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Articles 91 - 114 of 114

Full-Text Articles in Behavior and Behavior Mechanisms

Specific Relationship Between The Shape Of The Readiness Potential, Subjective Decision Time, And Waiting Time Predicted By An Accumulator Model With Temporally Autocorrelated Input Noise, Aaron Schurger Jan 2018

Specific Relationship Between The Shape Of The Readiness Potential, Subjective Decision Time, And Waiting Time Predicted By An Accumulator Model With Temporally Autocorrelated Input Noise, Aaron Schurger

Psychology Faculty Articles and Research

Self-initiated movements are reliably preceded by a gradual buildup of neuronal activity known as the readiness potential (RP). Recent evidence suggests that the RP may reflect subthreshold stochastic fluctuations in neural activity that can be modeled as a process of accumulation to bound. One element of accumulator models that has been largely overlooked in the literature is the stochastic term, which is traditionally modeled as Gaussian white noise. While there may be practical reasons for this choice, we have long known that noise in neural systems is not white – it is long-term correlated with spectral density of the form …


Volition And Action In The Human Brain: Processes, Pathologies, And Reasons, Itzhak Fried, Patrick Haggard, Biyu J. He, Aaron Schurger Nov 2017

Volition And Action In The Human Brain: Processes, Pathologies, And Reasons, Itzhak Fried, Patrick Haggard, Biyu J. He, Aaron Schurger

Psychology Faculty Articles and Research

Humans seem to decide for themselves what to do, and when to do it. This distinctive capacity may emerge from an ability, shared with other animals, to make decisions for action that are related to future goals, or at least free from the constraints of immediate environmental inputs. Studying such volitional acts proves a major challenge for neuroscience. This review highlights key mechanisms in the generation of voluntary, as opposed to stimulus-driven actions, and highlights three issues. The first part focuses on the apparent spontaneity of voluntary action. The second part focuses on one of the most distinctive, but elusive, …


Precursor Processes Of Human Self-Initiated Action, Nima Khalighinejad, Aaron Schurger, Andrea Desantis, Leor Zmigrod Sep 2017

Precursor Processes Of Human Self-Initiated Action, Nima Khalighinejad, Aaron Schurger, Andrea Desantis, Leor Zmigrod

Psychology Faculty Articles and Research

A gradual buildup of electrical potential over motor areas precedes self-initiated movements. Recently, such “readiness potentials” (RPs) were attributed to stochastic fluctuations in neural activity. We developed a new experimental paradigm that operationalized self-initiated actions as endogenous ‘skip’ responses while waiting for target stimuli in a perceptual decision task. We compared these to a block of trials where participants could not choose when to skip, but were instead instructed to skip. Frequency and timing of motor action were therefore balanced across blocks, so that conditions differed only in how the timing of skip decisions was generated. We reasoned that across-trial …


Chronic Binge Alcohol Administration Dysregulates Hippocampal Genes Involved In Immunity And Neurogenesis In Simian Immunodeficiency Virus-Infected Macaques, John K Maxi, Matt Dean, Jovanny Zabaleta, Krzysztof Reiss, Gregory J. Bagby, Steve Nelson, Peter J. Winsauer, Francesca Peruzzi, Patricia E. Molina Nov 2016

Chronic Binge Alcohol Administration Dysregulates Hippocampal Genes Involved In Immunity And Neurogenesis In Simian Immunodeficiency Virus-Infected Macaques, John K Maxi, Matt Dean, Jovanny Zabaleta, Krzysztof Reiss, Gregory J. Bagby, Steve Nelson, Peter J. Winsauer, Francesca Peruzzi, Patricia E. Molina

School of Graduate Studies Faculty Publications

Alcohol use disorders (AUD) exacerbate neurocognitive dysfunction in Human Immunodeficiency Virus (HIV+) patients. We have shown that chronic binge alcohol (CBA) administration (13-14 g EtOH/kg/wk) prior to and during simian immunodeficiency virus (SIV) infection in rhesus macaques unmasks learning deficits in operant learning and memory tasks. The underlying mechanisms of neurocognitive alterations due to alcohol and SIV are not known. This exploratory study examined the CBA-induced differential expression of hippocampal genes in SIV-infected (CBA/SIV+; = 2) macaques in contrast to those of sucrose administered, SIV-infected (SUC/SIV+; = 2) macaques. Transcriptomes of hippocampal samples dissected from brains obtained at necropsy (16 …


Alzheimer's Biomarkers Are Correlated With Brain Connectivity In Older Adults Differentially During Resting And Task States, Yang Jiang, Haiqing Huang, Erin Abner, Lucas S. Broster, Gregory A. Jicha, Frederick A. Schmitt, Richard Kryscio, Anders H. Andersen, David Powell, Linda J. Van Eldik, Brian T. Gold, Peter T. Nelson, Charles D. Smith, Mingzhou Ding Feb 2016

Alzheimer's Biomarkers Are Correlated With Brain Connectivity In Older Adults Differentially During Resting And Task States, Yang Jiang, Haiqing Huang, Erin Abner, Lucas S. Broster, Gregory A. Jicha, Frederick A. Schmitt, Richard Kryscio, Anders H. Andersen, David Powell, Linda J. Van Eldik, Brian T. Gold, Peter T. Nelson, Charles D. Smith, Mingzhou Ding

Behavioral Science Faculty Publications

β-amyloid (Aβ) plaques and tau-related neurodegeneration are pathologic hallmarks of Alzheimer’s disease (AD). The utility of AD biomarkers, including those measured in cerebrospinal fluid (CSF), in predicting future AD risk and cognitive decline is still being refined. Here, we explored potential relationships between functional connectivity (FC) patterns within the default-mode network (DMN), age, CSF biomarkers (Aβ42 and pTau181), and cognitive status in older adults. Multiple measures of FC were explored, including a novel time series-based measure [total interdependence (TI)]. In our sample of 27 cognitively normal older adults, no significant associations were found between levels of Aβ …


Brain Responses To Biological Motion Predict Treatment Outcome In Young Children With Autism, D. Yang, Kevin Pelphrey, D. Sukholdolsky, M. Crowley, E. Dayan, +6 Additional Authors Jan 2016

Brain Responses To Biological Motion Predict Treatment Outcome In Young Children With Autism, D. Yang, Kevin Pelphrey, D. Sukholdolsky, M. Crowley, E. Dayan, +6 Additional Authors

Pharmacology and Physiology Faculty Publications

Autism spectrum disorders (ASDs) are common yet complex neurodevelopmental disorders, characterized by social, communication and behavioral deficits. Behavioral interventions have shown favorable results—however, the promise of precision medicine in ASD is hampered by a lack of sensitive, objective neurobiological markers (neurobiomarkers) to identify subgroups of young children likely to respond to specific treatments. Such neurobiomarkers are essential because early childhood provides a sensitive window of opportunity for intervention, while unsuccessful intervention is costly to children, families and society. In young children with ASD, we show that functional magnetic resonance imaging-based stratification neurobiomarkers accurately predict responses to an evidence-based behavioral treatment—pivotal …


Chronic Pancreatitis, Pain, And Anxiety In An Alcohol And High Fat Mouse Model, Tiffanie Clinkinbeard Jan 2016

Chronic Pancreatitis, Pain, And Anxiety In An Alcohol And High Fat Mouse Model, Tiffanie Clinkinbeard

Theses and Dissertations--Gerontology

Homeodynamic space (HDS) shrinks as vulnerability increases with aging and repeated damage to the cells. HDS is lost in alcoholic pancreatitis patients due to overconsumption of alcohol, smoking, and high fat diets. Etiologically relevant animal models for study of chronic pancreatitis (CP) are needed. In order to begin filling this gap a central purpose of this dissertation research was to examine relationships between the alcohol and high fat diet (AHF) and pancreatitis with attention to hypersensitivity and anxiety-like behaviors. The AHF diet induced pancreatitis described here etiologically mimics human risk factors of AHF consumption for advancement to alcoholic CP.

In …


Evaluation Of A Diabetes Self-Management Program For Hispanics In Lexington Kentucky: A Pilot Study, Miguel A. Gamboa Oropeza Jan 2016

Evaluation Of A Diabetes Self-Management Program For Hispanics In Lexington Kentucky: A Pilot Study, Miguel A. Gamboa Oropeza

Theses and Dissertations--Nutrition and Food Systems

Hispanics are more affected by diabetes than non-Hispanic whites and they tend to experience more severe complications. Research shows that although self-management is poor among ethnic minorities, it is even more so among Hispanics. The “Taking Ownership of Your Diabetes” (TOYD) program has been shown to be successful in helping individuals manage their diabetes. However, no work has been conducted with Hispanic audiences in Kentucky. TOYD program allows individuals to modify lifestyle risks and solve problems related to diabetes management. The program was translated from English to Spanish. Hispanics males and females between ages 19 to 75 years …


The Effects Of External Focus Of Attention Exercise Rehabilitation On Dual Task Walking In Parkinson's Disease, Eric N. Beck Jan 2016

The Effects Of External Focus Of Attention Exercise Rehabilitation On Dual Task Walking In Parkinson's Disease, Eric N. Beck

Theses and Dissertations (Comprehensive)

Parkinson’s disease impairs control of well-learned movements, and therefore, individuals with Parkinson’s disease are forced to walk with greater conscious control. This causes difficulties while walking and completing a secondary task simultaneously (dual tasking), in that distractions from conscious control of walking increase the risk of falls and injury. Although, attention-based exercise may be a potential avenue to decrease the demands associated with walking in Parkinson’s disease. For example, an external focus of attention (on manipulated objects) has been found to recruit the networks that are important for walking with little conscious control (automatic control networks). In contrast, an internal …


Visual Feedback Dominates The Sense Of Agency For Brain-Machine Actions, Nathan Evans, Steven Gale, Aaron Schurger, Olaf Blanke Jun 2015

Visual Feedback Dominates The Sense Of Agency For Brain-Machine Actions, Nathan Evans, Steven Gale, Aaron Schurger, Olaf Blanke

Psychology Faculty Articles and Research

Recent advances in neuroscience and engineering have led to the development of technologies that permit the control of external devices through real-time decoding of brain activity (brain-machine interfaces; BMI). Though the feeling of controlling bodily movements (sense of agency; SOA) has been well studied and a number of well-defined sensorimotor and cognitive mechanisms have been put forth, very little is known about the SOA for BMI-actions. Using an on-line BMI, and verifying that our subjects achieved a reasonable level of control, we sought to describe the SOA for BMI-mediated actions. Our results demonstrate that discrepancies between decoded neural activity and …


Exposure To Kynurenic Acid During Adolescence Increases Sign-Tracking And Impairs Long-Term Potentiation In Adulthood, Nicole E. Deangeli, Travis P. Todd, Stephen E. Chang, Hermes H. Yeh, Pamela W. Yeh, David J. Bucci Jan 2015

Exposure To Kynurenic Acid During Adolescence Increases Sign-Tracking And Impairs Long-Term Potentiation In Adulthood, Nicole E. Deangeli, Travis P. Todd, Stephen E. Chang, Hermes H. Yeh, Pamela W. Yeh, David J. Bucci

Dartmouth Scholarship

Changes in brain reward systems are thought to contribute significantly to the cognitive and behavioral impairments of schizophrenia, as well as the propensity to develop co-occurring substance abuse disorders. Presently, there are few treatments for persons with a dual diagnosis and little is known about the neural substrates that underlie co-occurring schizophrenia and substance abuse. One goal of the present study was to determine if a change in the concentration of kynurenic acid (KYNA), a tryptophan metabolite that is increased in the brains of people with schizophrenia, affects reward-related behavior. KYNA is an endogenous antagonist of NMDA glutamate receptors and …


Using The Symmetry Of False Matches To Solve The Correspondence Problem, Cherlyn J. Ng, Bart Farell Jan 2015

Using The Symmetry Of False Matches To Solve The Correspondence Problem, Cherlyn J. Ng, Bart Farell

Biomedical and Chemical Engineering - All Scholarship

Veridical stereoscopic depth depends on matching corresponding image points. This requires solving the stereo correspondence problem: how are true matches distinguished from false ones? Conventional algorithms select true matches on the basis of feature detection [what do you mean by ‘feature detection’ here? Is there some more specific term?] and adherence to natural statistics. They reject false matches as noise. We propose here an alternative that uses the signals present in false matches to delineate the true solution. When visualized in a Keplerian array, binocular matches are symmetrically reflected about an axis that is a potential solution. Properties such as …


Development Of An Avian Model For Identifying Individual Differences In Drug Vulnerability, Beth A. Rice Jan 2015

Development Of An Avian Model For Identifying Individual Differences In Drug Vulnerability, Beth A. Rice

Theses and Dissertations--Psychology

The attribution of incentive salience to cues that become associated with drugs of abuse is a critical characteristic of individuals who may be vulnerable to drug addiction. Rodents with the propensity to sign track are thought to be vulnerable to drug abuse. The goal of the current work was to investigate whether sign trackers (STs) would acquire cocaine conditioned place preference (CPP) to a discrete cue using an avian species. In Experiment 1, sign and goal trackers (GTs) were first identified using a one third rank order split. Following identification, cocaine-CPP was conducted with a discrete cue in each end …


Accommodating Hyperaroused Information Processing In Persons At Risk For Alcoholism, Kellianne Clark, Jaclyn Cutler Dec 2014

Accommodating Hyperaroused Information Processing In Persons At Risk For Alcoholism, Kellianne Clark, Jaclyn Cutler

Student Scholar Symposium Abstracts and Posters

In the search for the factors related to the heightened alcoholism risk in adult children of alcoholics (ACOA), it has been reported that these persons possess a high incidence of attention deficit disorders (ADD) as determined by clinical assessment instruments. However, investigations of alcoholism risk and ADD indicate that, in contrast to the hypoarousal model of ADD, the ACOA’s attention problems represent hyperarousal of attention mechanisms resulting in reduced ability to select and encode relevant information. If true, then unlike persons with ADD, clinical and cognitive assessments of ACOAs would benefit if the ACOA was provided with more time to …


On Reporting The Onset Of The Intention To Move, Uri Maoz, Liad Mudrik, Ram Rivlin, Ian Ross, Adam Mamelak, Gideon Yaffe Nov 2014

On Reporting The Onset Of The Intention To Move, Uri Maoz, Liad Mudrik, Ram Rivlin, Ian Ross, Adam Mamelak, Gideon Yaffe

Psychology Faculty Books and Book Chapters

"In 1965, Hans Kornhuber and Luder Deecke made a discovery that greatly influenced the study of voluntary action. Using electroencephalography (EEG), they showed that when aligning some tens of trials to movement onset and averaging, a slowly decreasing electrical potential emerges over central regions of the brain. It starts 1 second ( s) or so before the onset of the voluntary action1 and continues until shortly after the action begins. They termed this the Bereitschaftspotential, or readiness potential (RP; Kornhuber & Deecke, 1965).2 This became the first well-established neural marker of voluntary action. In that, the RP allowed for more …


The Reversal Effects Of Curcumin, An Herbal Remedy, On The Impairments Induced By Vmat-2 Inhibitor Tetrabenazine, Emily Qian, Samantha E. Yohn May 2014

The Reversal Effects Of Curcumin, An Herbal Remedy, On The Impairments Induced By Vmat-2 Inhibitor Tetrabenazine, Emily Qian, Samantha E. Yohn

Honors Scholar Theses

Substantial evidence has shown that dopamine (DA), particularly in the nucleus accumbens (NAc), is involved in behavioral activation and effort-related processes, such as overcoming work related response costs. Interference with accumbens DA transmission through administration of the vesicular monoamine transportor-2 (VMAT-2) inhibitor tetrabenazine (TBZ) produces an alteration of response allocation in the concurrent FR5/chow choice procedure, biasing animals toward the lower effort alternative. It has been suggested that these drug-induced shifts in effort-related choice behavior seen in rodents are analogous to symptoms such as psychomotor retardation, anergia, and fatigue, which can be observed in people with depression and other related …


Eye-Tracking Measures Of Attentional Bias In Cocaine Dependent Subjects, Nadeeka Dias May 2014

Eye-Tracking Measures Of Attentional Bias In Cocaine Dependent Subjects, Nadeeka Dias

Dissertations and Theses (Open Access)

Cocaine-dependent (CD) subjects show evidence of attentional bias toward cocaine-related cues, and this measure of cue-reactivity is predictive of craving and relapse. In previous work, cue-reactivity and attentional bias have been assessed by models that present drug-relevant stimuli (e.g., cocaine-specific Stroop task) and measure physiological and behavioral reactivity (e.g., heart rate, reaction times). Studies have indicated competition between the higher-order cortical processes (frontal eye-fields, DLPFC) in voluntary eye control (i.e., anti-saccades) and more reflexive saccades driven by involuntary midbrain (superior colliculus) perceptual input (i.e., pro-saccades). In addition, neuroimaging studies in patients with cocaine dependence have shown activation in frontal regions …


Network Dynamics Of Visual Naming, Christopher R. Conner Aug 2013

Network Dynamics Of Visual Naming, Christopher R. Conner

Dissertations and Theses (Open Access)

Recognition and naming of objects and actions are fundamental components of language. They involve several different systems working in coordination to accomplish a complex behavior. During visual naming, sensory and semantic processing are carried out by dedicated cortical substrates in the temporal and occipital lobes, while response selection and articulatory planning are handled by prefrontal cortex. Despite decades of research using lesion analysis, functional MRI and electro-encephalography, the precise dynamics involved remain unknown due to the inadequate spatio-temporal resolution of these methodologies. Of particular interest is the organization of semantic knowledge and the degree of serial and parallel organization of …


Does N-Acetylcysteine Supplementation Alleviate Compulsive Behavior In Adults With Impulse Control Disorders?, Tova Diamond Jan 2013

Does N-Acetylcysteine Supplementation Alleviate Compulsive Behavior In Adults With Impulse Control Disorders?, Tova Diamond

PCOM Physician Assistant Studies Student Scholarship

OBJECTIVE: The objective of this systematic review is to determine whether or not “Does N-acetylcysteine supplementation alleviate compulsive behavior in adults with impulse control disorders?”

STUDY DESIGN: Review of three English primary studies published between 2007 and 2009.

DATA SOURCES: One double-blind RCT, one open label trial followed by double-blind RCT, one case study. Studies were found using PubMed, Cochrane Systematic Reviews, OVID and Ebsco databases.

OUTCOMES MEASURED: Primary outcomes measured include severity of trichotillomania symptoms measured by MGHHPS, reduction of pathological gambling symptoms measured by YBOCS-PG, and reduction of compulsive grooming urges measured by patient reports.

RESULTS: In …


Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung Dec 2012

Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung

Physiology and Pharmacology Publications

We hypothesize that selective lesion of the septohippocampal GABAergic neurons suppresses the altered behaviors induced by an N-methyl-D-aspartate (NMDA) receptor antagonist, ketamine or MK-801. In addition, we hypothesize that septohippocampal GABAergic neurons generate an atropine-resistant theta rhythm that coexists with an atropine-sensitive theta rhythm in the hippocampus. Infusion of orexin-saporin (ore-SAP) into the medial septal area decreased parvalbumin-immunoreactive (GABAergic) neurons by ~80%, without significantly affecting choline-acetyltransferase-immunoreactive (cholinergic) neurons. The theta rhythm during walking, or the immobility-associated theta induced by pilocarpine, was not different between ore-SAP and sham-lesion rats. Walking theta was, however, more disrupted by atropine sulfate in ore-SAP than …


Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner Jan 2011

Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner

Department of Political Science: Faculty Publications

Prior research has shown that the orbitofrontal cortex (OFC) plays an important role in the representation of the evaluation of stimuli, regardless of stimulus modality. Based on these findings, researchers have proposed that the OFC serves a common currency function, allowing for the direct comparison of different types of perceptual stimuli (e.g. food, drink, money). The present study was designed to extend this research and investigate whether these same regions of OFC that have been identified in previous research are involved in evaluating imagined stimuli. Specifically, we asked participants to draw on prior attitudinal knowledge to generate internal representations of …


Eye Movement, Rem Sleep And Adhd: An Examination Of Eye Movement Patterns During Rem Sleep In Adhd Populations, Elin Marie Grissom Dec 2008

Eye Movement, Rem Sleep And Adhd: An Examination Of Eye Movement Patterns During Rem Sleep In Adhd Populations, Elin Marie Grissom

All-Inclusive List of Electronic Theses and Dissertations

The current study investigates differences in patterns of eye movement and sleep architecture during REM stage sleep in children with a diagnosis of ADHD, compared to those without the diagnosis. Existing studies have found differences in eye movement patterns during waking hours in these two groups (Munoz, Armstrong, Hampton, & Moore, 2003; O'Laughlin, Brubaker, Gay, Deans, & Aaron, 2006) as well as differences in patterns of REM sleep. The current study will focus on the fine structure of eye movement in REM in children with and without ADHD. Using pediatric polysomnographic recordings, the frequency, density, strength, and inferred direction of …


Economic Efficiency And Consumer Choice Theory In Nutritional Labeling, Michael Mccann Jan 2004

Economic Efficiency And Consumer Choice Theory In Nutritional Labeling, Michael Mccann

Law Faculty Scholarship

As more Americans consume fast food each year, more Americans are contracting serious diseases related to obesity. Considering that obesity ranks second behind tobacco use as the largest contributor to mortality rates in the United States, and also that it gives rise to greater publicly funded health care expenses than does tobacco, this phenomenon begs the obvious question: To what extent does the growing consumption of fast food contribute to the obesity epidemic and the incidence of disease? If the answer indicates a meaningful contribution, a natural follow-up question then emerges: In a sensible legal system, what instruments would best …


The Efficacy Of Biofeedback In The Treatment Of Tension Headaches, Micahel Earl Waters Aug 1987

The Efficacy Of Biofeedback In The Treatment Of Tension Headaches, Micahel Earl Waters

Graduate Theses

Fifteen adults from the general population with chronic tension headaches were divided into four groups. Four were assigned to relaxation instructions, biofeedback (EMG and temperature), and home relaxation practice; four were assigned to relaxation instructions and biofeedback; four were assigned to biofeedback alone; and three were assigned to a no-treatment group. Subjects completed a ten-day baseline period followed by a three-week treatment period. Measures were taken of headache frequency, duration, intensity, frontalis EMG, and temperature recordings. Comparisons of pre- and post-treatment data indicated that not one treatment group was significantly different from any other treatment group, including the no-treatment group, …