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Daniel Tranel - One of the best experts on this subject based on the ideXlab platform.
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Ventromedial Prefrontal Cortex Is Critical for Helping Others Who Are Suffering.
Frontiers in Neurology, 2018Co-Authors: Janelle N. Beadle, Sergio Paradiso, Daniel TranelAbstract:Neurological patients with damage to the Ventromedial Prefrontal Cortex are reported to display reduced empathy towards others in their daily lives in clinical case studies. However, the empathic behavior of patients with damage to the Ventromedial Prefrontal Cortex has not been measured experimentally in response to an empathy-eliciting event. This is important because characterizing the degree to which patients with damage to the Ventromedial Prefrontal Cortex have lower empathic behavior will allow for the development of targeted interventions to improve patients’ social skills and in turn will help family members to better understand their impairments so they can provide appropriate supports. For the first time, we induced empathy using an ecologically-valid empathy induction in neurological patients with damage to the Ventromedial Prefrontal Cortex and measured their empathic emotional responses and behavior in real time. Eight neurological patients with focal damage to the Ventromedial Prefrontal Cortex were compared to demographically-matched brain-damaged and healthy comparison participants. Patients with damage to the Ventromedial Prefrontal Cortex gave less money in the empathy condition to a person who was suffering (a confederate) than comparison participants. This provides the first direct experimental evidence that the Ventromedial Prefrontal Cortex is critical for empathic behavior towards individuals who are suffering.
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Ventromedial Prefrontal Cortex Is Critical for Helping Others Who Are Suffering
Frontiers in neurology, 2018Co-Authors: Janelle N. Beadle, Sergio Paradiso, Daniel TranelAbstract:Neurological patients with damage to the Ventromedial Prefrontal Cortex (vmPFC) are reported to display reduced empathy toward others in their daily lives in clinical case studies. However, the empathic behavior of patients with damage to the vmPFC has not been measured experimentally in response to an empathy-eliciting event. This is important because characterizing the degree to which patients with damage to the vmPFC have lower empathic behavior will allow for the development of targeted interventions to improve patients' social skills and in turn will help family members to better understand their impairments so they can provide appropriate supports. For the first time, we induced empathy using an ecologically-valid empathy induction in neurological patients with damage to the vmPFC and measured their empathic emotional responses and behavior in real time. Eight neurological patients with focal damage to the vmPFC were compared to demographically-matched brain-damaged and healthy comparison participants. Patients with damage to the vmPFC gave less money in the empathy condition to a person who was suffering (a confederate) than comparison participants. This provides the first direct experimental evidence that the vmPFC is critical for empathic behavior toward individuals who are suffering.
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Ventromedial Prefrontal Cortex Is Necessary for Normal Associative Inference and Memory Integration.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2018Co-Authors: Kelsey N. Spalding, Daniel Tranel, Melissa C. Duff, Alison R. Preston, Dagmar Zeithamova, Margaret L. Schlichting, David E. WarrenAbstract:The ability to flexibly combine existing knowledge in response to novel circumstances is highly adaptive. However, the neural correlates of flexible associative inference are not well-characterized. Laboratory tests of associative inference have measured memory for overlapping pairs of studied items (e.g., AB, BC) and for non-studied pairs with common associates (i.e., AC). Findings from functional neuroimaging and neuropsychology suggest the Ventromedial Prefrontal Cortex (vmPFC) may be necessary for associative inference. Here, we used a neuropsychological approach to test the necessity of vmPFC for successful memory-guided associative inference in humans using an overlapping pairs associative memory task. We predicted that individuals with focal vmPFC damage (N=5; 3F, 2M) would show impaired inferential memory but intact non-inferential memory. Performance was compared to normal comparison participants (N=10; 6F, 4M). Participants studied pairs of visually-presented objects including overlapping pairs (AB, BC) and non-overlapping pairs (XY). Participants later completed a three-alternative forced-choice recognition task for studied pairs (AB, BC, XY) and inference pairs (AC). As predicted, the vmPFC group had intact memory for studied pairs but significantly impaired memory for inferential pairs. These results are consistent with the perspective that the vmPFC is necessary for memory-guided associative inference, indicating that the vmPFC is critical for adaptive abilities that require application of existing knowledge to novel circumstances. Additionally, vmPFC damage was associated with unexpectedly reduced memory for AB pairs post-inference, which could potentially reflect retroactive interference. Together, these results reinforce an emerging understanding of a role for the vmPFC in brain networks supporting associative memory processes. SIGNIFICANCE STATEMENT We live in a constantly changing environment, so the ability to adapt our knowledge to support understanding of new circumstances is essential. One important adaptive ability is associative inference — it allows us to extract shared features from distinct experiences and relate them. For example, if we see a woman holding a baby, and later see a man holding the same baby, then we might infer that the two adults are a couple. Despite the importance of associative inference, the brain systems necessary for this ability are not known. Here, we report that damage to human Ventromedial Prefrontal Cortex (vmPFC) disproportionately impairs associative inference. Our findings show the necessity of the vmPFC for normal associative inference and memory integration.
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selective impairment of goal directed decision making following lesions to the human Ventromedial Prefrontal Cortex
Brain, 2017Co-Authors: Justin Reber, Ralph Adolphs, Justin S Feinstein, John P Odoherty, Mimi Liljeholm, Daniel TranelAbstract:Neuroimaging studies suggest that the human Ventromedial Prefrontal Cortex is a key region for goal-directed behaviour. However, it remains unclear whether the Ventromedial Prefrontal Cortex is necessary for such behaviour. Here we used a canonical test from the animal literature designed to distinguish goal-directed from habit-based choice: namely, outcome devaluation. Patients with focal damage to the Ventromedial Prefrontal Cortex showed deficits in goal-directed choice by persistently selecting actions for a food outcome that had been devalued through selective satiation. By contrast, the same patients had entirely intact acquisition of instrumental contingencies, demonstrating preserved habitual control, and also gave normal ratings of the hedonic value of the devalued food. These findings for the first time demonstrate a necessary and selective role for the human Ventromedial Prefrontal Cortex in goal-directed choice, reconciling prior neuroimaging results in humans with lesion studies in animals, and providing a mechanistic explanation of the real-life deficits in decision-making that have been documented in patients with damage to this structure.
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Damage to the Ventromedial Prefrontal Cortex Impairs Learning from Observed Outcomes
Cerebral cortex (New York N.Y. : 1991), 2015Co-Authors: Dharshan Kumaran, David E. Warren, Daniel TranelAbstract:Individuals learn both from the outcomes of their own internally generated actions (“experiential learning”) and from the observation of the consequences of externally generated actions (“observational learning”). While neuroscience research has focused principally on the neural mechanisms by which brain structures such as the Ventromedial Prefrontal Cortex (vmPFC) support experiential learning, relatively less is known regarding how learning proceeds through passive observation. We explored the necessity of the vmPFC for observational learning by testing a group of patients with damage to the vmPFC as well as demographically matched normal comparison and brain-damaged comparison groups—and a single patient with bilateral dorsal Prefrontal damage—using several value-learning tasks that required learning from direct experience, observational learning, or both. We found a specific impairment in observational learning in patients with vmPFC damage manifest in the reduced influence of previously observed rewards on current choices, despite a relatively intact capacity for experiential learning. The current study provides evidence that the vmPFC plays a critical role in observational learning, suggests that there are dissociable neural circuits for experiential and observational learning, and offers an important new extension of how the vmPFC contributes to learning and memory.
Michael Koenigs - One of the best experts on this subject based on the ideXlab platform.
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Human lesion studies of Ventromedial Prefrontal Cortex.
Neuropsychologia, 2017Co-Authors: Brett Schneider, Michael KoenigsAbstract:Studies of neurological patients with focal lesions involving Ventromedial Prefrontal Cortex (vmPFC) have demonstrated a critical role for this brain area in various aspects of cognition, emotion, and behavior. In this article, we review the key themes, methods, and findings from neuropsychological research on vmPFC lesion patients. Early case studies demonstrated profound disruptions in personality and behavior following vmPFC damage, including blunted affect, poor decision-making, and inappropriate social behavior. Subsequent laboratory investigations with groups of vmPFC lesion patients have revealed deficits in a host of interrelated functions, such as value-based decision-making, future and counterfactual thinking, physiological arousal to emotional stimuli, emotion recognition, empathy, moral judgment, and memory confabulation. The compendium of findings described here demonstrates that vmPFC is crucial for diverse aspects of adaptive function.
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Ventromedial Prefrontal Cortex Damage Is Associated with Decreased Ventral Striatum Volume and Response to Reward
The Journal of Neuroscience, 2016Co-Authors: Maia Pujara, Carissa L. Philippi, Julian C. Motzkin, Mustafa K Baskaya, Michael KoenigsAbstract:The ventral striatum and Ventromedial Prefrontal Cortex (vmPFC) are two central nodes of the “reward circuit” of the brain. Human neuroimaging studies have demonstrated coincident activation and functional connectivity between these brain regions, and animal studies have demonstrated that the vmPFC modulates ventral striatum activity. However, there have been no comparable data in humans to address whether the vmPFC may be critical for the reward-related response properties of the ventral striatum. In this study, we used fMRI in five neurosurgical patients with focal vmPFC lesions to test the hypothesis that the vmPFC is necessary for enhancing ventral striatum responses to the anticipation of reward. In support of this hypothesis, we found that, compared with age- and gender-matched neurologically healthy subjects, the vmPFC-lesioned patients had reduced ventral striatal activity during the anticipation of reward. Furthermore, we observed that the vmPFC-lesioned patients had decreased volumes of the accumbens subregion of the ventral striatum. Together, these functional and structural neuroimaging data provide novel evidence for a critical role for the vmPFC in contributing to reward-related activity of the ventral striatum. These results offer new insight into the functional and structural interactions between key components of the brain circuitry underlying human affective function and decision-making. SIGNIFICANCE STATEMENT Maladaptive decision-making is a common problem across multiple mental health disorders. Developing new pathophysiologically based strategies for diagnosis and treatment thus requires a better understanding of the brain circuits responsible for adaptive decision-making and related psychological subprocesses (e.g., reward valuation, anticipation, and motivation). Animal studies provide evidence that these functions are mediated through direct interactions between two key nodes of a posited “reward circuit,” the ventral striatum and the Ventromedial Prefrontal Cortex (vmPFC). For the first time in humans, we demonstrate that damage to the vmPFC results in decreased ventral striatum activity during reward anticipation. These data provide unique evidence on the causal mechanisms by which the vmPFC and ventral striatum interact during the anticipation of rewards.
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Ventromedial Prefrontal Cortex Lesions Alter Neural and Physiological Correlates of Anticipation
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2014Co-Authors: Julian C. Motzkin, Carissa L. Philippi, Mustafa K Baskaya, Richard C. Wolf, Michael KoenigsAbstract:Uncertainty is a ubiquitous feature of our daily lives. Although previous studies have identified a number of neural and peripheral physiological changes associated with uncertainty, there are limited data on the causal mechanisms underlying these responses in humans. In this study, we address this empirical gap through a novel application of fMRI in neurosurgical patients with focal, bilateral Ventromedial Prefrontal Cortex (vmPFC) damage. The fMRI task involved cued anticipation of aversive and neutral picture stimuli; “certain” cues unambiguously indicated the upcoming picture valence, whereas “ambiguous” cues could precede either picture type. Healthy subjects exhibited robust bilateral insula responses to ambiguous cues, and this cue-related insula activity significantly correlated with heart rate variability during the task. By contrast, the vmPFC lesion patients exhibited altered cue-related insula activity and reduced heart rate variability. These findings suggest a role for vmPFC in coordinating neural and physiological responses during anticipation.
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Ventromedial Prefrontal Cortex mediates visual attention during facial emotion recognition.
Brain, 2014Co-Authors: Richard C. Wolf, Carissa L. Philippi, Julian C. Motzkin, Mustafa K Baskaya, Michael KoenigsAbstract:The Ventromedial Prefrontal Cortex is known to play a crucial role in regulating human social and emotional behaviour, yet the precise mechanisms by which it subserves this broad function remain unclear. Whereas previous neuropsychological studies have largely focused on the role of the Ventromedial Prefrontal Cortex in higher-order deliberative processes related to valuation and decision-making, here we test whether Ventromedial Prefrontal Cortex may also be critical for more basic aspects of orienting attention to socially and emotionally meaningful stimuli. Using eye tracking during a test of facial emotion recognition in a sample of lesion patients, we show that bilateral Ventromedial Prefrontal Cortex damage impairs visual attention to the eye regions of faces, particularly for fearful faces. This finding demonstrates a heretofore unrecognized function of the Ventromedial Prefrontal Cortex—the basic attentional process of controlling eye movements to faces expressing emotion.
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functional anatomy of Ventromedial Prefrontal Cortex implications for mood and anxiety disorders
Molecular Psychiatry, 2012Co-Authors: Blake Myersschulz, Michael KoenigsAbstract:In recent years, an increasing number of neuroimaging studies have sought to identify the brain anomalies associated with mood and anxiety disorders. The results of such studies could have significant implications for the development of novel treatments for these disorders. A challenge currently facing the field is to assimilate the large and growing corpus of imaging data to inform a systems-level model of the neural circuitry underlying the disorders. One prominent theoretical perspective highlights the top–down inhibition of amygdala by Ventromedial Prefrontal Cortex (vmPFC) as a crucial neural mechanism that may be defective in certain mood and anxiety disorders, such as major depression and posttraumatic stress disorder. In this article, we provide a critical review of animal and human data related to this model. In particular, we emphasize the considerable body of research that challenges the veracity (or at least completeness) of the predominant model. We propose a framework for constructing a more comprehensive model of vmPFC function, with the goal of fostering further progress in understanding the neuropathophysiological basis of mood and anxiety disorders. Molecular Psychiatry (2012) 17, 132–141; doi:10.1038/mp.2011.88; published online 26 July 2011
Antonio Rangel - One of the best experts on this subject based on the ideXlab platform.
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emotional and utilitarian appraisals of moral dilemmas are encoded in separate areas and integrated in Ventromedial Prefrontal Cortex
The Journal of Neuroscience, 2015Co-Authors: Cendri A. Hutcherson, James Woodward, Leila Montaserkouhsari, Antonio RangelAbstract:Moral judgment often requires making difficult tradeoffs (e.g., is it appropriate to torture to save the lives of innocents at risk?). Previous research suggests that both emotional appraisals and more deliberative utilitarian appraisals influence such judgments and that these appraisals often conflict. However, it is unclear how these different types of appraisals are represented in the brain, or how they are integrated into an overall moral judgment. We addressed these questions using an fMRI paradigm in which human subjects provide separate emotional and utilitarian appraisals for different potential actions, and then make difficult moral judgments constructed from combinations of these actions. We found that anterior cingulate, insula, and superior temporal gyrus correlated with emotional appraisals, whereas temporoparietal junction and dorsomedial Prefrontal Cortex correlated with utilitarian appraisals. Overall moral value judgments were represented in an anterior portion of the Ventromedial Prefrontal Cortex. Critically, the pattern of responses and functional interactions between these three sets of regions are consistent with a model in which emotional and utilitarian appraisals are computed independently and in parallel, and passed to the Ventromedial Prefrontal Cortex where they are integrated into an overall moral value judgment.
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Emotional and Utilitarian Appraisals of Moral Dilemmas Are Encoded in Separate Areas and Integrated in Ventromedial Prefrontal Cortex.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2015Co-Authors: Cendri A. Hutcherson, Leila Montaser-kouhsari, James Woodward, Antonio RangelAbstract:Moral judgment often requires making difficult tradeoffs (e.g., is it appropriate to torture to save the lives of innocents at risk?). Previous research suggests that both emotional appraisals and more deliberative utilitarian appraisals influence such judgments and that these appraisals often conflict. However, it is unclear how these different types of appraisals are represented in the brain, or how they are integrated into an overall moral judgment. We addressed these questions using an fMRI paradigm in which human subjects provide separate emotional and utilitarian appraisals for different potential actions, and then make difficult moral judgments constructed from combinations of these actions. We found that anterior cingulate, insula, and superior temporal gyrus correlated with emotional appraisals, whereas temporoparietal junction and dorsomedial Prefrontal Cortex correlated with utilitarian appraisals. Overall moral value judgments were represented in an anterior portion of the Ventromedial Prefrontal Cortex. Critically, the pattern of responses and functional interactions between these three sets of regions are consistent with a model in which emotional and utilitarian appraisals are computed independently and in parallel, and passed to the Ventromedial Prefrontal Cortex where they are integrated into an overall moral value judgment. Significance statement: Popular accounts of moral judgment often describe it as a battle for control between two systems, one intuitive and emotional, the other rational and utilitarian, engaged in winner-take-all inhibitory competition. Using a novel fMRI paradigm, we identified distinct neural signatures of emotional and utilitarian appraisals and used them to test different models of how they compete for the control of moral behavior. Importantly, we find little support for competitive inhibition accounts. Instead, moral judgments resembled the architecture of simple economic choices: distinct regions represented emotional and utilitarian appraisals independently and passed this information to the Ventromedial Prefrontal Cortex for integration into an overall moral value signal.
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Category-dependent and category-independent goal-value codes in human Ventromedial Prefrontal Cortex
Nature neuroscience, 2013Co-Authors: Daniel Mcnamee, Antonio Rangel, John P. O'dohertyAbstract:To choose between manifestly distinct options, it is suggested that the brain assigns values to goals using a common currency. Although previous studies have reported activity in Ventromedial Prefrontal Cortex (vmPFC) correlating with the value of different goal stimuli, it remains unclear whether such goal-value representations are independent of the associated stimulus categorization, as required by a common currency. Using multivoxel pattern analyses on functional magnetic resonance imaging (fMRI) data, we found a region of medial Prefrontal Cortex to contain a distributed goal-value code that is independent of stimulus category. More ventrally in the vmPFC, we found spatially distinct areas of the medial orbitofrontal Cortex to contain unique category-dependent distributed value codes for food and consumer items. These results implicate the medial Prefrontal Cortex in the implementation of a common currency and suggest a ventral versus dorsal topographical organization of value signals in the vmPFC.
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Dynamic construction of stimulus values in the Ventromedial Prefrontal Cortex
PLoS ONE, 2011Co-Authors: Alison Harris, Colin Camerer, Ralph Adolphs, Antonio RangelAbstract:Signals representing the value assigned to stimuli at the time of choice have been repeatedly observed in Ventromedial Prefrontal Cortex (vmPFC). Yet it remains unknown how these value representations are computed from sensory and memory representations in more posterior brain regions. We used electroencephalography (EEG) while subjects evaluated appetitive and aversive food items to study how event-related responses modulated by stimulus value evolve over time. We found that value-related activity shifted from posterior to anterior, and from parietal to central to frontal sensors, across three major time windows after stimulus onset: 150-250 ms, 400-550 ms, and 700-800 ms. Exploratory localization of the EEG signal revealed a shifting network of activity moving from sensory and memory structures to areas associated with value coding, with stimulus value activity localized to vmPFC only from 400 ms onwards. Consistent with these results, functional connectivity analyses also showed a causal flow of information from temporal Cortex to vmPFC. Thus, although value signals are present as early as 150 ms after stimulus onset, the value signals in vmPFC appear relatively late in the choice process, and seem to reflect the integration of incoming information from sensory and memory related regions.
Elisa Ciaramelli - One of the best experts on this subject based on the ideXlab platform.
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Boundary extension is attenuated in patients with Ventromedial Prefrontal Cortex damage.
Cortex; a journal devoted to the study of the nervous system and behavior, 2018Co-Authors: Flavia De Luca, Eleanor A. Maguire, Cornelia Mccormick, Sinéad L. Mullally, Helene Intraub, Elisa CiaramelliAbstract:Abstract The Ventromedial Prefrontal Cortex (vmPFC) and hippocampus have been implicated in the mental construction of scenes and events. However, little is known about their specific contributions to these cognitive functions. Boundary extension (BE) is a robust indicator of fast, automatic, and implicit scene construction. BE occurs when individuals who are viewing scenes automatically imagine what might be beyond the view, and consequently later misremember having seen a greater expanse of the scene. Patients with hippocampal damage show attenuated BE because of their scene construction impairment. In the current study, we administered BE tasks to patients with vmPFC damage, brain-damaged control patients, and healthy control participants. We also contrasted the performance of these patients to the previously-published data from patients with hippocampal lesions (Mullally, Intraub, & Maguire, 2012). We found that vmPFC-damaged patients showed reduced BE compared to brain-damaged and healthy controls. Indeed, BE attenuation was similar following vmPFC or hippocampal damage. Notably, however, whereas hippocampal damage seems to particularly impair the spatial coherence of scenes, vmPFC damage leads to a difficulty constructing scenes in a broader sense, with the prediction of what should be in a scene, and the monitoring or integration of the scene elements being particularly compromised. We conclude that vmPFC and hippocampus play important and complementary roles in scene construction.
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Damage to the Ventromedial Prefrontal Cortex reduces interpersonal disgust
Social cognitive and affective neuroscience, 2012Co-Authors: Elisa Ciaramelli, Rebecca G. Sperotto, Flavia Mattioli, Giuseppe Di PellegrinoAbstract:Disgust for contaminating objects (core disgust), immoral behaviors (moral disgust) and unsavory others (interpersonal disgust), have been assumed to be closely related. It is not clear, however, whether different forms of disgust are mediated by overlapping or specific neural substrates. We report that 10 patients with damage to the Ventromedial Prefrontal Cortex (vmPFC) avoided behaviors that normally elicit interpersonal disgust (e.g. using the scarf of a busker) less frequently than healthy and brain-damaged controls, whereas they avoided core and moral disgust elicitors at normal rates. These results indicate that different forms of disgust are dissociated neurally. We propose that the vmPFC is causally (and selectively) involved in mediating interpersonal disgust, shaping patterns of social avoidance and approach.
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Ventromedial Prefrontal Cortex and the Future of Morality
Emotion Review, 2011Co-Authors: Elisa Ciaramelli, Giuseppe Di PellegrinoAbstract:The Ventromedial Prefrontal Cortex (VMPFC) is crucial for moral behavior, yet the mechanism through which the VMPFC promotes moral behavior remains unclear. In this article, we emphasize that moral choice is often intertemporal, requiring foregoing short-term gains in favor of future outcomes of larger value. We propose that the VMPFC may be necessary for mental time travel (MTT), a cognitive process enabling vivid preexperiencing of future outcomes. By providing anticipated outcomes that inform decisions, MTT may promote farsighted, moral behaviors.
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The role of Ventromedial Prefrontal Cortex in navigation: a case of impaired wayfinding and rehabilitation.
Neuropsychologia, 2007Co-Authors: Elisa CiaramelliAbstract:A patient with Ventromedial Prefrontal damage, LG, is described who had a severe difficulty in wayfinding in his home town, despite intact knowledge for landmarks and routes in town. Although able to recall his spatial goals, LG often headed to familiar, "attractor" locations while navigating, losing his way in the process. Both a laboratory and an ecological study showed that spatial navigation improved when the patient was periodically reminded of, or asked to recall, the goal destination along his route. It is suggested that the Ventromedial Prefrontal Cortex is necessary to maintain actively the goal destination in working memory, for use in navigation.
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Selective deficit in personal moral judgment following damage to Ventromedial Prefrontal Cortex
Social Cognitive and Affective Neuroscience, 2007Co-Authors: Elisa Ciaramelli, Michela Muccioli, Elisabetta Làdavas, Giuseppe Di PellegrinoAbstract:Recent fMRI evidence has detected increased medial Prefrontal activation during contemplation of personal moral dilemmas compared to impersonal ones, which suggests that this cortical region plays a role in personal moral judgment. However, functional imaging results cannot definitively establish that a brain area is necessary for a particular cognitive process. This requires evidence from lesion techniques, such as studies of human patients with focal brain damage. Here, we tested 7 patients with lesions in the Ventromedial Prefrontal Cortex and 12 healthy individuals in personal moral dilemmas, impersonal moral dilemmas and non-moral dilemmas. Compared to normal controls, patients were more willing to judge personal moral violations as acceptable behaviors in personal moral dilemmas, and they did so more quickly. In contrast, their performance in impersonal and non-moral dilemmas was comparable to that of controls. These results indicate that the Ventromedial Prefrontal Cortex is necessary to oppose personal moral violations, possibly by mediating anticipatory, self-focused, emotional reactions that may exert strong influence on moral choice and behavior.
Eleanor A. Maguire - One of the best experts on this subject based on the ideXlab platform.
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Boundary extension is attenuated in patients with Ventromedial Prefrontal Cortex damage.
Cortex; a journal devoted to the study of the nervous system and behavior, 2018Co-Authors: Flavia De Luca, Eleanor A. Maguire, Cornelia Mccormick, Sinéad L. Mullally, Helene Intraub, Elisa CiaramelliAbstract:Abstract The Ventromedial Prefrontal Cortex (vmPFC) and hippocampus have been implicated in the mental construction of scenes and events. However, little is known about their specific contributions to these cognitive functions. Boundary extension (BE) is a robust indicator of fast, automatic, and implicit scene construction. BE occurs when individuals who are viewing scenes automatically imagine what might be beyond the view, and consequently later misremember having seen a greater expanse of the scene. Patients with hippocampal damage show attenuated BE because of their scene construction impairment. In the current study, we administered BE tasks to patients with vmPFC damage, brain-damaged control patients, and healthy control participants. We also contrasted the performance of these patients to the previously-published data from patients with hippocampal lesions (Mullally, Intraub, & Maguire, 2012). We found that vmPFC-damaged patients showed reduced BE compared to brain-damaged and healthy controls. Indeed, BE attenuation was similar following vmPFC or hippocampal damage. Notably, however, whereas hippocampal damage seems to particularly impair the spatial coherence of scenes, vmPFC damage leads to a difficulty constructing scenes in a broader sense, with the prediction of what should be in a scene, and the monitoring or integration of the scene elements being particularly compromised. We conclude that vmPFC and hippocampus play important and complementary roles in scene construction.
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Nonmonotonic recruitment of Ventromedial Prefrontal Cortex during remote memory recall
PLoS biology, 2018Co-Authors: Daniel N. Barry, Martin J. Chadwick, Eleanor A. MaguireAbstract:Systems-level consolidation refers to the time-dependent reorganisation of memory traces in the neoCortex, a process in which the Ventromedial Prefrontal Cortex (vmPFC) has been implicated. Capturing the precise temporal evolution of this crucial process in humans has long proved elusive. Here, we used multivariate methods and a longitudinal functional magnetic resonance imaging (fMRI) design to detect, with high granularity, the extent to which autobiographical memories of different ages were represented in vmPFC and how this changed over time. We observed an unexpected time course of vmPFC recruitment during retrieval, rising and falling around an initial peak of 8-12 months, before reengaging for older 2- and 5-year-old memories. This pattern was replicated in 2 independent sets of memories. Moreover, it was further replicated in a follow-up study 8 months later with the same participants and memories, for which the individual memory representations had undergone their hypothesised strengthening or weakening over time. We conclude that the temporal engagement of vmPFC in memory retrieval seems to be nonmonotonic, revealing a complex relationship between systems-level consolidation and Prefrontal Cortex recruitment that is unaccounted for by current theories.
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non monotonic recruitment of Ventromedial Prefrontal Cortex during remote memory recall
bioRxiv, 2018Co-Authors: Daniel N. Barry, Martin J. Chadwick, Eleanor A. MaguireAbstract:Systems-level consolidation refers to the time-dependent reorganisation of memory traces in the neoCortex, a process in which the Ventromedial Prefrontal Cortex (vmPFC) has been implicated. Capturing the precise temporal evolution of this crucial process in humans has long proved elusive. Here, we used multivariate methods and a longitudinal functional MRI design to detect, with high granularity, the extent to which autobiographical memories of different ages were represented in vmPFC and how this changed over time. We observed an unexpected time-course of vmPFC recruitment during retrieval, rising and falling around an initial peak of 8-12 months, before re-engaging for older two and five year old memories. This pattern was replicated in two independent sets of memories. Moreover, it was further replicated in a follow-up study eight months later with the same participants and memories, where the individual memory representations had undergone their hypothesised strengthening or weakening over time. We conclude that the temporal engagement of vmPFC in memory retrieval seems to be non-monotonic, revealing a complex relationship between systems-level consolidation and Prefrontal Cortex recruitment that is unaccounted for by current theories.
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Ventromedial Prefrontal Cortex drives hippocampal theta oscillations induced by mismatch computations
NeuroImage, 2015Co-Authors: Marta I Garrido, Eleanor A. Maguire, Dharshan Kumaran, Gareth R Barnes, Raymond J DolanAbstract:Detecting environmental change is fundamental for adaptive behavior in an uncertain world. Previous work indicates the hippocampus supports the generation of novelty signals via implementation of a match–mismatch detector that signals when an incoming sensory input violates expectations based on past experience. While existing work has emphasized the particular contribution of the hippocampus, here we ask which other brain structures also contribute to match–mismatch detection. Furthermore, we leverage the fine-grained temporal resolution of magnetoencephalography (MEG) to investigate whether mismatch computations are spectrally confined to the theta range, based on the prominence of this range of oscillations in models of hippocampal function. By recording MEG activity while human subjects perform a task that incorporates conditions of match–mismatch novelty we show that mismatch signals are confined to the theta band and are expressed in both the hippocampus and Ventromedial Prefrontal Cortex (vmPFC). Effective connectivity analyses (dynamic causal modeling) show that the hippocampus and vmPFC work as a functional circuit during mismatch detection. Surprisingly, our results suggest that the vmPFC drives the hippocampus during the generation and processing of mismatch signals. Our findings provide new evidence that the hippocampal–vmPFC circuit is engaged during novelty processing, which has implications for emerging theories regarding the role of vmPFC in memory.
