Life Sciences Commons^™

Reaching For The Light: The Prioritization Of Conspicuous Visual Stimuli For Reflexive Target-Directed Reaching, Daniel K. Wood

Electronic Thesis and Dissertation Repository

The degree to which something stands out against the background of its environment communicates important information. The phenomenon of camouflage is a testament of the degree to which visual salience and probability of survival tend to overlap. Salient stimuli often elicit fast, reflexive movements in order to catch prey or avoid a predator. The overarching goal of the work presented in this thesis is to investigate how the physical salience of visual stimuli influence the programming and execution of reaching movements. I approached this question by recording kinematics and muscle responses during reaching movements. Broadly, this thesis investigates the effect …

Contribution Of Trpm2 To Memory Loss In An Alzheimer's Mouse Model, Megan M. Chen

Electronic Thesis and Dissertation Repository

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by the progressive deterioration of memory and other intellectual abilities. Accumulation of amyloid-β (Aβ) peptide, the major contributor to the senile plaques central to AD, is thought to mediate neurotoxicity by inducing oxidative stress and calcium dysregulation. Transient Receptor Potential Melastatin type 2 (TRPM2) is a calcium permeable, non-selective cation channel activated under oxidative stress and ultimately induces cell death. The APPSWE/PSEN1ΔE9 double transgenic mouse model carries the human APPswe (Swedish mutations K594N/M595L) and PS1 mutations with a deletion in exon 9 (PS1-dE9), and is one of the most commonly used AD …

Spatial Warping By Oriented Line Detectors Can Counteract Neural Delays, Don A. Vaughn, David M. Eagleman

Faculty Publications

The slow speed of neural transmission necessitates that cortical visual information from dynamic scenes will lag reality. The "perceiving the present" (PTP) hypothesis suggests that the visual system can mitigate the effect of such delays by spatially warping scenes to look as they will in ~100 ms from now (Changizi, 2001). We here show that the Hering illusion, in which straight lines appear bowed, can be induced by a background of optic flow, consistent with the PTP hypothesis. However, importantly, the bowing direction is the same whether the flow is inward or outward. This suggests that if the warping is …

Is Pressure Stressful? The Impact Of Pressure On The Stress Response And Category Learning, Shannon L. Mccoy, Steven B. Hutchinson, Lauren Hawthorne, Brandon J. Cosley, Shawn W. Ell

Psychology Faculty Scholarship

We examine the basic question of whether pressure is stressful. We propose that when examining the role of stress or pressure in cognitive performance it is important to consider the type of pressure, the stress response, and the aspect of cognition assessed. In Experiment 1, outcome pressure was not experienced as stressful but did lead to impaired performance on a rule-based (RB) category learning task and not a more procedural information-integration (II) task. In Experiment 2, the addition of monitoring pressure resulted in a modest stress response to combined pressure and impairment on both tasks. Across experiments, higher stress appraisals …

Taking Tone Into Account: Cognitive Neuroscientific Investigations Of Mandarin Chinese Spoken Word Processing, Jeffrey G. Malins

Electronic Thesis and Dissertation Repository

To date, theories of how humans recognize spoken words have yet to account for tonal languages such as Mandarin Chinese. One reason for this is that we know relatively little about how native speakers of tonal languages process spoken words in the brain. This dissertation addresses this problem by examining Mandarin spoken word processing in both adult native speakers and typically developing children. In adults, functional magnetic resonance imaging (fMRI) was used to assess the extent to which the brain regions involved in processing tonal information are distinct from those involved in vowel processing (Chapter 2), while event related potentials …

Network Structure And Dynamics Of The Mental Workspace, Alexander Schlegel, Peter J. Kohler, Sergei V. Fogelson, Prescott Alexander

Dartmouth Scholarship

The conscious manipulation of mental representations is central to many creative and uniquely human abilities. How does the human brain mediate such flexible mental operations? Here, multivariate pattern analysis of functional MRI data reveals a widespread neural network that performs specific mental manipulations on the contents of visual imagery. Evolving patterns of neural activity within this mental workspace track the sequence of informational transformations carried out by these manipulations. The network switches between distinct connectivity profiles as representations are maintained or manipulated.

The Flexible Fairness: Equality, Earned Entitlement, And Self-Interest, Chunliang Feng, Yi Luo, Ruolei Gu, Lucas S. Broster, Xueyi Shen, Tengxiang Tian, Yue-Jia Luo, Frank Krueger

Behavioral Science Faculty Publications

The current study explored whether earned entitlement modulated the perception of fairness in three experiments. A preliminary resource earning task was added before players decided how to allocate the resource they jointly earned. Participants' decision in allocation, their responses to equal or unequal offers, whether advantageous or disadvantageous, and subjective ratings of fairness were all assessed in the current study. Behavioral results revealed that participants proposed more generous offers and showed enhanced tolerance to disadvantageous unequal offers from others when they performed worse than their presumed "partners," while the reverse was true in the better-performance condition. The subjective ratings also …

Unconscious Priming Requires Early Visual Cortex At Specific Temporal Phases Of Processing, Marjan Persuh, Tony Ro

Publications and Research

Although examples of unconscious shape priming have been well documented, whether such priming requires early visual cortex (V1/V2) has not been established. In the current study, we used TMS of V1/V2 at varying temporal intervals to suppress the visibility of preceding shape primes while the interval between primes and targets was kept constant. Our results show that, although conscious perception requires V1/V2, unconscious priming can occur without V1/V2 at an intermediate temporal interval but not at early (5–25 msec) or later (65–125 msec) stages of processing. Because the later time window of unconscious priming suppression has been proposed to interfere …

Neural Circuits Involved In Mental Arithmetic: Evidence From Customized Arithmetic Training, Christian Battista

Electronic Thesis and Dissertation Repository

An arithmetic training study was conducted using a novel paradigm known as Customized Arithmetic Training (CAT). Using the CAT system, self-reports obtained from the participants were used to generate individually tailored problem sets. These problem sets balanced strategy use such that each participant started with an equal amount of problems solved by fact retrieval (e.g., 2 + 2 = 4) and an equal amount of problems solved by procedural calculation (e.g., 34 + 37). Following the training period, participants solved trained and untrained problems from their customized arithmetic sets while undergoing an fMRI scan, after which they again provided self-reported …

A P300 Based Cognitive Assessment Battery For Severely Motor-Impaired And Overtly Non-Responsive Patients, Aaron M. Kirschner

Electronic Thesis and Dissertation Repository

Diagnosing disorders of consciousness (DOC) is notoriously difficult, with estimates of misdiagnosis rates as high as 40%. Moreover, recent studies have demonstrated that patients who do not show signs of volitional motor responses can exhibit preserved command following detected by functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). Although these patients clearly retain some cognitive abilities, lack of consistent motor responses makes administration of standard neuropsychological tests impossible. Consequently, the extent of their cognitive function is unknown. In the current study, we developed and validated a P300b event related potential (ERP) neuropsychological battery in healthy participants to assess components of …

Toxin-Induced Gustatory Conditioning In Rats: Examining The Effects Of Low Dose Toxins In Food On Rat Feeding Behaviour And Avoidance Conditioning, Amber N. Good

Electronic Thesis and Dissertation Repository

Foraging animals must learn which foods in their environment will maximize their nutritional needs but minimize the amount of ingested toxins. These animals rely on the integration of sensory and gustatory information and post-ingestive feedback from the foods they consume. Gustatory conditioning can be studied by using the conditioned taste avoidance paradigm and the toxin LiCl. This thesis first examined the dose related effects of low levels of LiCl on the ingestion of different palatable sucrose and salt solutions. The present findings support the hypothesis that rats use a behavioural tolerance mechanism to regulate their intake of foods containing low …

Network Dynamics Of Visual Naming, Christopher R. Conner

Dissertations & 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 …

The Influence Of Proficiency And Age Of Acquisition On Second Language Processing: An Fmri Study Of Mandarin-English Bilinguals, Emily S. Nichols

Electronic Thesis and Dissertation Repository

Research investigating the neural correlates of second language (L2) processing has usually studied age of acquisition (AoA) and proficiency separately. Presently, we examined both in parallel, treated as continuous variables. We used fMRI to study neural activity for L2 processing in adult native Mandarin speakers who are L2 English speakers. Behavioral measures of language proficiency and AoA were obtained from subjects prior to performing a picture-word matching task during an fMRI scan. Brain activity during L2 English processing was shown to be independently affected by AoA and proficiency; activity in left superior temporal gyrus and right parahippocampal gyrus was modulated …

What Can The Organization Of The Brain’S Default Mode Network Tell Us About Self-Knowledge?, Joseph. M. Moran, William M. Kelley, Todd F. Heatherton

Dartmouth Scholarship

Understanding ourselves has been a fundamental topic for psychologists and philosophers alike. In this paper we review the evidence linking specific brain structures to self-reflection. The brain regions most associated with self-reflection are the posterior cingulate and medial prefrontal (mPFC) cortices, together known as the cortical midline structures (CMSs). We review evidence arguing that self-reflection is special in memory, while noting that these brain regions are often engaged when we think about others in our social worlds. Based on the CMSs’ patterns of connectivity and activity, we speculate about three possible interpretations of their role in supporting self-reflection that are …

Decades-Long Social Memory In Bottlenose Dolphins, Jason N. Bruck

Faculty Publications

Long-term social memory is important, because it is an ecologically relevant test of cognitive capacity, it helps us understand which social relationships are remembered and it relates two seemingly disparate disciplines: cognition and sociality. For dolphins, long-term memory for conspecifics could help assess social threats as well as potential social or hunting alliances in a very fluid and complex fission-fusion social system, yet we have no idea how long dolphins can remember each other. Through a playback study conducted within a multi-institution dolphin breeding consortium (where animals are moved between different facilities), recognition of unfamiliar versus familiar signature whistles of …

Flexibly Adapting To Emotional Cues: Examining The Functional And Structural Correlates Of Emotional Reactivity And Emotion Control In Healthy And Depressed Individuals, Steven G. Greening

Electronic Thesis and Dissertation Repository

The ability of emotionally significant stimuli to bias our behaviour is an evolutionarily adaptive phenomenon. However, sometimes emotions become excessive, inappropriate, and even pathological, like in major depressive disorder (MDD). Emotional flexibility includes both the neural processes involved in reacting to, or representing, emotional significance, and those involved in controlling emotional reactivity. MDD represents a potentially distinct form of emotion (in)flexibility, and therefore offers a unique perspective for understanding both the integration of conflicting emotional cues and the neural regions involved in actively controlling emotional systems.

The present investigation of emotional flexibility began by considering the functional neural correlates of …

Targeted Training Of The Decision Rule Benefits Rule-Guided Behavior In Parkinson’S Disease, Shawn W. Ell

Psychology Faculty Scholarship

The impact of Parkinson’s disease (PD) on rule-guided behavior has received considerable attention in cognitive neuroscience. The majority of research has used PD as a model of dysfunction in fronto-striatal networks, but very few attempts have been made to investigate the possibility of adapting common experimental techniques in an effort to identify the conditions that are most likely to facilitate successful performance. The present study investigated a targeted training paradigm designed to facilitate rule learning and application using rule-based categorization as a model task. Participants received targeted training in which there was no selective-attention demand (i.e., stimuli varied along a …

The Effects Of Pedagogical Conditions On Second Language Acquisition, Mccall Evonne Sarrett

Chancellor’s Honors Program Projects

No abstract provided.

Evaluation Of A Short-Form Of The Berg Card Sorting Test, Christopher J. Fox, Shane T. Mueller, Hilary M. Gray, Jacob Raber, Brian J. Piper

Psychology Faculty Publications and Presentations

The Psychology Experimental Building Language http://pebl.sourceforge.net/Berg Card Sorting Test is an open-source neurobehavioral test. Participants (N = 207, ages 6 to 74) completed the Berg Card Sorting Test. Performance on the first 64 trials were isolated and compared to that on the full-length (128 trials) test. Strong correlations between the short and long forms (total errors: r = .87, perseverative response: r = .83, perseverative errors r = .77, categories completed r = .86) support the Berg Card Sorting Test-64 as an abbreviated alternative for the full-length executive function test.

Getting A Grip On Memory: Unilateral Hand Clenching Alters Episodic Recall, Ruth E. Propper, Sean E. Mcgraw, Tad T. Brunyé

Department of Psychology Faculty Scholarship and Creative Works

Unilateral hand clenching increases neuronal activity in the frontal lobe of the contralateral hemisphere. Such hand clenching is also associated with increased experiencing a given hemisphere’s “mode of processing.” Together, these findings suggest that unilateral hand clenching can be used to test hypotheses concerning the specializations of the cerebral hemispheres during memory encoding and retrieval. We investigated this possibility by testing the effects of a unilateral hand clenching on episodic memory. The hemispheric Encoding/Retrieval Asymmetry (HERA) model proposes left prefrontal regions are associated with encoding, and right prefrontal regions with retrieval, of episodic memories. It was hypothesized that right-hand clenching …

Research Brief: "Cognitive Behavioral Treatment For Post-Traumatic Nightmares: An Investigation Of Predictors Of Dropout And Outcome", Institute For Veterans And Military Families At Syracuse University

Institute for Veterans and Military Families

This brief is about the cognitive behavior treatment outcomes and drop outs of Vietnam veterans with PTSD who experience nightmares. In policy and practice, various socialization strategies should be implemented by clinics based on veterans' levels of traumatic history, and veterans' families should work to create a positive view of therapy; policymakers should provide support for these therapies and the training of clinicians to provide them. Suggestions for future research include having a more generalizable population in the study, examining the impact of the study's exclusion criteria, and the impact of psychotropic medicines on treatment outcome.

Interactions Between Lexical And Syntactic Knowledge During Incremental Processing Of The Causative Construction In English, G. Taylor Brooks

Georgia State Undergraduate Research Conference

No abstract provided.

Exploring The Neural Basis Of Top-Down Guided Action In Macaque Monkeys, Jessica M. Phillips

Electronic Thesis and Dissertation Repository

To thoroughly characterize any brain mechanism requires an appropriate animal model for invasive studies. An invaluable model system used toward a comprehension of cognitive neurophysiology is the macaque monkey. It is important to delineate similarities and limitations for this model in relation to the human brain and cognition. In this thesis, we have thus conducted three experiments to investigate putative generalizations between monkeys and humans regarding the neural processes associated with top-down action control in monkeys.

Our daily behaviour is largely comprised of automatic routine actions. The frequent repetition of certain behaviours in response to particular contexts can give rise …

Unconscious Processing Of Unattended Features In Human Visual Cortex, Tatiana Aloi Emmanouil, Philip Burton, Tony Ro

Publications and Research

Unconscious processing has been convincingly demonstrated for task-relevant feature dimensions. However, it is possible that the visual system is capable of more complex unconscious operations, extracting visual features even when they are unattended and task irrelevant. In the current study, we addressed this question by measuring unconscious priming using a task in which human participants attended to a target object's shape while ignoring its color. We measured both behavioral priming effects and priming-related fMRI activations from primes that were unconsciously presented using metacontrast masking. The results showed faster RTs and decreases in fMRI activation only when the primes were identical …

You, Your Neurons, And Free Will: Concerns About Reductionism And The Popularization Of Cognitive Science, Karl G. D. Bailey

Faculty Publications

No abstract provided.

Changes In Sleep Architecture And Cognition With Age And Psychosocial Stress: A Study In Fischer 344 Rats, Heather M. Buechel

Theses and Dissertations--Pharmacology and Nutritional Sciences

Changes in both sleep architecture and cognition are common with age. Typically these changes have a negative connotation: sleep fragmentation, insomnia, and deep sleep loss as well as forgetfulness, lack of focus, and even dementia and Alzheimer’s disease. Research has shown that psychosocial stressors, such as isolation from family and friends or loss of a loved one can also have significant negative effects on sleep architecture and cognitive capabilities. This leaves the elderly in a particularly vulnerable situation: suffering from cognitive decline and sleep dysregulation already, and more likely to respond negatively to psychosocial stressors. Taking all of these factors …

Brain Activity Follow Up Of Stock Market Financial Variables, Armando F. Rocha, João Vieito, Fábio T. Rocha

Armando F Rocha

Efficiency Market hypothesis assume that all investors reason in the same way to make their financial decisions. In contrast, Neurosciences have provided strong evidences that cognitive diversity is the hallmark of human intelligence. Neurofinances has shown that volunteers learned different profitable financial decision-making strategies depending on the kind of market they begun to trade. Here, we decide to further explore this hypothesis by studying a possible correlation between brain activity and the financial variables in a stock market game and to test if this correlation differ between experimental groups that trade in different market conditions. Present results show that volunteers …

You, Your Neurons, And Free Will: Concerns About Reductionism And The Popularization Of Cognitive Science, Karl G. D. Bailey

Karl Bailey

No abstract provided.

Doxorubicin-Induced, Tnf-Α-Mediated Brain Oxidative Stress, Neurochemical Alterations, And Cognitive Decline: Insights Into Mechanisms Of Chemotherapy Induced Cognitive Impairment And Its Prevention, Jeriel T. Keeney

Theses and Dissertations--Chemistry

The works presented in this dissertation provide insights into the mechanisms of chemotherapy-induced cognitive impairment (CICI or “ChemoBrain”) and take steps toward outlining a preventive strategy. CICI is now widely recognized as a complication of cancer chemotherapy experienced by a large percentage of cancer survivors. Approximately fifty percent of existing FDA-approved anti-cancer drugs generate reactive oxygen species (ROS). Doxorubicin (Dox), a prototypical ROS-generating chemotherapeutic agent, produces the reactive superoxide radical anion (O₂^-•) in vivo. Dox treatment results in oxidation of plasma proteins, including ApoA-I, leading to TNF-α-mediated oxidative stress in plasma and brain. TNF-α elevation in brain …

Does Experience In Talking Facilitate Speech Repetition?, Linda Shuster, Donna Moore, Gang Chen, Dennis Ruscello, William Wonderlin

Linda Shuster

No abstract provided.