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Full-Text Articles in Neuroscience and Neurobiology
Multimodal Frontostriatal Connectivity Underlies Individual Differences In Self-Esteem, Robert S. Chavez, Todd F. Heatherton
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 …
Belief About Nicotine Selectively Modulates Value And Reward Prediction Error Signals In Smokers, Xiaosi Gu, Terry Lohrenz, Ramiro Salas, Philip R. Baldwin, Alireza Soltani
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 …
Dissociation Between Face Perception And Face Memory In Adults, But Not Children, With Developmental Prosopagnosia, Kirsten A. Dalrymple, Lúcia Garrido, Brad Duchaine
Dissociation Between Face Perception And Face Memory In Adults, But Not Children, With Developmental Prosopagnosia, Kirsten A. Dalrymple, Lúcia Garrido, Brad Duchaine
Dartmouth Scholarship
Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP). To address this issue, we tested the face perception and face memory of children and adults with DP. By …
The N400 As An Index Of Racial Stereotype Accessibility, Eric Hehman, Hannah I. Volpert, Robert F. Simons
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 …
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
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
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 …
Self-Regulatory Depletion Increases Emotional Reactivity In The Amygdala, Dylan D. Wagner, Todd F. Heatherton
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 …
Implicitly Priming The Social Brain: Failure To Find Neural Effects, Katherine E. Powers, Todd F. Heatherton
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 …
Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García
Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García
Dartmouth Scholarship
ADA is an enzyme implicated in purine metabolism, and is critical to ensure normal immune function. Its congenital deficit leads to severe combined immunodeficiency (SCID). ADA binding to adenosine receptors on dendritic cell surface enables T-cell costimulation through CD26 crosslinking, which enhances T-cell activation and proliferation. Despite a large body of work on the actions of the ecto-enzyme ADA on T-cell activation, questions arise on whether ADA can also modulate dendritic cell maturation. To this end we investigated the effects of ADA on human monocyte derived dendritic cell biology. Our results show that both the enzymatic and non-enzymatic activities of …
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
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 …
Amygdala Responses To Averted Vs Direct Gaze Fear Vary As A Function Of Presentation Speed, Reginald B. Adams, Robert G. Franklin Jr, Kestutis Kveraga, Nalini Ambady, Robert E. Kleck, Paul J. Whalen, Nouchine Hadjikhani, Anthony J. Nelson
Amygdala Responses To Averted Vs Direct Gaze Fear Vary As A Function Of Presentation Speed, Reginald B. Adams, Robert G. Franklin Jr, Kestutis Kveraga, Nalini Ambady, Robert E. Kleck, Paul J. Whalen, Nouchine Hadjikhani, Anthony J. Nelson
Dartmouth Scholarship
We examined whether amygdala responses to rapidly presented fear expressions are preferentially tuned to averted vs direct gaze fear and conversely whether responses to more sustained presentations are preferentially tuned to direct vs averted gaze fear. We conducted three functional magnetic resonance imaging (fMRI) studies to test these predictions including: Study 1: a block design employing sustained presentations (1 s) of averted vs direct gaze fear expressions taken from the Pictures of Facial Affect; Study 2: a block design employing rapid presentations (300 ms) of these same stimuli and Study 3: a direct replication of these studies in the context …
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
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 …
Mind Perception: Real But Not Artificial Faces Sustain Neural Activity Beyond The N170/Vpp, Thalia Wheatley, Anna Weinberg, Christine Looser, Tim Moran, Greg Hajcak
Mind Perception: Real But Not Artificial Faces Sustain Neural Activity Beyond The N170/Vpp, Thalia Wheatley, Anna Weinberg, Christine Looser, Tim Moran, Greg Hajcak
Dartmouth Scholarship
Faces are visual objects that hold special significance as the icons of other minds. Previous researchers using event-related potentials (ERPs) have found that faces are uniquely associated with an increased N170/vertex positive potential (VPP) and a more sustained frontal positivity. Here, we examined the processing of faces as objects vs. faces as cues to minds by contrasting images of faces possessing minds (human faces), faces lacking minds (doll faces), and non-face objects (i.e., clocks). Although both doll and human faces were associated with an increased N170/VPP from 175–200 ms following stimulus onset, only human faces were associated with a sustained …
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
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 …
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
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
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 …
Medial Temporal Lobe Bold Activity At Rest Predicts Individual Differences In Memory Ability In Hhealthy Young Adults, Gagan S. Wig, Scott T. Grafton, Kathryn E. Demos, George L. Wolford, Steven E. Petersen, William M. Kelley
Medial Temporal Lobe Bold Activity At Rest Predicts Individual Differences In Memory Ability In Hhealthy Young Adults, Gagan S. Wig, Scott T. Grafton, Kathryn E. Demos, George L. Wolford, Steven E. Petersen, William M. Kelley
Dartmouth Scholarship
Human beings differ in their ability to form and retrieve lasting long-term memories. To explore the source of these individual differences, we used functional magnetic resonance imaging to measure blood-oxygen-level-dependent (BOLD) activity in healthy young adults (n = 50) during periods of resting fixation that were interleaved with periods of simple cognitive tasks. We report that medial temporal lobe BOLD activity during periods of rest predicts individual differences in memory ability. Specifically, individuals who exhibited greater magnitudes of task-induced deactivations in medial temporal lobe BOLD signal (as compared to periods of rest) demonstrated superior memory during offline testing. This relationship …
Switching Language Switches Mind: Linguistic Effects On Developmental Neural Bases Of ‘Theory Of Mind’, Chiyoko Kobayashi, Gary H. Glover, Elise Temple
Switching Language Switches Mind: Linguistic Effects On Developmental Neural Bases Of ‘Theory Of Mind’, Chiyoko Kobayashi, Gary H. Glover, Elise Temple
Dartmouth Scholarship
Theory of mind (ToM)—our ability to predict behaviors of others in terms of their underlying intentions—has been examined through false-belief (FB) tasks. We studied 12 Japanese early bilingual children (8−12 years of age) and 16 late bilingual adults (18−40 years of age) with FB tasks in Japanese [first language (L1)] and English [second language (L2)], using fMRI. Children recruited more brain regions than adults for processing ToM tasks in both languages. Moreover, children showed an overlap in brain activity between the L1 and L2 ToM conditions in the medial prefrontal cortex (mPFC). Adults did not show such a convergent activity …
Detecting Agency From The Biological Motion Of Veridical Vs Animated Agents, Raymond A. Mar, William M. Kelley, Todd F. Heatherton, C. Neil Macrae
Detecting Agency From The Biological Motion Of Veridical Vs Animated Agents, Raymond A. Mar, William M. Kelley, Todd F. Heatherton, C. Neil Macrae
Dartmouth Scholarship
The ability to detect agency is fundamental for understanding the social world. Underlying this capacity are neural circuits that respond to patterns of intentional biological motion in the superior temporal sulcus and temporoparietal junction. Here we show that the brain's blood oxygenation level dependent (BOLD) response to such motion is modulated by the representation of the actor. Dynamic social interactions were portrayed by either live-action agents or computer-animated agents, enacting the exact same patterns of biological motion. Using an event-related design, we found that the BOLD response associated with the perception and interpretation of agency was greater when identical physical …
Prior Experience As A Stimulus Category Confound: An Example Using Facial Expressions Of Emotion, Leah H. Somerville, Paul J. Whalen
Prior Experience As A Stimulus Category Confound: An Example Using Facial Expressions Of Emotion, Leah H. Somerville, Paul J. Whalen
Dartmouth Scholarship
Facial expressions of emotion represent a stimulus set widely used to assess a broad range of psychological processes. However, a consideration of systematic differences between expression categories, other than differences relating to characteristics of the expressions themselves, has remained largely unaddressed. By collecting experience rankings in a large sample of undergraduates, we observed that the amount of reported experience individuals have had with different facial expressions of emotion systematically differed between all expression categories. These findings shed light on the potential for identifying confounds inherent to comparing some stimulus categories and, in this case, may aid in the interpretation of …
Medial Prefrontal Activity Differentiates Self From Close Others, Todd F. Heatherton, Carrie L. Wyland, C. Neil Macrae, Kathryn E. Demos, Bryan T. Denny, William M. Kelley
Medial Prefrontal Activity Differentiates Self From Close Others, Todd F. Heatherton, Carrie L. Wyland, C. Neil Macrae, Kathryn E. Demos, Bryan T. Denny, William M. Kelley
Dartmouth Scholarship
No abstract provided.
Visibility, Visual Awareness, And Visual Masking Of Simple Unattended Targets Are Confined To Areas In The Occipital Cortex Beyond Human V1/V2, Peter U. Tse, Susanna Martinez-Conde, Alexander A. Schlegel, Stephen L. Macknik
Visibility, Visual Awareness, And Visual Masking Of Simple Unattended Targets Are Confined To Areas In The Occipital Cortex Beyond Human V1/V2, Peter U. Tse, Susanna Martinez-Conde, Alexander A. Schlegel, Stephen L. Macknik
Dartmouth Scholarship
In visual masking, visible targets are rendered invisible by modifying the context in which they are presented, but not by modifying the targets themselves. Here, we localize the neuronal correlates of visual awareness in the human brain by using visual masking illusions. We compare monoptic visual masking activation, which we find within all retinotopic visual areas, with dichoptic masking activation, which we find only in those retinotopic areas downstream of V2. Because monoptic and dichoptic masking are equivalent in magnitude perceptually, the present results establish a lower bound for maintenance of visual awareness of simple unattended targets. Moreover, we find …
Donepezil Effects On Mood In Patients With Schizophrenia And Schizoaffective Disorder, S Craig Risch, Michael D. Horner, Susan R. Mcgurk, Simmy Palecko, John S. Markowitz, Ziad Nahas, C. Lindsay Devane
Donepezil Effects On Mood In Patients With Schizophrenia And Schizoaffective Disorder, S Craig Risch, Michael D. Horner, Susan R. Mcgurk, Simmy Palecko, John S. Markowitz, Ziad Nahas, C. Lindsay Devane
Dartmouth Scholarship
Donepezil, 5 mg/d for 6 wk then 10 mg/d for 6 wk, and placebo daily for 12 wk in a double-blind cross-over paradigm, was added to the therapeutic regimen of 13 patients with schizophrenia or schizoaffective disorders, clinically stable on atypical antipsychotic medications. Patients had varying degrees of depressive symptoms, ranging from no depression to clinically significant depression. There was no worsening or induction of depression in individual patients or the group as a whole. In addition there was a statistically significant antidepressant effect in the group as a whole during the donepezil condition and a clinically significant antidepressant effect …
Il-23 Produced By Cns-Resident Cells Controls T Cell Encephalitogenicity During The Effector Phase Of Experimental Autoimmune Encephalomyelitis, Burkhard Becher, Brigit G. Durell, Randolph J. Noelle
Il-23 Produced By Cns-Resident Cells Controls T Cell Encephalitogenicity During The Effector Phase Of Experimental Autoimmune Encephalomyelitis, Burkhard Becher, Brigit G. Durell, Randolph J. Noelle
Dartmouth Scholarship
CNS-resident cells, in particular microglia and macrophages, are a source of inflammatory cytokines during inflammation within the CNS. Expression of IL-23, a recently discovered cytokine, has been shown to be critical for the development of experimental autoimmune encephalomyelitis (EAE) in mice. Expression of the p40 subunit of IL-12 and IL-23 by microglia has been shown in situ and in vitro, but direct evidence for a functional significance of p40 expression by CNS cells during an immune response in vivo is still lacking. Here we report that p40 plays a critical role in maintaining encephalitogenicity during the disease course. By using …
Distinct Neural Systems Subserve Person And Object Knowledge, Jason P. Mitchell, Todd F. Heatherton, C. Neil Macrae
Distinct Neural Systems Subserve Person And Object Knowledge, Jason P. Mitchell, Todd F. Heatherton, C. Neil Macrae
Dartmouth Scholarship
Studies using functional neuroimaging and patient populations have demonstrated that distinct brain regions subserve semantic knowledge for different classes of inanimate objects (e.g., tools, musical instruments, and houses). What this work has yet to consider, however, is how conceptual knowledge about people may be organized in the brain. In particular, is there a distinct functional neuroanatomy associated with person knowledge? By using event-related functional magnetic resonance imaging (fMRI), we measured neural activity while participants made semantic judgments about people or objects. A unique pattern of brain activity was associated with person judgments and included brain regions previously implicated in other …