dynamic object integration in which the same physical stimulus intermittently elicits categorically different conscious object percepts. In this study, we simulated an outline object that is moving behind a narrow slit. With such displays, the physically identical stimulus can elicit categorically different percepts that either correspond closely to the physical stimulus (vertically moving line segments) or represent a hypothesis about the underlying cause of the physical …

The New Normal: Goodness Judgments Of Non-Invariant Speech, Julia R. Drouin

Honors Scholar Theses

Previous research has found that perceptual learning, or normalizing the idiosyncratic phonemes of speech, causes a shift in speech sound category boundaries. The present study examined if perceptual learning was limited to the boundary or if also caused a shift in internal category structure. Seventeen individuals participated in three behavioral tasks to explicate this question. In the Lexical Decision task, participants were trained in either /s/-biasing or /ʃ/- biasing context. In the Goodness Judgment task, participants rated a continuum of sounds on perceived /s/ goodness using a designated scale. Finally, in the Phoneme Identification task, participants listened to the same …

Effects Of Resting State On Perceptual Learning, Sarah Eagleman Ph.D.

Dissertations and Theses (Open Access)

Psychophysical experiments in humans have demonstrated that improvements in perceptual learning tasks occur following daytime rests. The neural correlates of how rest influences subsequent sensory processing during these tasks remain unclear. One possible neural mechanism that may underlie this behavioral improvement is reactivation. Previously evoked network activity reoccurs – reactivates - in the absence of further stimulation. Reactivation was initially discovered in the hippocampus but has now been found in several brain areas including cortex. This phenomenon has been implicated as a general mechanism by which neural networks learn and store sensory information. However, whether reactivation occurs in areas relevant …

Movement-Based Embodied Contemplative Practices: Definitions And Paradigms, Laura Schmalzl, Mardi A. Crane-Godreau, Peter Payne

Dartmouth Scholarship

Over the past decades, cognitive neuroscience has witnessed a shift from predominantly disembodied and computational views of the mind, to more embodied and situated views of the mind. These postulate that mental functions cannot be fully understood without reference to the physical body and the environment in which they are experienced. Within the field of contemplative science, the directing of attention to bodily sensations has so far mainly been studied in the context of seated meditation and mindfulness practices. However, the cultivation of interoceptive, proprioceptive and kinesthetic awareness is also said to lie at the core of many movement-based contemplative …

Normal Acquisition Of Expertise With Greebles In Two Cases Of Acquired Prosopagnosia, Constantin Rezlescu, Jason J. S. Barton, David Pitcher, Bradley Duchaine

Dartmouth Scholarship

Face recognition is generally thought to rely on different neurocognitive mechanisms than most types of objects, but the specificity of these mechanisms is debated. One account suggests the mechanisms are specific to upright faces, whereas the expertise view proposes the mechanisms operate on objects of high within-class similarity with which an observer has become proficient at rapid individuation. Much of the evidence cited in support of the expertise view comes from laboratory-based training experiments involving computer-generated objects called greebles that are designed to place face-like demands on recognition mechanisms. A fundamental prediction of the expertise hypothesis is that recognition deficits …

The Developmental Trajectory Of Contour Integration In Autism Spectrum Disorders, Ted S. Altschuler

Dissertations, Theses, and Capstone Projects

Sensory input is inherently ambiguous and complex, so perception is believed to be achieved by combining incoming sensory information with prior knowledge. One model envisions the grouping of sensory features (the local dimensions of stimuli) to be the outcome of a predictive process relying on prior experience (the global dimension of stimuli) to disambiguate possible configurations those elements could take. Contour integration, the linking of aligned but separate visual elements, is one example of perceptual grouping. Kanizsa-type illusory contour (IC) stimuli have been widely used to explore contour integration processing. Consisting of two conditions which differ only in the alignment …

Direct Control Of Visual Perception With Phase-Specific Modulation Of Posterior Parietal Cortex, Andrew Jaegle, Tony Ro

Publications and Research

We examined the causal relationship between the phase of alpha oscillations (9–12 Hz) and conscious visual perception using rhythmic TMS (rTMS) while simultaneously recording EEG activity. rTMS of posterior parietal cortex at an alpha frequency (10 Hz), but not occipital or sham rTMS, both entrained the phase of subsequent alpha oscillatory activity and produced a phase-dependent change on subsequent visual perception, with lower discrimination accuracy for targets presented at one phase of the alpha oscillatory waveform than for targets presented at the opposite phase. By extrinsically manipulating the phase of alpha before stimulus presentation, we provide direct evidence that the …

Short-Term Activity-Dependent Changes In Schaffer Collateral Axon Function, Benjamin Michael Owen

Theses, Dissertations and Capstones

Schaffer collaterals are the unmyelinated axons of pyramidal neurons in the CA3 area of the hippocampus, a brain structure essential for memory formation. Schaffer collateral axons conduct electrical signals in the form of action potentials from CA3 pyramidal cells to synaptic terminals in area CA1. The fidelity with which these axons conduct action potentials determines the nature of the information which can be transmitted between areas CA3 and CA1. Conduction fidelity may be affected by both normal and abnormal patterns of firing, fluctuations in ion concentration, and some drugs and toxins. In this dissertation, I examined the function of Schaffer …

Perceived Depth In Non-Transitive Stereo Displays, Bart Farell, Cherlyn J. Ng

Biomedical and Chemical Engineering - All Scholarship

The separation between the eyes shapes the distribution of binocular disparities and gives a special role to horizontal disparities. However, for one-dimensional stimuli, disparity direction, like motion direction, is linked to stimulus orientation. This makes the perceived depth of one-dimensional stimuli orientation dependent and generally non-veridical. It also allows perceived depth to violate transitivity. Three stimuli, A, B, and C, can be arranged such that A > B (stimulus A is seen as farther than stimulus B when they are presented together) and B > C, yet A 6 C. This study examines how the visual system handles the depth of A, …

The Neural Substrates Of Natural Reading: A Comparison Of Normal And Nonword Text Using Eyetracking And Fmri, W. Choi, Rutvik Desai, J. M. Henderson

Faculty Publications

Most previous studies investigating the neural correlates of reading have presented text using serial visual presentation (SVP), which may not fully reflect the underlying processes of natural reading. In the present study, eye movements and BOLD data were collected while subjects either read normal paragraphs naturally or moved their eyes through “paragraphs” of pseudo-text (pronounceable pseudowords or consonant letter strings) in two pseudo-reading conditions. Eye movement data established that subjects were reading and scanning the stimuli normally. A conjunction fMRI analysis across natural- and pseudo-reading showed that a common eye-movement network including frontal eye fields (FEF), supplementary eye fields (SEF), …

Examining The Intersection Of The Cognitive Advantages And Disadvantages Of The Bilingual Brain, Irina Rabkina

Scripps Senior Theses

Two conflicting findings characterize cognitive processing accompanying bilingualism. The “bilingual advantage” refers to improved cognitive performance for bilingual compared to monolingual participants. Most bilingual advantages fall under the umbrella of cognitive control mechanisms, most frequently demonstrated using the Stroop task and the Simon task (e.g., Bialystok, 2008; Coderre, Van Heuven, & Conklin, 2013). The “bilingual disadvantage,” on the other hand, refers to bilinguals’ diminished performance on tasks that require word retrieval or switching between languages. This study examined the intersection of the bilingual advantage and the bilingual disadvantage to investigate whether they stem from a single cognitive control process. The …

Variance Predicts Salience In Central Sensory Processing, Ann M. Hermundstad, John J. Briguglio, Mary M. Conte, Jonathan D. Victor, Vijay Balasubramanian, Gašper Tkačik

Publications and Research

Information processing in the sensory periphery is shaped by natural stimulus statistics. In the periphery, a transmission bottleneck constrains performance; thus efficient coding implies that natural signal components with a predictably wider range should be compressed. In a different regime—when sampling limitations constrain performance—efficient coding implies that more resources should be allocated to informative features that are more variable. We propose that this regime is relevant for sensory cortex when it extracts complex features from limited numbers of sensory samples. To test this prediction, we use central visual processing as a model: we show that visual sensitivity for local multi-point …

The Effects Of Anxiety On Sensory Gating, Jonathon Meier

Honors Projects

Sensory gating is a proposed important physiological process of inhibiting neuronal responses of repetitious stimuli in the central nervous system to allocate more cognitive resources to additional salient information. Sensory gating is currently being studied to better understand psychiatric illnesses, especially those characterized by emotional changes and the inability to concentrate such as schizophrenia, ADHD, anxiety disorder, and Parkinson’s. Anxiety is a strong feeling of nervousness that occurs in all individuals at varying degrees and is associated with detrimental health effects as well as hindering concentration. Numerous brain regions are associated with anxiety levels such as the anterior limbic system, …

Time, Perspectives, Verbs, And Imagining Events, Jeffrey P. Hong

Theses and Dissertations (Comprehensive)

During the processing of verbs, readers form internal representations of the events described by those verbs. Two key elements in the construction of event representations are temporal information, given by the verbs that describe the represented events, and the visual perspective from which the events are represented. The current study is composed of two experiments aimed at examining the roles these two factors play in event representation. Specifically, the study aimed to determine how temporal information and visual perspective are represented during event imagination.

Experiment 1 investigated the role of temporal information associated with verbs, given by grammatical aspect (GA) …