Cognition and Perception Commons^™

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 …

Investigating The Roles Of The Dorsal And Ventral Striatum In Humor Comprehension And Appreciation Throughout Health, Aging, And Parkinson’S Disease, Maggie Prenger

Electronic Thesis and Dissertation Repository

Humor processing is thought to involve two distinct components. The first, humor comprehension, involves detecting and resolving incongruities that are present within a humorous stimulus. This is related to cognitive processes such as ambiguity resolution, response inhibition, working memory, and cognitive flexibility, functions that are mediated in part by the dorsal portion of the striatum (DS). Humor appreciation, on the other hand, refers to the subjective amusement and mirth that one experiences in response to a joke. This is related to reward processing, which implicates the ventral portion of the striatum (VS). Across three separate studies, we investigated the involvement …

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 Theses

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 …

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 …

A Combined Fmri And Dti Examination Of Functional Language Lateralization And Arcuate Fasciculus Structure: Effects Of Degree Versus Direction Of Hand Preference Author Links Open Overlay Panel, Ruth E. Propper, Lauren J. O'Donnell, Stephen Whalen, Yanmei Tie, Isaiah Norton, Ralph O. Suarez, Lilla Zollei, Alireza Radmanesh, Alexandra Golby

Ruth Propper

The present study examined the relationship between hand preference degree and direction, functional language lateralization in Broca’s and Wernicke’s areas, and structural measures of the arcuate fasciculus. Results revealed an effect of degree of hand preference on arcuate fasciculus structure, such that consistently-handed individuals, regardless of the direction of hand preference, demonstrated the most asymmetric arcuate fasciculus, with larger left versus right arcuate, as measured by DTI. Functional language lateralization in Wernicke’s area, measured via fMRI, was related to arcuate fasciculus volume in consistent-left-handers only, and only in people who were not right hemisphere lateralized for language; given the …

Exploring The Neural Mechanisms Of Physics Learning, Jessica E. Bartley

FIU Electronic Theses and Dissertations

This dissertation presents a series of neuroimaging investigations and achievements that strive to deepen and broaden our understanding of human problem solving and physics learning. Neuroscience conceives of dynamic relationships between behavior, experience, and brain structure and function, but how neural changes enable human learning across classroom instruction remains an open question. At the same time, physics is a challenging area of study in which introductory students regularly struggle to achieve success across university instruction. Research and initiatives in neuroeducation promise a new understanding into the interactions between biology and education, including the neural mechanisms of learning and development. These …

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.

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 …

How Should Justice Policy Treat Young Offenders?, B J. Casey, Richard J. Bonnie, Andre Davis, David L. Faigman, Morris B. Hoffman, Owen D. Jones, Read Montague, Stephen J. Morse, Marcus E. Raichle, Jennifer A. Richeson, Elizabeth S. Scott, Laurence Steinberg, Kim A. Taylor-Thompson, Anthony D. Wagner

All Faculty Scholarship

The justice system in the United States has long recognized that juvenile offenders are not the same as adults, and has tried to incorporate those differences into law and policy. But only in recent decades have behavioral scientists and neuroscientists, along with policymakers, looked rigorously at developmental differences, seeking answers to two overarching questions: Are young offenders, purely by virtue of their immaturity, different from older individuals who commit crimes? And, if they are, how should justice policy take this into account?

A growing body of research on adolescent development now confirms that teenagers are indeed inherently different from adults, …

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 …

Mental Blocks: The Behavioural Effects And Neural Encoding Of Obstacles When Reaching And Grasping, Craig S. Chapman

Electronic Thesis and Dissertation Repository

The ability to adeptly interact with a cluttered and dynamic world requires that the brain simultaneously encode multiple objects. Theoretical frameworks of selective visuomotor attention provide evidence for parallel encoding (Baldauf & Deubel, 2010; Cisek & Kalaska, 2010; Duncan, 2006) where concurrent object processing results in neural competition. Since the end goal of object representation is usually action, these frameworks argue that the competitive activity is best characterized as the development of visuomotor biases. While some behavioural and neural evidence has been accumulated in favour of this explanation, one of the most striking, yet deceptively common, demonstrations of this capacity …

A Combined Fmri And Dti Examination Of Functional Language Lateralization And Arcuate Fasciculus Structure: Effects Of Degree Versus Direction Of Hand Preference Author Links Open Overlay Panel, Ruth E. Propper, Lauren J. O'Donnell, Stephen Whalen, Yanmei Tie, Isaiah Norton, Ralph O. Suarez, Lilla Zollei, Alireza Radmanesh, Alexandra Golby

Department of Psychology Faculty Scholarship and Creative Works

The present study examined the relationship between hand preference degree and direction, functional language lateralization in Broca’s and Wernicke’s areas, and structural measures of the arcuate fasciculus. Results revealed an effect of degree of hand preference on arcuate fasciculus structure, such that consistently-handed individuals, regardless of the direction of hand preference, demonstrated the most asymmetric arcuate fasciculus, with larger left versus right arcuate, as measured by DTI. Functional language lateralization in Wernicke’s area, measured via fMRI, was related to arcuate fasciculus volume in consistent-left-handers only, and only in people who were not right hemisphere lateralized for language; given the …