Cognitive Neuroscience Commons^™

Neurobehavioral Mechanisms Of Psychotic-Like Experiences And Cannabis Use, Ethan Campbell

Psychology ETDs

As cannabis use has increased steadily over the past decade, there is critical need to evaluate early cannabis use as a potential risk factor for the development of psychosis. Neurobehavioral mechanisms underlying novelty salience could clarify how cannabis exposure may influence subclinical psychotic-like experiences (PLEs). The present study leveraged dynamic functional connectivity and task-fMRI to assess the role of novelty processing in cannabis use and PLEs. A group of brain regions dynamically tied to the salience network while viewing short films were found to increase their activation as a function of stimulus novelty during a novelty bandit task. PLEs were …

Neural Patterns Reflect Semantic Representation In Novice Sign Language Learners, Megan E. Hillis

Dartmouth College Ph.D Dissertations

How do novice language learners represent semantic information in their new language? The extent to which languages are supported by distinct or overlapping neural representations in bilinguals has been the topic of much research, but less is known about how new knowledge is integrated into established representational networks, especially at the earliest stages of language acquisition. Furthermore, most investigations have compared languages which share a modality (spoken). Signed languages can provide insight into language unconfounded by perceptual qualities that spoken languages share. Chapter 1 presents an initial study in which hearing English-speaking non-signers learned a set of nouns in American …

The Effect Of Repetitive Transcranial Magnetic Stimulation On Brain And Cognitive Variables In Patients With Amnestic Mild Cognitive Impairment, Connor J. Phipps

Theses & Dissertations

Healthy and pathological aging processes can impact human memory. Current interventions for clinical memory impairment offer little opportunity for restoration of memory ability. Fortunately, a novel therapy in the form of repetitive transcranial magnetic stimulation (rTMS) has exhibited promise in this regard. In healthy adults, rTMS of the angular gyrus (AG) has been reported to improve memory. The current study sought to determine the generalizability of these findings to individuals with clinical memory impairment by administering a clinical trial replicating an rTMS protocol reported to improve hippocampal-dependent memory in healthy individuals to individuals with amnestic mild cognitive impairment (aMCI). Individuals …

Target Selection And Enhancement During Attentional Tracking, Marvin R. Maechler

Dartmouth College Ph.D Dissertations

At any waking moment, we are bombarded with more sensory information than we can fully process. Attention is necessary to deal with the dynamic world we live in. One fundamental function of vision and attention is to keep track of moving objects, but what are the targets of attention during tracking?

One of the first theories of attentional tracking predicted that targets would be selected at early processing stages. By employing the double-drift illusion, which dissociates physical and perceived positions of moving objects, we investigated which of these positions is selected for tracking. Contrary to earlier theories and in line …

The Neural Sequalae Of Subjectively Experiencing Autobiographical Memories From The Remote Past And Recent Present Using Fmri, Ava G. Peruski, Nim Singh, Brendan E. Depue

The Cardinal Edge

Autobiographical memory is central to one's sense of self and continuity from past to present. Despite this, there is little research on the neural correlates underlying individual subjective experience of autobiographical memory and how that is related to brain phenomena (i.e., activity, communication). The purpose of this study was to help minimize this gap. We recruited twenty healthy adult participants, who were asked to generate memory cues (1-3 word descriptions) for locations and objects from their early and recent life. After 24 hours, participants were shown these cues then asked to recall the appropriate memory while in an fMRI scanner. …

Attenuated Typicality Effect In Category-Based Inferences: Implications For Autism Spectrum Disorder, Janani Rajagopalan

Dissertations, Theses, and Capstone Projects

Individuals diagnosed with Autism Spectrum Disorder (ASD) often encounter challenges in assimilating atypical exemplars into their categorical prototypes, a cognitive hurdle that can impact their interpretative and integrative capacities. Addressing this problem, the present research sought to develop a robust methodological approach to reduce the effect of this disparity. We examined the elements embedded within the category's internal structure, with the intention of experimentally attenuating the pronounced typicality effect, which is often exaggerated in ASD.

Across four experiments, the thesis investigated the cognitive and neural underpinnings that shape the access to the typicality gradient intrinsic to a category's structure. The …

To Laugh Or Not To Laugh: That Is The Question Of Humor Techniques And Sex Differences, Yu-Chen Chan

Journal of Educational Technology Development and Exchange (JETDE)

A humor structure comprises two essential stages: the setup and the punch line. The punch line stage is to provide the incongruity resolution that creates amusement in humor. The current article aimed to look into how humor is amusing and how it differs between the sexes. Functional and effective connectivity analyses in cognitive and affective neuroscience have facilitated the implications of humor comprehension, appreciation, and laughter responses. The processing of incongruity-resolution humor revealed effective connectivity from the amygdala to the precuneus (amygdala → precuneus). Conversely, the processing of nonsense humor demonstrated effective connectivity from the amygdala to the inferior frontal …

Neural Systems Underlying Rdoc Social Constructs: An Activation Likelihood Estimation Meta-Analysis, Rosario Pintos Lobo, Katherine L. Bottenhorn, Michael C. Riedel, Afra I. Toma, Megan M. Hare, Donisha D. Smith, Alexandra C. Moor, Isis K. Cowan, Javier A. Valdes, Jessica E. Bartley, Taylor Salo, Emily R. Boeving, Brianna Pankey, Matthew T. Sutherland, Erica D. Musser, Angela R. Laird

Psychology Faculty Publications

Neuroscientists have sought to identify the underlying neural systems supporting social processing that allow interaction and communication, forming social relationships, and navigating the social world. Through the use of NIMH’s Research Domain Criteria (RDoC) framework, we evaluated consensus among studies that examined brain activity during social tasks to elucidate regions comprising the “social brain”. We examined convergence across tasks corresponding to the four RDoC social constructs, including Affiliation and Attachment, Social Communication, Perception and Understanding of Self, and Perception and Understanding of Others. We performed a series of coordinate-based meta-analyses using the activation likelihood estimate (ALE) method. Meta-analysis was performed …

Causal Inference In Psychology And Neuroscience: From Association To Causation, Dehua Liang

Computational and Data Sciences (PhD) Dissertations

In psychology and neuroscience, inferring causality in non-experimental studies is almost taboo, because data in these studies, e.g., survey data and resting-state neuroimaging data, are often contaminated by unmeasured confounders. Psychologists and neuroscientists are often cautious about their results, and reluctant to make false claims about causality in non-experimental studies. Therefore, they adopt less stringent statistical analysis techniques that can only infer associational relations. However, the ambiguity about causality in traditional statistical analysis creates much confusion in interpreting analytical results - some studies make implicit causal claims about their results using words such as “impacts”, “lead to” and “affects”. This …

Cerebellum-Seeded Functional Connectivity Changes In Trait-Anxious Individuals Undergoing Attention Bias Modification Training, Katherine Elwell

All NMU Master's Theses

Anxiety and anxiety related disorders are increasing at a drastic rate in the past decade, with the NIMH reporting that 31.1% of U.S. adults will experience an anxiety disorder at some point in their lives. Anxiety is commonly characterized by increased attention bias to threat. Attention Bias Modification (ABM) is a new treatment used to reduce individual’s attention bias towards threat. The extent to which ABM leads to underlying neural changes is still unknown. The cerebellum is a neglected brain structure, with new research provides evidence that cerebellum’s functional connectivity and shared networks with threat processing regions has a direct …

Cortical Dynamics Of Language, Kiefer Forseth

Dissertations and Theses (Open Access)

The human capability for fluent speech profoundly directs inter-personal communication and, by extension, self-expression. Language is lost in millions of people each year due to trauma, stroke, neurodegeneration, and neoplasms with devastating impact to social interaction and quality of life. The following investigations were designed to elucidate the neurobiological foundation of speech production, building towards a universal cognitive model of language in the brain. Understanding the dynamical mechanisms supporting cortical network behavior will significantly advance the understanding of how both focal and disconnection injuries yield neurological deficits, informing the development of therapeutic approaches.

Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt

Publications and Research

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation approach in which low level currents are administered over the scalp to influence underlying brain function. Prevailing theories of tDCS focus on modulation of excitation-inhibition balance at the local stimulation location. However, network level effects are reported as well, and appear to depend upon differential underlying mechanisms. Here, we evaluated potential network-level effects of tDCS during the Serial Reaction Time Task (SRTT) using convergent EEG- and fMRI-based connectivity approaches. Motor learning manifested as a significant (p <.0001) shift from slow to fast responses and corresponded to a significant increase in beta-coherence (p <.0001) and fMRI connectivity (p <.01) particularly within the visual-motor pathway. Differential patterns of tDCS effect were observed within different parametric task versions, consistent with network models. Overall, these findings demonstrate objective physiological effects of tDCS at the network level that result in effective behavioral modulation when tDCS parameters are matched to network-level requirements of the underlying task.

Multimodal Computational Modeling Of Visual Object Recognition Deficits But Intact Repetition Priming In Schizophrenia, Pejman Sehatpour, Anahita Bassir Nia, Devin Adair, Zhishun Wang, Heloise M. Debaun, Gail Silipo, Antigona Martinez, Daniel C. Javitt

Publications and Research

The term perceptual closure refers to the neural processes responsible for “filling-in” missing information in the visual image under highly adverse viewing conditions such as fog or camouflage. Here we used a closure task that required the participants to identify barely recognizable fragmented line-drawings of common objects. Patients with schizophrenia have been shown to perform poorly on this task. Following priming, controls and importantly patients can complete the line-drawings at greater levels of fragmentation behaviorally, suggesting an improvement in their ability to performthe task. Closure phenomena have been shown to involve a distributed network of cortical regions, notably the lateral …

The Temporal Dynamics Of Ensemble Perception, Michael L. Epstein

Dissertations, Theses, and Capstone Projects

The striking disparity between the subjective richness of experience and the considerable limitations of perceptual processing has emerged as an essential, enduring question in both vision science and philosophy of mind. A potential solution to this issue is ensemble perception: the ability for the visual system to compute the statistical summaries of object groups, effectively compressing an otherwise overwhelming amount of information. Previous work has supported that ensemble statistics can be perceived quickly and accurately for a wide range of object features. This has motivated models of ensemble perception as an early process in vision, providing an initial sense of …

Changes In Hemodynamic Response To Faces, Scenes, And Objects In A Visual Statistical Learning Task: An Fmri Analysis, Aaron T. Halvorsen

Honors Program: Senior Projects (Public)

Learning causes changes in brain activity and neural connections. Statistical learning is an implicit learning process that involves extracting regularities from the environment and finding patterns in stimuli based on their transitional probabilities. The following study describes an attempt to elucidate temporal changes in hemodynamic activity for three category-specific brain areas using functional magnetic resonance imaging (fMRI). Blood oxygen-level dependent signal (BOLD) responses were collected while subjects viewed faces, scenes, and objects with high and low transitional probabilities in an fMRI scanner. We expected brain activity to show a temporal shift in timing of activation when comparing BOLD signal responses …

Variance Partitioning Reveals Consistent Representation Of Object Boundary Contours In Lo Across Different Datasets, Mark D. Lescroart, Utkarsh Singhal

MODVIS Workshop

No abstract provided.

The Generalization Of Fear Condition Between Viewed And Imagined Percepts, Lauryn Michelle Burleigh

LSU Master's Theses

Mental images can provoke intense emotional states (Holmes & Matthews, 2010). Imagery and perception have common neural and physiological mechanisms, including activation of the early visual areas (Albers et al., 2013). We tested the prediction that individuals can acquire fear to imagined percepts and if this fear transfers to viewing percepts, using fMRI and self-reported measures to determine participants’ fear. The participants completed a task in which they viewed and imagined two stimuli, and were fear conditioned when imagining the CS+. Participants are only told that mild electrical stimulation will be paired with one of the stimuli, but not which …

The Relationship Between Cognitive And Neural Bases Of Metamemory Judgments, Alexandra M. Gaynor

Dissertations, Theses, and Capstone Projects

Metamemory monitoring, the process of making subjective assessments of the status of one’s own memory, is crucial to guiding behavior and effective learning. Past cognitive research has shown that subjective confidence judgments are inferential in nature, and based on cues available at the time of the judgment. When confidence is based on cues that are related to objective memory performance, metamemory accuracy is high. However, past studies have shown that metamemory monitoring tends to be inaccurate because individuals base their confidence on information that is not predictive of memory success, such as the fluency with which items were encoded during …

Neural Correlates Of Polysubstance Use: Differential And Interactive Effects Of Alcohol And Cannabis On The Adolescent Brain, Joseph Aloi

Theses & Dissertations

Two of the most commonly used and abused substances by adolescents in the United States are alcohol and cannabis, which are associated with adverse medical and psychiatric outcomes. Alcohol use and cannabis use during adolescence is also associated with an increased risk of alcohol use disorder (AUD) and/or cannabis use disorder (CUD) in adulthood as well as increased likelihood of relapse after successful treatment. Despite this, much of the previous work on the neurobiology of substance use disorders has focused on adult substance use. This work has shown that individuals with AUD and/or CUD show dysfunction within reward processing, emotion …

When Less Is More: Mindfulness Predicts Adaptive Affective Responding To Rejection Via Reduced Prefrontal Recruitment, Alexandra M. Martelli, David S. Chester, Kirk Warren Brown, Naomi I. Eisenberger, C. Nathan Dewall

Psychology Faculty Publications

Social rejection is a distressing and painful event that many people must cope with on a frequent basis. Mindfulness—defined here as a mental state of receptive attentiveness to internal and external stimuli as they arise, moment-to-moment—may buffer such social distress. However, little research indicates whether mindful individuals adaptively regulate the distress of rejection—or the neural mechanisms underlying this potential capacity. To fill these gaps in the literature, participants reported their trait mindfulness and then completed a social rejection paradigm (Cyberball) while undergoing functional magnetic resonance imaging. Approximately 1 hour after the rejection incident, participants reported their level of distress during …

Jealousy, Competition, Or A Contextual Cue For Reward?, Thomas R. Zentall

Animal Sentience

Emotions are difficult to assess, even in humans. The attribution of jealousy in an animal like a dog is especially difficult because performance of a particular behavior in the context of another animal receiving a reward may not be easily distinguishable from intra-species competition or simply a response to a contextual cue for the availability of reward. The authors provide distinguishing evidence in the form of fMRI data to show that in the presence of a “fake” dog being fed, there is bilateral activation in the amygdala, an area associated with anxiety, anger, fear, and even jealousy in humans.

Dynamic Range Of Frontoparietal Functional Modulation Is Associated With Working Memory Capacity Limitations In Older Adults, Jonathan G. Hakun, Nathan F. Johnson

Physical Therapy Faculty Publications

Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60–77 years of age), age was negatively associated with frontoparietal modulation range. …

Combined Mnemonic Strategy Training And High-Definition Transcranial Direct Current Stimulation For Memory Deficits In Mild Cognitive Impairment, Benjamin M. Hampstead, Krishnankutty Sathian, Marom Bikson, Anthony Y. Stringer

Publications and Research

Introduction: Memory deficits characterize Alzheimer’s dementia and the clinical precursor stage known as mild cognitive impairment. Nonpharmacologic interventions hold promise for enhancing functioning in these patients, potentially delaying functional impairment that denotes transition to dementia. Previous findings revealed that mnemonic strategy training (MST) enhances long-term retention of trained stimuli and is accompanied by increased blood oxygen level–dependent signal in the lateral frontal and parietal cortices as well as in the hippocampus. The present study was designed to enhance MST generalization, and the range of patients who benefit, via concurrent delivery of transcranial direct current stimulation (tDCS).

Methods: This protocol describes …

Mapping The Spatio-Temporal Dynamics Of Vision In The Human Brain, Aude Oliva

MODVIS Workshop

Recognition of objects and scenes is a fundamental function of the human brain, necessitating a complex neural machinery that transforms low level visual information into semantic content. Despite significant advances in characterizing the locus and function of key visual areas, integrating the temporal and spatial dynamics of this processing stream has posed a decades-long challenge to human neuroscience. In this talk I will describe a brain mapping approach to combine magnetoencephalography (MEG), functional MRI (fMRI) measurements, and convolutional neural networks (CNN) by representational similarity analysis to yield a spatially and temporally integrated characterization of neuronal representations when observers perceive visual …

Functional Neural Connectivity Associated With Moral Processing In Healthy And Antisocial Samples, Samantha Jean Fede

Psychology ETDs

Although research finds that brain abnormalities during moral decisions underlie traits that lead to crime, understanding of these neural dynamics is limited. Here we use two samples to explore the role network engagement and components during moral processing. We used independent component analysis and functional network connectivity analysis to examine hemodynamic response during an fMRI task of moral processing. Eighty-four community and 539 incarcerated adult men and women participated; MANCOVA and machine learning algorithms were used to identify individual and group differences in both samples. We found patterns of neural engagement and connectivity consistent with proposed models of moral cognition …

Relationship Between Structure And Functional Connectivity Within The Default Mode Network, Andrei A. Vakhtin

Psychology ETDs

We proposed a novel measure of conceptualizing dynamic functional network connectivity (FNC) in the human brain using flexibility of functional connectivity (fFC), which captures the variance of functional connectivity across time. In task-free fMRI scans (N = 122), this measure was demonstrated to correspond to the underlying structural connectivity (SC) within the default mode network (DMN), while static functional connectivity (sFC) did so to a relatively low degree. As SC likely does not develop to facilitate task-free brain function, but rather to integrate information during cognitive engagement, we argue that fFC can estimate the potential functional connectivity exhibited outside of …

Does The Pain Of Rejection Promote The Pleasure Of Revenge? A Neural Investigation Of Cingulo-Striatal Contributions To Violence, David Chester

Theses and Dissertations--Psychology

Aggression is a dynamic and costly feature of human behavior. One reliable cause of aggression is social rejection, though the underlying mechanisms of this effect remain to be fully understood. Previous research has identified two psychological processes that are independently linked to aggressive retaliation: pain and pleasure. Given recent findings that pain magnifies the experience of pleasure, I predicted that the pain of rejection would promote the pleasure of aggression and thus, aggression itself. I also expected that this indirect effect of aggressive pleasure would only be observed among individuals with weaker self-regulatory abilities that are necessary to cope with …

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), …

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 …

Increased Modulation By Cognitive Control Region During Fmri Working Memory Task Suggest Inefficiencies In Network Connectivity In Children With Adhd, Ashley Burgess

Honors College Theses

Attention Deficit / Hyperactivity Disorder is a neurodevelopmental disorder common among children and adolescent populations whose symptoms are believed to be caused by deficits in executive functioning processes such as working memory. Using fMRI analyses, differences in the modulatory influence exhibited by the dorsal anterior cingulate cortex (dACC) on cortico-striatal regions implicated in working memory (2-back) (Owen et al 2005) was assessed between children with ADHD (twenty-three participants; mean age 6 yrs: 6.4-14.9 yrs) and healthy controls (twenty-six participants; mean age 10.1yrs: 6.3-14.1 yrs). Modulatory influence is defined as the degree to which one region exerts control on another region …