Early Amygdala Activation and Later Ventromedial Prefrontal Cortex Activation During Anger Induction and Imagery

2020 ◽  
Vol 1 (1) ◽  
pp. 1-8
Author(s):  
Darin D. Dougherty ◽  
Tina Chou ◽  
Ulrike Buhlmann ◽  
Scott L. Rauch ◽  
Thilo Deckersbach
Keyword(s):  
Prefrontal Cortex ◽  
Time Course ◽  
A Priori ◽  
Region Of Interest ◽  
Ventromedial Prefrontal Cortex ◽  
Amygdala Activation ◽  
Positron Emission ◽  
Initial Onset ◽  
The Individual ◽  
Neutral Conditions

Background: Neurobiological studies implicate the amygdala and related limbic/paralimbic structures, such as the ventromedial prefrontal cortex (VMPFC), in anger and aggression. Previous studies of self-generated anger using Positron Emission Tomography (PET) have consistently documented a lack of amygdala activation during anger. Objective: We investigated the hypothesis that a lack of amygdala activation during anger is due to differences in the time course of amygdala and VMPFC activation. Specifically, we explored whether the amygdala is involved in the early phases of anger experience which is later followed by increased VMPFC activation. Methods: Eighteen healthy control participants underwent fMRI. We adapted an anger induction paradigm previously used in our PET study, in which neutral and angry states were induced using autobiographical scripts. The hypothesized time course of amygdala and VMPFC activation during acute anger induction and imagery were modeled. Region of interest (ROI) analyses were used to identify significant a priori region activation, and correlations were run between signal values and VAS anger ratings. Results: Amygdala activation increased during the acute phase of anger induction and decreased during the later phase of anger imagery, whereas VMPFC activation decreased during anger induction and increased during anger imagery, compared to the neutral conditions. In addition, negative correlations were found between self-ratings of anger and bilateral VMPFC activation. Conclusions: Overall, our results suggest that the amygdala may be active at the initial onset of anger while the VMPFC is activated over time as the individual sustains and perhaps regulates that emotional state.

scholarly journals Effects of Blood Flow on [11C]Raclopride Binding in the Brain: Model Simulations and Kinetic Analysis of PET Data

1994 ◽  
Vol 14 (6) ◽  
pp. 995-1010 ◽  
Author(s):  
Jean Logan ◽  
Nora D. Volkow ◽  
Joanna S. Fowler ◽  
Gene-Jack Wang ◽  
Stephen L. Dewey ◽  
...  
Keyword(s):  
Blood Flow ◽  
Region Of Interest ◽  
Receptor Occupancy ◽  
Compartment Model ◽  
Model Parameters ◽  
Individual Model ◽  
Positron Emission ◽  
D2 Antagonist ◽  
The Stability ◽  
The Individual

To assess the stability of different measures of receptor occupancy from [11C]raclopride (a D2 antagonist) studies with positron emission tomography, we analyze data from five test/retest studies in normal volunteers in terms of individual model parameters from a three-compartment model, the distribution volume (DV) and the ratio of DVs from a receptor-containing region of interest to a non-receptor-containing region. Large variations were found in the individual model parameters, limiting their usefulness as an indicator of change in receptor systems. The DV ratio showed the smallest variation. Individual differences were reflected in the greater intersubject variation in DV than intrasubject variation. The potential effects of blood flow on these measurements were addressed both experimentally and by simulation studies using three models that explicitly incorporate blood flow into a compartmental model that also includes receptor–ligand binding. None of the models showed any variation in the DV with changes in blood flow as long as flow was held constant during the simulation. Experimentally, blood flow was significantly reduced by hyperventilation in a human subject. The DV was found to be reduced relative to baseline in the hyperventilation study, but the DV ratio remained unchanged. The effect of elevated and reduced flow was also tested in two baboon experiments in which Pco2 was varied. Some variability in the DV ratio was observed but was not correlated with changes in blood flow. This raises the possibility that other factors indirectly related to changes in blood flow (or Pco2) may cause changes in DV, and these effects need to be considered when evaluating experimental results.

Circadian disruption in mice through chronic jetlag-like conditions modulates molecular profiles of cancer in nucleus accumbens and prefrontal cortex

2021 ◽  
Author(s):  
Suliman Khan ◽  
V Wee Yong ◽  
Mengzhou Xue
Keyword(s):  
Prefrontal Cortex ◽  
Nucleus Accumbens ◽  
Pet Imaging ◽  
Biological Rhythms ◽  
Brain Regions ◽  
Molecular Signature ◽  
Environmental Light ◽  
Positron Emission ◽  
The Individual ◽  
Risk Of Cancer

Abstract Biological rhythms regulate physiological activities. Shiftwork disrupts normal circadian rhythms and may increase the risk of cancer through unknown mechanisms. To mimic environmental light/dark changes encountered by shift workers, a protocol called “chronic jet lag (CJL)” induced by repeatedly shifting light-dark cycles has been used. Here, we subjected mice to CJL by advancing light–dark cycle by 6 hours every 2 days, and conducted RNA sequencing to analyze the expression profile and molecular signature in the brain areas of prefrontal cortex and nucleus accumbens. We also performed positron emission tomography (PET) imaging to monitor changes related to glucose metabolism in brain. Our results reveal systematic reprogramming of gene expression associated with cancer related pathways and metabolic pathways in prefrontal cortex and nucleus accumbens. PET imaging indicates that glucose uptake level was significantly reduced in whole brain as well as the individual brain regions. Moreover, qPCR analysis describes that the expression levels of cancer related genes were altered in prefrontal cortex and nucleus accumbens. Overall, these results suggest a molecular and metabolic link with CJL mediated cancer risk, and generate hypotheses on how CJL increases the susceptibility to cancer.

Brainstem changes in 5-HT1A receptor availability during migraine attack

Cephalalgia ◽  
2010 ◽  
Vol 31 (1) ◽  
pp. 84-94 ◽  
Author(s):  
G Demarquay ◽  
A Lothe ◽  
JP Royet ◽  
N Costes ◽  
G Mick ◽  
...  
Keyword(s):  
Migraine Attack ◽  
Early Stage ◽  
Region Of Interest ◽  
Binding Potential ◽  
Precentral Gyrus ◽  
Individual Level ◽  
Control Subjects ◽  
Pet Tracer ◽  
Positron Emission ◽  
The Individual

Background: Among serotonin receptors, 5-HT1A receptors are implicated in the regulation of central serotoninergic tone and could be involved in the abnormal brain 5-HT turnover suspected in migraineurs. The aim of this study was to investigate 5-HT1A receptors’ availability during migraine attacks. Methods: Ten patients suffering from odor-triggered migraine attacks and 10 control subjects were investigated using positron emission tomography (PET) and [18F]MPPF PET tracer, a selective 5-HT1A antagonist. All subjects underwent calibrated olfactory stimulations prior to the PET study. Results: Four patients developed a migraine attack during the PET study. In these patients, statistical parametrical mapping and region of interest analyses showed an increased [18F]MPPF binding potential (BPND) in the pontine raphe when compared to headache-free migraineurs and control subjects. This ictal change was confirmed at the individual level in each of the four affected patients. In comparison with the headache-free migraineurs, patients with a migraine attack also showed significantly increased [18F]MPPF BPND in the left orbitofrontal cortex, precentral gyrus and temporal pole. No significant change in [18F]MPPF BPND was observed between headache-free migraineurs and controls. Conclusions: Our results emphasize the role of 5HT1A receptors in the pontine raphe nuclei during the early stage of migraine attacks.

scholarly journals The effect of functionally-guided-connectivity-based rTMS on amygdala activation

2020 ◽  
Author(s):  
L. Beynel ◽  
E. Campbell ◽  
M. Naclerio ◽  
J.T. Galla ◽  
A. Ghosal ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Interaction Analysis ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
A Priori ◽  
Video Clips ◽  
Amygdala Activation ◽  
Connected Node ◽  
Amygdala Activity ◽  
Psychophysiological Interaction ◽  
Electric Field Penetration

AbstractRepetitive transcranial magnetic stimulation (rTMS) has fundamentally transformed how we treat psychiatric disorders, but is still in need of innovation to optimally correct dysregulation that occurs throughout the fronto-limbic network. rTMS is often applied over the prefrontal cortex, a central node in this network, but less attention is given to subcortical areas because they lie at depths beyond the electric field penetration of rTMS. Recent studies have demonstrated that the effectiveness of rTMS is dependent on the functional connectivity between deep subcortical areas and superficial targets, indicating that leveraging such connectivity may improve dosing approaches for rTMS interventions. The current preliminary study, therefore, sought to test whether task-related, fMRI-connectivity-based rTMS could be used to modulate amygdala activation through its connectivity with the medial prefrontal cortex (mPFC). For this purpose, fMRI was collected on participants to identify a node in the mPFC that showed the strongest negative connectivity with right amygdala, as defined by psychophysiological interaction analysis. To promote long-lasting Hebbian-like effects, and potentially stronger modulation, 5Hz rTMS was then applied to this target as participants viewed frightening video-clips that engaged the fronto-limbic network. Post-rTMS fMRI results revealed promising increases in both the left mPFC and right amygdala, for active rTMS compared to sham. While these modulatory findings are promising, they differ from the a priori expectation that excitatory 5Hz rTMS over a negatively connected node would reduce amygdala activity. As such, further research is needed to better understand how connectivity influences TMS effects on distal structures, and to leverage this information to improve therapeutic applications.

The speed of morality: a high-density electrical neuroimaging study

2012 ◽  
Vol 108 (11) ◽  
pp. 3068-3072 ◽  
Author(s):  
Jean Decety ◽  
Stephanie Cacioppo
Keyword(s):  
Prefrontal Cortex ◽  
Current Source ◽  
Event Related Potentials ◽  
High Density ◽  
Ventromedial Prefrontal Cortex ◽  
Affective States ◽  
Related Potentials ◽  
The Individual ◽  
The Right ◽  
Computational Systems

Neuroscience research indicates that moral reasoning is underpinned by distinct neural networks including the posterior superior temporal sulcus (pSTS), amygdala, and ventromedial prefrontal cortex, which support communication between computational systems underlying affective states, cognitions, and motivational processes. To characterize real-time neural processing underpinning moral computations, high-density event-related potentials were measured in participants while they viewed short, morally laden visual scenarios depicting intentional and accidental harmful actions. Current source density maxima in the right pSTS as fast as 62 ms poststimulus first distinguished intentional vs. accidental actions. Responses in the amygdala/temporal pole (122 ms) and ventromedial prefrontal cortex (182 ms) were then evoked by the perception of harmful actions, indicative of fast information processing associated with early stages of moral cognition. Our data strongly support the notion that intentionality is the first input to moral computations. They also demonstrate that emotion acts as a gain antecedent to moral judgment by alerting the individual to the moral salience of a situation and provide evidence for the pervasive role of affect in moral sensitivity and reasoning.

scholarly journals Fatty acid amide hydrolase binding is inversely correlated with amygdalar functional connectivity: a combined positron emission tomography and magnetic resonance imaging study in healthy individuals

2021 ◽  
Vol 46 (2) ◽  
Author(s):  
Duncan G.J. Green ◽  
Jinhee Kim ◽  
Stephen J. Kish ◽  
Rachel F. Tyndale ◽  
Matthew N. Hill ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Prefrontal Cortex ◽  
Functional Connectivity ◽  
Fatty Acid Amide Hydrolase ◽  
Acid Amide ◽  
Ventromedial Prefrontal Cortex ◽  
Emission Tomography ◽  
Positron Emission ◽  
Amide Hydrolase ◽  
Fatty Acid Amide

Background: Upregulation of the endocannabinoid enzyme fatty acid amide hydrolase (FAAH) has been linked to abnormal activity in frontoamygdalar circuits, a hallmark of posttraumatic stress disorder. We tested the hypothesis that FAAH levels in the amygdala were negatively correlated with functional connectivity between the amygdala and prefrontal cortex, subserving stress and affect control. Methods: Thirty-one healthy participants completed positron emission tomography (PET) imaging with the FAAH probe [C-11]CURB, and resting-state functional MRI scans. Participants were genotyped for the FAAH polymorphism rs324420, and trait neuroticism was assessed. We calculated amygdala functional connectivity using predetermined regions of interest (including the subgenual ventromedial prefrontal cortex [sgvmPFC] and the dorsal anterior cingulate cortex [dACC]) and a seed-to-voxel approach. We conducted correlation analyses on functional connectivity, with amygdala [C-11]CURB binding as a variable of interest. Results: The strength of amygdala functional connectivity with the sgvmPFC and dACC was negatively correlated with [C-11]CURB binding in the amygdala (sgvmPFC: r = −0.38, q = 0.04; dACC: r = –0.44; q = 0.03). Findings were partly replicated using the seed-to-voxel approach, which showed a cluster in the ventromedial prefrontal cortex, including voxels in the dACC but not the sgvmPFC (cluster-level, family-wise error rate corrected p < 0.05). Limitations: We did not replicate earlier findings of a relationship between an FAAH polymorphism (rs324420) and amygdala functional connectivity. Conclusion: Our data provide preliminary evidence that lower levels of FAAH in the amygdala relate to increased frontoamygdalar functional coupling. Our findings were consistent with the role of FAAH in regulating brain circuits that underlie fear and emotion processing in humans.

scholarly journals Decision value signals in the ventromedial prefrontal cortex and anhedonia across mood and psychotic disorders

2020 ◽  
Author(s):  
Min Su Kang ◽  
Daniel H. Wolf ◽  
Rebecca Kazinka ◽  
Sangil Lee ◽  
Kosha Ruparel ◽  
...  
Keyword(s):  
Decision Making ◽  
Prefrontal Cortex ◽  
Negative Symptoms ◽  
Psychotic Disorders ◽  
A Priori ◽  
Primary Diagnosis ◽  
Ventromedial Prefrontal Cortex ◽  
Imaging Data ◽  
Prominent Symptom ◽  
History Of

AbstractBackgroundAnhedonia, or diminished pleasure, is a prominent symptom in mood and psychotic disorders. Anticipatory pleasure is particularly impaired in these conditions, which may be reflected in blunted activity in the fronto-striatal circuitry during evaluation of future rewards. This study examined the neural correlates of anhedonia during decision-making across mood and psychotic disorders.MethodsAnalyses included 81 adults with major depression (N=17), bipolar disorder (in depressed state, N=21), schizophrenia (N=23), or no history of psychopathology (N=20). Participants performed a delay discounting paradigm while functional imaging data were acquired at 3T. We examined the relationship between anhedonia and activity in two a priori regions of interest critical for valuation, the ventromedial prefrontal cortex (vmPFC) and ventral striatum. Anhedonia was measured using a semi-structured clinical interview; cognition, depression, and symptoms of psychosis were also evaluated.ResultsDiscounting behavior did not differ as function of primary diagnosis or level of anhedonia (F(3,77) = 0.28, p = 0.84; r = 0.03, p = 0.78). Value-related activity in the vmPFC was blunted in association with anhedonia (β = −0.27; 95% CI, −0.48 to −0.06; p = 0.01). This relationship remained significant while controlling for primary diagnosis, behavioral performance, cognitive functioning, smoking, depression severity, and both positive and negative symptoms of schizophrenia.ConclusionsHypofunction in the vmPFC during decision-making about future rewards is specifically linked to anhedonia, rather than a general feature of psychopathology. These findings help elucidate the pathophysiological underpinnings of anhedonia across mood and psychotic disorders and inform the development of novel treatment approaches.

scholarly journals Non-monotonic recruitment of ventromedial prefrontal cortex during remote memory recall

2017 ◽  
Author(s):  
Daniel N. Barry ◽  
Martin J. Chadwick ◽  
Eleanor A. Maguire
Keyword(s):  
Prefrontal Cortex ◽  
Time Course ◽  
Brain Activity ◽  
Activity Patterns ◽  
Ventromedial Prefrontal Cortex ◽  
Remote Memory ◽  
Autobiographical Memories ◽  
Temporal Profile ◽  
Different Ages ◽  
Over Time

AbstractSystems-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.Author SummaryOur past experiences are captured in autobiographical memories which allow us to recollect events from our lives long after they originally occurred. A part of the brain’s frontal lobe, called the ventromedial prefrontal cortex or vmPFC, is known to be important for supporting autobiographical memories especially as memories become more remote. The precise temporal profile of the vmPFC’s involvement is unclear, yet this information is vital if we are to understand how memories change over time and the mechanisms involved. In this study we sought to establish the time-course of vmPFC engagement in the recollection of autobiographical memories while participants recalled memories of different ages during functional magnetic resonance imaging (fMRI). Using a method that detects brain activity patterns associated with individual memories, we found that memory-specific neural patterns in vmPFC became more distinct over the first few months after a memory was formed, but then this initial involvement of vmPFC subsided after one year. However, more remote memories (two years and older), appeared to re-engage vmPFC once again. This temporal profile is difficult to accommodate within any single existing theory. Consequently, our results provoke a re-think about how memories evolve over time and the role played by the vmPFC.

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