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Full-Text Articles in Social and Behavioral Sciences

Token Representation?: Impact Of Female Reservations In Panchayati Raj Institutions In Elections To State And National Legislatures, Surbhi Bharadwaj Sep 2019

Token Representation?: Impact Of Female Reservations In Panchayati Raj Institutions In Elections To State And National Legislatures, Surbhi Bharadwaj

Dartmouth Undergraduate Journal of Politics, Economics and World Affairs

Reservations have long formed a fundamental tenet of affirmative action in India. Quotas for representation of various disadvantaged groups proliferate across public educational institutions and government jobs. However, elections to public office have largely escaped such quotas, except those that are caste-based. A shift in this status quo occurred in 1992 with the establishment of the Panchayati Raj system of grassroots governance. 34% of all seats under Panchayati Raj Institutions (PRIs) were to be reserved for women under the 73rd amendment. Another constitutional amendment passed in September 2009 increased PRI quotas for women to 50%. This paper seeks to examine …


Re-Thinking Anxiety: Using Inoculation Messages To Reduce And Reinterpret Public Speaking Fears, Ben Jackson, Josh Compton, Ashleigh L. Thornton, James A. Dimmock Jan 2017

Re-Thinking Anxiety: Using Inoculation Messages To Reduce And Reinterpret Public Speaking Fears, Ben Jackson, Josh Compton, Ashleigh L. Thornton, James A. Dimmock

Dartmouth Scholarship

Inoculation theory offers a framework for protecting individuals against challenges to an existing attitude, belief, or state. Despite the prevalence and damaging effects of public speaking anxiety, inoculation strategies have yet to be used to help individuals remain calm before and during public speaking. We aimed to test the effectiveness of an inoculation message for reducing the onset of public speaking anxiety, and helping presenters interpret their speech-related anxiety more positively. Participants (Mage = 20.14, SD = 2.72) received either an inoculation (n = 102) or control (n = 128) message prior to engaging a public …


Your Teaching Strategy Matters: How Engagement Impacts Application In Health Information Literacy Instruction, Heather A. Johnson, Laura C. Barrett Jan 2017

Your Teaching Strategy Matters: How Engagement Impacts Application In Health Information Literacy Instruction, Heather A. Johnson, Laura C. Barrett

Dartmouth Scholarship

The purpose of this study was to compare two pedagogical methods, active learning and passive instruction, to determine which is more useful in helping students to achieve the learning outcomes in a one-hour research skills instructional session.


Is The Closest Facility The One Actually Used? An Assessment Of Travel Time Estimation Based On Mammography Facilities, Jennifer Alford-Teaster, Jane M. Lange, Rebecca A. Hubbard, Christoph I. Lee, Jennifer S. Haas, Xun Shi, Heather A. Carlos, Louise Henderson, Deirdre Hill, Anna N. A. Tosteson, Tracy Onega Feb 2016

Is The Closest Facility The One Actually Used? An Assessment Of Travel Time Estimation Based On Mammography Facilities, Jennifer Alford-Teaster, Jane M. Lange, Rebecca A. Hubbard, Christoph I. Lee, Jennifer S. Haas, Xun Shi, Heather A. Carlos, Louise Henderson, Deirdre Hill, Anna N. A. Tosteson, Tracy Onega

Dartmouth Scholarship

Characterizing geographic access depends on a broad range of methods available to researchers and the healthcare context to which the method is applied. Globally, travel time is one frequently used measure of geographic access with known limitations associated with data availability. Specifically, due to lack of available utilization data, many travel time studies assume that patients use the closest facility. To examine this assumption, an example using mammography screening data, which is considered a geographically abundant health care service in the United States, is explored. This work makes an important methodological contribution to measuring access--which is a critical component of …


Multimodal Frontostriatal Connectivity Underlies Individual Differences In Self-Esteem, Robert S. Chavez, Todd F. Heatherton May 2015

Multimodal Frontostriatal Connectivity Underlies Individual Differences In Self-Esteem, Robert S. Chavez, Todd F. Heatherton

Dartmouth Scholarship

A heightened sense of self-esteem is associated with a reduced risk for several types of affective and psychiatric disorders, including depression, anxiety and eating disorders. However, little is known about how brain systems integrate self-referential processing and positive evaluation to give rise to these feelings. To address this, we combined diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) to test how frontostriatal connectivity reflects long-term trait and short-term state aspects of self-esteem. Using DTI, we found individual variability in white matter structural integrity between the medial prefrontal cortex and the ventral striatum was related to trait measures of …


Preempting Performance Challenges: The Effects Of Inoculation Messaging On Attacks To Task Self-Efficacy, Ben Jackson, Josh Compton, Ryan Whiddett, David R. Anthony, James A. Dimmock Apr 2015

Preempting Performance Challenges: The Effects Of Inoculation Messaging On Attacks To Task Self-Efficacy, Ben Jackson, Josh Compton, Ryan Whiddett, David R. Anthony, James A. Dimmock

Dartmouth Scholarship

Although inoculation messages have been shown to be effective for inducing resistance to counter-attitudinal attacks, researchers have devoted relatively little attention toward studying the way in which inoculation theory principles might support challenges to psychological phenomena other than attitudes (e.g., self-efficacy). Prior to completing a physical (i.e., balance) task, undergraduates (N = 127, Mage = 19.20, SD = 2.16) were randomly assigned to receive either a control or inoculation message, and reported their confidence in their ability regarding the upcoming task. During the task, a confederate provided standardized negative feedback to all participants regarding their performance, and following …


Belief About Nicotine Selectively Modulates Value And Reward Prediction Error Signals In Smokers, Xiaosi Gu, Terry Lohrenz, Ramiro Salas, Philip R. Baldwin, Alireza Soltani Feb 2015

Belief About Nicotine Selectively Modulates Value And Reward Prediction Error Signals In Smokers, Xiaosi Gu, Terry Lohrenz, Ramiro Salas, Philip R. Baldwin, Alireza Soltani

Dartmouth Scholarship

Little is known about how prior beliefs impact biophysically described processes in the presence of neuroactive drugs, which presents a profound challenge to the understanding of the mechanisms and treatments of addiction. We engineered smokers' prior beliefs about the presence of nicotine in a cigarette smoked before a functional magnetic resonance imaging session where subjects carried out a sequential choice task. Using a model-based approach, we show that smokers' beliefs about nicotine specifically modulated learning signals (value and reward prediction error) defined by a computational model of mesolimbic dopamine systems. Belief of "no nicotine in cigarette" (compared with "nicotine in …


Launching A Virtual Decision Lab: Development And Field-Testing Of A Web-Based Patient Decision Support Research Platform, Aubri S. Hoffman, Hilary A. Llewellyn-Thomas, Anna N. A. Tosteson, Annette M. Oconnor Dec 2014

Launching A Virtual Decision Lab: Development And Field-Testing Of A Web-Based Patient Decision Support Research Platform, Aubri S. Hoffman, Hilary A. Llewellyn-Thomas, Anna N. A. Tosteson, Annette M. Oconnor

Dartmouth Scholarship

Over 100 trials show that patient decision aids effectively improve patients’ information comprehension and values-based decision making. However, gaps remain in our understanding of several fundamental and applied questions, particularly related to the design of interactive, personalized decision aids. This paper describes an interdisciplinary development process for, and early field testing of, a web-based patient decision support research platform, or virtual decision lab, to address these questions.


Naturally Occurring Peer Support Through Social Media: The Experiences Of Individuals With Severe Mental Illness Using Youtube, John A. Naslund, Stuart W. Grande, Kelly A. Aschbrenner, Glyn Elwyn Oct 2014

Naturally Occurring Peer Support Through Social Media: The Experiences Of Individuals With Severe Mental Illness Using Youtube, John A. Naslund, Stuart W. Grande, Kelly A. Aschbrenner, Glyn Elwyn

Dartmouth Scholarship

Increasingly, people with diverse health conditions turn to social media to share their illness experiences or seek advice from others with similar health concerns. This unstructured medium may represent a platform on which individuals with severe mental illness naturally provide and receive peer support. Peer support includes a system of mutual giving and receiving where individuals with severe mental illness can offer hope, companionship, and encouragement to others facing similar challenges. In this study we explore the phenomenon of individuals with severe mental illness uploading videos to YouTube, and posting and responding to comments as a form of naturally occurring …


The N400 As An Index Of Racial Stereotype Accessibility, Eric Hehman, Hannah I. Volpert, Robert F. Simons Mar 2014

The N400 As An Index Of Racial Stereotype Accessibility, Eric Hehman, Hannah I. Volpert, Robert F. Simons

Dartmouth Scholarship

The current research examined the viability of the N400, an event-related potential (ERP) related to the detection of semantic incongruity, as an index of both stereotype accessibility and interracial prejudice. Participants’ EEG was recorded while they completed a sequential priming task, in which negative or positive, stereotypically black (African American) or white (Caucasian American) traits followed the presentation of either a black or white face acting as a prime. ERP examination focused on the N400, but additionally examined N100 and P200 reactivity. Replicating and extending previous N400 stereotype research, results indicated that the N400 can indeed function as an index …


Investigating The Early Stages Of Person Perception: The Asymmetry Of Social Categorization By Sex Vs. Age, Jasmin Cloutier, Jonathan B. Freeman, Nalini Ambady Jan 2014

Investigating The Early Stages Of Person Perception: The Asymmetry Of Social Categorization By Sex Vs. Age, Jasmin Cloutier, Jonathan B. Freeman, Nalini Ambady

Dartmouth Scholarship

The wealth of information provided by facial cues presents challenges to our understanding of these early stages of person perception. The current study aimed to uncover the dynamics of processing multiply categorizable faces, notably as a function of their gender and age. Using a modified four-choice version of a mouse-tracking paradigm (which assesses the relative dominance of two categorical dimensions), the relative influence that sex and age have on each other during categorization of infant, younger adult, and older adult faces was investigated. Results of these experiments demonstrate that when sex and age dimensions are simultaneously categorized, only for infant …


Enrichment And Training Improve Cognition In Rats With Cortical Malformations, Kyle R. Jenks, Marcella M. Lucas, Ben A. Duffy, Ashlee A. Robbins, Barjor Gimi, Jeremy M. Barry, Rod C. Scott Dec 2013

Enrichment And Training Improve Cognition In Rats With Cortical Malformations, Kyle R. Jenks, Marcella M. Lucas, Ben A. Duffy, Ashlee A. Robbins, Barjor Gimi, Jeremy M. Barry, Rod C. Scott

Dartmouth Scholarship

Children with malformations of cortical development (MCD) frequently have associated cognitive impairments which reduce quality of life. We hypothesized that cognitive deficits associated with MCD can be improved with environmental manipulation or additional training. The E17 methylazoxymethanol acetate (MAM) exposure model bears many anatomical hallmarks seen in human MCDs as well as similar behavioral and cognitive deficits. We divided control and MAM exposed Sprague-Dawley rats into enriched and non-enriched groups and tested performance in the Morris water maze. Another group similarly divided underwent sociability testing and also underwent Magnetic Resonance Imaging (MRI) scans pre and post enrichment. A third group …


Socially Excluded Individuals Fail To Recruit Medial Prefrontal Cortex For Negative Social Scenes, Katherine E. Powers, Dylan D. Wagner, Catherine J. Norris, Todd F. Heatherton Nov 2013

Socially Excluded Individuals Fail To Recruit Medial Prefrontal Cortex For Negative Social Scenes, Katherine E. Powers, Dylan D. Wagner, Catherine J. Norris, Todd F. Heatherton

Dartmouth Scholarship

Converging behavioral evidence suggests that people respond to experiences of social exclusion with both defensive and affiliative strategies, allowing them to avoid further distress while also encouraging re-establishment of positive social connections. However, there are unresolved questions regarding the cognitive mechanisms underlying people's responses to social exclusion. Here, we sought to gain insight into these behavioral tendencies by using functional magnetic resonance imaging (fMRI) to examine the impact of social exclusion on neural responses to visual scenes that varied on dimensions of sociality and emotional valence. Compared to socially included participants, socially excluded participants failed to recruit dorsomedial prefrontal cortex …


The Dartmouth Database Of Children’S Faces: Acquisition And Validation Of A New Face Stimulus Set, Kirsten A. Dalrymple, Jesse Gomez, Brad Duchaine Nov 2013

The Dartmouth Database Of Children’S Faces: Acquisition And Validation Of A New Face Stimulus Set, Kirsten A. Dalrymple, Jesse Gomez, Brad Duchaine

Dartmouth Scholarship

Facial identity and expression play critical roles in our social lives. Faces are therefore frequently used as stimuli in a variety of areas of scientific research. Although several extensive and well-controlled databases of adult faces exist, few databases include children’s faces. Here we present the Dartmouth Database of Children’s Faces, a set of photographs of 40 male and 40 female Caucasian children between 6 and 16 years-of-age. Models posed eight facial expressions and were photographed from five camera angles under two lighting conditions. Models wore black hats and black gowns to minimize extra-facial variables. To validate the images, independent raters …


Mapping Disease At An Approximated Individual Level Using Aggregate Data: A Case Study Of Mapping New Hampshire Birth Defects, Xun Shi, Stephanie Miller, Kevin Mwenda, Akikazu Onda Sep 2013

Mapping Disease At An Approximated Individual Level Using Aggregate Data: A Case Study Of Mapping New Hampshire Birth Defects, Xun Shi, Stephanie Miller, Kevin Mwenda, Akikazu Onda

Dartmouth Scholarship

Limited by data availability, most disease maps in the literature are for relatively large and subjectively-defined areal units, which are subject to problems associated with polygon maps. High resolution maps based on objective spatial units are needed to more precisely detect associations between disease and environmental factors. Method: We propose to use a Restricted and Controlled Monte Carlo (RCMC) process to disaggregate polygon-level location data to achieve mapping aggregate data at an approximated individual level. RCMC assigns a random point location to a polygon-level location, in which the randomization is restricted by the polygon and controlled by the background (e.g., …


Self-Regulatory Depletion Increases Emotional Reactivity In The Amygdala, Dylan D. Wagner, Todd F. Heatherton Aug 2013

Self-Regulatory Depletion Increases Emotional Reactivity In The Amygdala, Dylan D. Wagner, Todd F. Heatherton

Dartmouth Scholarship

The ability to self-regulate can become impaired when people are required to engage in successive acts of effortful self-control, even when self-control occurs in different domains. Here, we used functional neuroimaging to test whether engaging in effortful inhibition in the cognitive domain would lead to putative dysfunction in the emotional domain. Forty-eight participants viewed images of emotional scenes during functional magnetic resonance imaging in two sessions that were separated by a challenging attention control task that required effortful inhibition (depletion group) or not (control group). Compared to the control group, depleted participants showed increased activity in the left amygdala to …


Geographic Variation In Chin Shape Challenges The Universal Facial Attractiveness Hypothesis, Zaneta M. Thayer, Seth D. Dobson Apr 2013

Geographic Variation In Chin Shape Challenges The Universal Facial Attractiveness Hypothesis, Zaneta M. Thayer, Seth D. Dobson

Dartmouth Scholarship

The universal facial attractiveness (UFA) hypothesis proposes that some facial features are universally preferred because they are reliable signals of mate quality. The primary evidence for this hypothesis comes from cross-cultural studies of perceived attractiveness. However, these studies do not directly address patterns of morphological variation at the population level. An unanswered question is therefore: Are universally preferred facial phenotypes geographically invariant, as the UFA hypothesis implies? The purpose of our study is to evaluate this often overlooked aspect of the UFA hypothesis by examining patterns of geographic variation in chin shape. We collected symphyseal outlines from 180 recent human …


Implicitly Priming The Social Brain: Failure To Find Neural Effects, Katherine E. Powers, Todd F. Heatherton Feb 2013

Implicitly Priming The Social Brain: Failure To Find Neural Effects, Katherine E. Powers, Todd F. Heatherton

Dartmouth Scholarship

Humans have a fundamental need for social relationships. Rejection from social groups is especially detrimental, rendering the ability to detect threats to social relationships and respond in adaptive ways critical. Indeed, previous research has shown that experiencing social rejection alters the processing of subsequent social cues in a variety of socially affiliative and avoidant ways. Because social perception and cognition occurs spontaneously and automatically, detecting threats to social relationships may occur without conscious awareness or control. Here, we investigated the automaticity of social threat detection by examining how implicit primes affect neural responses to social stimuli. However, despite using a …


Multivoxel Patterns In Face-Sensitive Temporal Regions Reveal An Encoding Schema Based On Detecting Life In A Face, Christine E. Looser, Jyothi S. Guntupalli, Thalia Wheatley Jul 2012

Multivoxel Patterns In Face-Sensitive Temporal Regions Reveal An Encoding Schema Based On Detecting Life In A Face, Christine E. Looser, Jyothi S. Guntupalli, Thalia Wheatley

Dartmouth Scholarship

More than a decade of research has demonstrated that faces evoke prioritized processing in a ‘core face network’ of three brain regions. However, whether these regions prioritize the detection of global facial form (shared by humans and mannequins) or the detection of life in a face has remained unclear. Here, we dissociate form-based and animacy-based encoding of faces by using animate and inanimate faces with human form (humans, mannequins) and dog form (real dogs, toy dogs). We used multivariate pattern analysis of BOLD responses to uncover the representational similarity space for each area in the core face network. Here, we …


Resilience In The Face Of Disaster: Prevalence And Longitudinal Course Of Mental Disorders Following Hurricane Ike, Robert H. Pietrzak, Melissa Tracy, Sandro Galea, Dean G. Kilpatrick, Kenneth J. Ruggiero, Jessica L. Hamblen, Steven M. Southwick, Fran H. Norris Jun 2012

Resilience In The Face Of Disaster: Prevalence And Longitudinal Course Of Mental Disorders Following Hurricane Ike, Robert H. Pietrzak, Melissa Tracy, Sandro Galea, Dean G. Kilpatrick, Kenneth J. Ruggiero, Jessica L. Hamblen, Steven M. Southwick, Fran H. Norris

Dartmouth Scholarship

Objectives: Natural disasters may increase risk for a broad range of psychiatric disorders, both in the short- and in the medium-term. We sought to determine the prevalence and longitudinal course of posttraumatic stress disorder (PTSD), generalized anxiety disorder (GAD), panic disorder (PD), depression, and suicidality in the first 18 months after Hurricane Ike.

Methods: Six hundred fifty-eight adults representative of Galveston and Chambers Counties, Texas participated in a random, population-based survey. The initial assessment was conducted 2 to 5 months after Hurricane Ike struck Galveston Bay on September 13, 2008. Follow-up assessments were conducted at 5 to 9 and 14 …


Unfakeable Facial Configurations Affect Strategic Choices In Trust Games With Or Without Information About Past Behavior, Constantin Rezlescu, Brad Duchaine, Christopher Y. Olivola, Nick Chater Mar 2012

Unfakeable Facial Configurations Affect Strategic Choices In Trust Games With Or Without Information About Past Behavior, Constantin Rezlescu, Brad Duchaine, Christopher Y. Olivola, Nick Chater

Dartmouth Scholarship

Background:

Many human interactions are built on trust, so widespread confidence in first impressions generally favors individuals with trustworthy-looking appearances. However, few studies have explicitly examined: 1) the contribution of unfakeable facial features to trust-based decisions, and 2) how these cues are integrated with information about past behavior.

Methodology/Principal Findings:

Using highly controlled stimuli and an improved experimental procedure, we show that unfakeable facial features associated with the appearance of trustworthiness attract higher investments in trust games. The facial trustworthiness premium is large for decisions based solely on faces, with trustworthy identities attracting 42% more money (Study 1), and remains …


Regional Gray Matter Correlates Of Perceived Emotional Intelligence, Nancy S. Koven, Robert M. Roth, Matthew A. Garlinghouse, Laura A. Flashman, Andrew J. Saykin Oct 2011

Regional Gray Matter Correlates Of Perceived Emotional Intelligence, Nancy S. Koven, Robert M. Roth, Matthew A. Garlinghouse, Laura A. Flashman, Andrew J. Saykin

Dartmouth Scholarship

Coping with stressful life events requires a degree of skill in the ability to attend to, comprehend, label, communicate and regulate emotions. Individuals vary in the extent to which these skills are developed, with the term ‘alexithymia’ often applied in the clinical and personality literature to those individuals most compromised in these skills. Although a frontal lobe model of alexithymia is emerging, it is unclear whether such a model satisfactorily reflects brain-related patterns associated with perceived emotional intelligence at the facet level. To determine whether these trait meta-mood facets (ability to attend to, have clarity of and repair emotions) have …


Assessing Medicare Beneficiaries’ Strength‐Of‐Preference Scores For Health Care Options: How Engaging Does The Elicitation Technique Need To Be?, Trafford Crump, Hilary A. Llewellyn-Thomas Jul 2011

Assessing Medicare Beneficiaries’ Strength‐Of‐Preference Scores For Health Care Options: How Engaging Does The Elicitation Technique Need To Be?, Trafford Crump, Hilary A. Llewellyn-Thomas

Dartmouth Scholarship

The objective was to determine if participants’ strength‐of‐preference scores for elective health care interventions at the end‐of‐life (EOL) elicited using a non‐engaging technique are affected by their prior use of an engaging elicitation technique.


Decision Quality Instrument For Treatment Of Hip And Knee Osteoarthritis: A Psychometric Evaluation, Karen R. Sepucha, Dawn Stacey, Catharine F. Clay, Yuchiao Chang Jul 2011

Decision Quality Instrument For Treatment Of Hip And Knee Osteoarthritis: A Psychometric Evaluation, Karen R. Sepucha, Dawn Stacey, Catharine F. Clay, Yuchiao Chang

Dartmouth Scholarship

A high quality decision requires that patients who meet clinical criteria for surgery are informed about the options (including non-surgical alternatives) and receive treatments that match their goals. The aim of this study was to evaluate the psychometric properties and clinical sensibility of a patient self report instrument, to measure the quality of decisions about total joint replacement for knee or hip osteoarthritis.


Aging Is Associated With Positive Responding To Neutral Information But Reduced Recovery From Negative Information, Carien M. Van Reekum, Stacey M. Schaefer, Regina C. Lapate, Catherine J. Norris, Lawrence L. Greischar, Richard J. Davidson Apr 2011

Aging Is Associated With Positive Responding To Neutral Information But Reduced Recovery From Negative Information, Carien M. Van Reekum, Stacey M. Schaefer, Regina C. Lapate, Catherine J. Norris, Lawrence L. Greischar, Richard J. Davidson

Dartmouth Scholarship

Studies on aging and emotion suggest an increase in reported positive affect, a processing bias of positive over negative information, as well as increasingly adaptive regulation in response to negative events with advancing age. These findings imply that older individuals evaluate information differently, resulting in lowered reactivity to, and/or faster recovery from, negative information, while maintaining more positive responding to positive information. We examined this hypothesis in an ongoing study on Midlife in the US (MIDUS II) where emotional reactivity and recovery were assessed in a large number of respondents (N = 159) from a wide age range (36–84 …


Differential Activation Of Frontoparietal Attention Networks By Social And Symbolic Spatial Cues, Andrew D. Engell, Lauri Nummenmaa, Nikolaas N. Oosterhof, Richard N. Henson, James V. Haxby, Andrew J. Calder Mar 2010

Differential Activation Of Frontoparietal Attention Networks By Social And Symbolic Spatial Cues, Andrew D. Engell, Lauri Nummenmaa, Nikolaas N. Oosterhof, Richard N. Henson, James V. Haxby, Andrew J. Calder

Dartmouth Scholarship

Perception of both gaze-direction and symbolic directional cues (e.g. arrows) orient an observer’s attention toward the indicated location. It is unclear, however, whether these similar behavioral effects are examples of the same attentional phenomenon and, therefore, subserved by the same neural substrate. It has been proposed that gaze, given its evolutionary significance, constitutes a ‘special’ category of spatial cue. As such, it is predicted that the neural systems supporting spatial reorienting will be different for gaze than for non-biological symbols. We tested this prediction using functional magnetic resonance imaging to measure the brain’s response during target localization in which laterally …


Bold Signal In Both Ipsilateral And Contralateral Retinotopic Cortex Modulates With Perceptual Fading, Po-Jang Hsieh, Peter U. Tse Mar 2010

Bold Signal In Both Ipsilateral And Contralateral Retinotopic Cortex Modulates With Perceptual Fading, Po-Jang Hsieh, Peter U. Tse

Dartmouth Scholarship

Under conditions of visual fixation, perceptual fading occurs when a stationary object, though present in the world and continually casting light upon the retina, vanishes from visual consciousness. The neural correlates of the consciousness of such an object will presumably modulate in activity with the onset and cessation of perceptual fading.

Method: In order to localize the neural correlates of perceptual fading, a green disk that had been individually set to be equiluminant with the orange background, was presented in one of the four visual quadrants; Subjects indicated with a button press whether or not the disk was subjectively visible …


Behind The Mask: The Influence Of Mask-Type On Amygdala Response To Fearful Faces, M Justin Kim, Rebecca A. Loucks, Maital Neta, F. Caroline Davis, Jonathan A. Oler, Emily C. Mazzulla, Paul J. Whalen Feb 2010

Behind The Mask: The Influence Of Mask-Type On Amygdala Response To Fearful Faces, M Justin Kim, Rebecca A. Loucks, Maital Neta, F. Caroline Davis, Jonathan A. Oler, Emily C. Mazzulla, Paul J. Whalen

Dartmouth Scholarship

In this study, we compared the effects of using neutral face masks vs non-face pattern masks on amygdala activity to masked fearful faces. Twenty-seven subjects viewed 18 s blocks of either fearful or happy faces masked with either neutral faces or patterns, while their brain activity was measured using functional magnetic resonance imaging. Results replicated increased amygdala activation to face-masked fearful vs happy faces. In the pattern mask condition, the amygdala discriminated between masked fearful and happy faces, but this effect manifested as a decrease in activation to fearful faces compared to happy faces. This interactive effect between facial expression …


Microsaccade Rate Varies With Subjective Visibility During Motion-Induced Blindness, Po-Jang Hsieh, Peter U. Tse Apr 2009

Microsaccade Rate Varies With Subjective Visibility During Motion-Induced Blindness, Po-Jang Hsieh, Peter U. Tse

Dartmouth Scholarship

Motion-induced blindness (MIB) occurs when a dot embedded in a motion field subjectively vanishes. Here we report the first psychophysical data concerning effects of microsaccade/eyeblink rate upon perceptual switches during MIB. We find that the rate of microsaccades/eyeblink rises before and after perceptual transitions from not seeing to seeing the dot, and decreases before perceptual transitions from seeing it to not seeing it. In addition, event-related fMRI data reveal that, when a dot subjectively reappears during MIB, the blood oxygen-level dependent (BOLD) signal increases in V1v and V2v and decreases in contralateral hMT+. These BOLD signal changes observed upon perceptual …


Small Individual Loans And Mental Health: A Randomized Controlled Trial Among South African Adults, Lia C. H. Fernald, Rita Hamad, Dean Karlan, Emily J. Ozer, Jonathan Zinman Dec 2008

Small Individual Loans And Mental Health: A Randomized Controlled Trial Among South African Adults, Lia C. H. Fernald, Rita Hamad, Dean Karlan, Emily J. Ozer, Jonathan Zinman

Dartmouth Scholarship

Background: In the developing world, access to small, individual loans has been variously hailed as a poverty-alleviation tool – in the context of "microcredit" – but has also been criticized as "usury" and harmful to vulnerable borrowers. Prior studies have assessed effects of access to credit on traditional economic outcomes for poor borrowers, but effects on mental health have been largely ignored.

Methods: Applicants who had previously been rejected (n = 257) for a loan (200% annual percentage rate – APR) from a lender in South Africa were randomly assigned to a "second-look" that encouraged loan officers to approve their …