PURPOSE: To systematically evaluate and quantify the effects of Tai Chi/Qigong (TCQ) on motor (UPDRS III, balance, falls, Timed-Up-and-Go, and 6-Minute Walk) and non-motor (depression and cognition) function, and quality of life (QOL) in patients with Parkinson's disease (PD).METHODS: A systematic search in 7 electronic databases targeted clinical studies evaluating TCQ for individuals with PD published through August 2016. Meta-analysis was used to estimate effect sizes (Hedges's g) and publication bias for randomized controlled trials (RCTs). Methodological bias in RCTs was assessed by two raters.
RESULTS: Our search identified 21 studies, 15 of which were RCTs with a total of 735 subjects. For RCTs, comparison groups included no treatment (n = 7, 47%) and active interventions (n = 8, 53%). Duration of TCQ ranged from 2 to 6 months. Methodological bias was low in 6 studies, moderate in 7, and high in 2. Fixed-effect models showed that TCQ was associated with significant improvement on most motor outcomes (UPDRS III [ES = -0.444, p < 0.001], balance [ES = 0.544, p < 0.001], Timed-Up-and-Go [ES = -0.341, p = 0.005], 6 MW [ES = -0.293, p = 0.06], falls [ES = -0.403, p = 0.004], as well as depression [ES = -0.457, p = 0.008] and QOL [ES = -0.393, p < 0.001], but not cognition [ES = -0.225, p = 0.477]). I2 indicated limited heterogeneity. Funnel plots suggested some degree of publication bias.
CONCLUSION: Evidence to date supports a potential benefit of TCQ for improving motor function, depression and QOL for individuals with PD, and validates the need for additional large-scale trials.
A current limitation for imaging of brain function is the potential confound of anatomical differences or registration error, which may manifest via apparent functional "activation" for between-subject analyses. With respect to functional activations, underlying tissue mismatches can be regarded as a nuisance variable. We propose adding the probability of gray matter at a given voxel as a covariate (nuisance variable) in the analysis of voxelwise multisubject functional data using standard statistical techniques. A method is presented to assess the extent to which a functional activation can reliably be explained by underlying anatomical differences, and simultaneously, to assess the component of the functional activation which cannot be attributed to anatomical difference and thus is likely due to functional difference alone. Extension of the method to other intermodal imaging applications is discussed. Two exemplary data sets, one PET and one fMRI, are used to demonstrate the implementation and utility of this method, which apportions the relative contributions of anatomy and function for an apparent functional activation. The examples show two distinct types of results. First, a so-called functional activation may actually be caused by a systematic anatomical difference which, when modeled, diminishes the functional effect. In the second result type, including the anatomical differences in the model can account for a large component of otherwise unmodeled variance, yielding an increase in the functional effect cluster size and/or magnitude. In either case, ignoring the readily available structural information can lead to misinterpretation of functional results.
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It has been argued that emotion, pain, and cognitive control are functionally segregated in distinct subdivisions of the cingulate cortex. But recent observations encourage a fundamentally different view. Imaging studies indicate that negative affect, pain, and cognitive control activate an overlapping region of dorsal cingulate, the anterior midcingulate cortex (aMCC). Anatomical studies reveal that aMCC constitutes a hub where information about reinforcers can be linked to motor centers responsible for expressing affect and executing goal-directed behavior. Computational modeling and other kinds of evidence suggest that this intimacy reflects control processes that are common to all three domains. These observations compel a reconsideration of dorsal cingulate’s contribution to negative affect and pain.
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This article examines the Kentucky Initiative for Social Skill and Emotional Development which provides annual training and technical assistance to build early childhood programs' capacity to deliver practices known to promote social and emotional competency. The initiative is based on the 3-tiered Positive Behavior Support model that teaches educators to both prevent and intervene with challenging behaviors. The training and technical assistance components of this initiative are described as well as limitations of the current initiative and recommendations for implementation in other states. (Contains 2 figures and 1 table.)
"The Legacy of Menla is a fresh portrayal of Tibetan Medicine through the eyes of three Indian women who have been diagnosed with different stages of cancer. Often acting against their families’ wishes or the advice of Western doctors, they chose to put their faith in Tibetan doctors and change their lives. In the intersection of Buddhism and science, Tibetan Medicine has a peculiar place in the field of healing that speaks to both believers and nonbelievers. Apart from the patients’ perspectives, the film takes us through the process of medicine making in the Himalayas and shows us the education of upcoming doctors. With the help of established Tibetan healers we will see the past, present and future of this healing system."--Synopsis from Arrabona Studio: http://arrabonastudio.hu/portfolio/legacyofmenla/
Humans show consistent differences in the extent to which their behavior reflects a bias toward appetitive approach-related behavior or avoidance of aversive stimuli [Elliot, A. J. Approach and avoidance motivation. In A. J. Elliot (Ed.), Handbook of approach and avoidance motivation (pp. 3-14). New York: Psychology Press, 2008]. We examined the hypothesis that in healthy participants this motivational bias (assessed by self-report and by a probabilistic learning task that allows direct comparison of the relative sensitivity to reward and punishment) reflects lateralization of dopamine signaling. Using [F-18]fallypride to measure D2/D3 binding, we found that self-reported motivational bias was predicted by the asymmetry of frontal D2 binding. Similarly, striatal and frontal asymmetries in D2 dopamine receptor binding, rather than absolute binding levels, predicted individual differences in learning from reward versus punishment. These results suggest that normal variation in asymmetry of dopamine signaling may, in part, underlie human personality and cognition.
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BACKGROUND AND OBJECTIVES: Managing stress is very important for first-year college students adjusting to undergraduate life. Aspects of emotion regulation, including mindfulness and the ability to regulate distressing emotion adaptively, often correlate positively with well-being. However, little research has examined overlapping and/or distinct effects of these constructs in predicting changes in adjustment over a stressful transition. Thus, the present study examined the contributions of mindfulness and adaptive emotion regulation abilities in maintaining well-being during the transition to college. We further examined experience with mind-body practices, which may promote mindfulness and positive adjustment.DESIGN: Online surveys were administered to 158 undergraduates near the beginning and end of their first semester.
METHODS: Near semester start and end, students reported levels of mindfulness, adaptive emotion regulation abilities, emotional and spiritual well-being, and experience with mind-body practices.
RESULTS: Compared to mindfulness, adaptive emotion regulation abilities largely demonstrated stronger cross-sectional and longitudinal associations with well-being. However, mindfulness uniquely protected against changes in depression for students with greater emotion regulation difficulties. Over half of participants reported having tried mind-body practices, but just 1% reported current use.
CONCLUSIONS: Promoting mindfulness practices and adaptive emotion regulation abilities at the start of college may build resilience in undergraduate students.
We aimed to evaluate whether mindfulness-based cognitive therapy (MBCT) was feasible and acceptable for young people, their parents and the clinicians working with them; whether a parallel course for parents was a useful addition; and whether attendance at MBCT was associated with improved outcomes. The design was a mixed-method service evaluation of an eight-session MBCT programme for young people who were recovering from depression. The course was a manualised eight-session group intervention. Both young people (n = 18) and parents (n = 21) completed validated measures before and after the course. Semi-structured interviews were completed with some group participants and clinical staff working in the service. Care records were searched for additional contact following the intervention. Qualitative data from young people, parents and clinicians suggested that MBCT was acceptable and feasible and provided strategies to cope. The parent course was reported to provide personal support to parents and helped them cope with their child’s depression whilst also impacting the family, promoted shared understanding of depression and strategies to combat it and addressed intergenerational aspects of depression. Eighty-four per cent of participants attended at least 6/8 sessions, and 48% required no further intervention within the following year. Young people had statistically significant improvements across all outcome measures, whilst parents had statistically significant improvements in rumination, self-compassion and decentring.
Dispositional mindfulness is often linked to higher positive affect and lower negative affect, and coping with stress has been hypothesized to mediate these links. However, few studies have explicitly tested the ways in which stress appraisals, coping strategies, or coping flexibility (i.e., fit of coping to controllability appraisals) uniquely relate to mindfulness and well-being. Drawing on a stress and coping framework, the present study tested the degree to which (a) lower stress appraisals mediate mindfulness' effects on daily positive and negative affect; (b) daily coping mediates mindfulness' impact on daily positive and negative affect, above and beyond the effects of stress appraisals; and (c) coping flexibility mediates mindfulness' impact on positive and negative affect, above and beyond the effects of stress appraisals and average daily coping. Participants were 157 undergraduate students (mean age = 17.81; 79% women), completing daily diary questionnaires regarding stress appraisals, coping, and affect for 1 week. Results demonstrate that lower average stress appraisals mediated 19% of mindfulness' effects on negative affect; further, average use of some "mindful" emotion-focused coping strategies (i.e., non-self-blame and acceptance) independently mediated 3%-13% of mindfulness' effects on positive and negative affect. Although mindfulness was associated with greater "fit" of problem-focused versus acceptance coping to high controllability appraisals, coping flexibility did not appear to mediate mindfulness' effects on either positive or negative affect. Thus, mindfulness-based stress management interventions may be most effective by promoting mindful coping to complement, rather than replace, problem-focused coping. (PsycINFO Database Record
During the past two decades, mindfulness meditation has gone from being a fringe topic of scientific investigation to being an occasional replacement for psychotherapy, tool of corporate well-being, widely implemented educational practice, and “key to building more resilient soldiers.” Yet the mindfulness movement and empirical evidence supporting it have not gone without criticism. Misinformation and poor methodology associated with past studies of mindfulness may lead public consumers to be harmed, misled, and disappointed. Addressing such concerns, the present article discusses the difficulties of defining mindfulness, delineates the proper scope of research into mindfulness practices, and explicates crucial methodological issues for interpreting results from investigations of mindfulness. For doing so, the authors draw on their diverse areas of expertise to review the present state of mindfulness research, comprehensively summarizing what we do and do not know, while providing a prescriptive agenda for contemplative science, with a particular focus on assessment, mindfulness training, possible adverse effects, and intersection with brain imaging. Our goals are to inform interested scientists, the news media, and the public, to minimize harm, curb poor research practices, and staunch the flow of misinformation about the benefits, costs, and future prospects of mindfulness meditation.
The impact of using motion estimates as covariates of no interest was examined in general linear modeling (GLM) of both block design and rapid event-related functional magnetic resonance imaging (fMRI) data. The purpose of motion correction is to identify and eliminate artifacts caused by task-correlated motion while maximizing sensitivity to true activations. To optimize this process, a combination of motion correction approaches was applied to data from 33 subjects performing both a block-design and an event-related fMRI experiment, including analysis: (1) without motion correction; (2) with motion correction alone; (3) with motion-corrected data and motion covariates included in the GLM; and (4) with non-motion-corrected data and motion covariates included in the GLM. Inclusion of covariates was found to be generally useful for increasing the sensitivity of GLM results in the analysis of event-related data. When motion parameters were included in the GLM for event-related data, it made little difference if motion correction was actually applied to the data. For the block design, inclusion of motion covariates had a deleterious impact on GLM sensitivity when even moderate correlation existed between motion and the experimental design. Based on these results, we present a general strategy for block designs, event-related designs, and hybrid designs to identify and eliminate probable motion artifacts while maximizing sensitivity to true activations.
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Critical questions include: What is an emotion? How are emotions organized in the brain? How do emotion and cognition interact? How are emotions embodied in the social world? How and why are emotions communicated? How are emotions physically embodied? What develops in emotional development?
Children with an anxious temperament (AT) are at risk for developing psychiatric disorders along the internalizing spectrum, including anxiety and depression. Like these disorders, AT is a multidimensional phenotype and children with extreme anxiety show varying mixtures of physiological, behavioral, and other symptoms. Using a well-validated juvenile monkey model of AT, we addressed the degree to which this phenotypic heterogeneity reflects fundamental differences or similarities in the underlying neurobiology. The rhesus macaque is optimal for studying AT because children and young monkeys express the anxious phenotype in similar ways and have similar neurobiology. Fluorodeoxyglucose (FDG)-positron emission tomography (FDG-PET) in 238 freely behaving monkeys identified brain regions where metabolism predicted variation in three dimensions of the AT phenotype: hypothalamic-pituitary-adrenal (HPA) activity, freezing behavior, and expressive vocalizations. We distinguished brain regions that predicted all three dimensions of the phenotype from those that selectively predicted a single dimension. Elevated activity in the central nucleus of the amygdala and the anterior hippocampus was consistently found across individuals with different presentations of AT. In contrast, elevated activity in the lateral anterior hippocampus was selective to individuals with high levels of HPA activity, and decreased activity in the motor cortex (M1) was selective to those with high levels of freezing behavior. Furthermore, activity in these phenotype-selective regions mediated relations between amygdala metabolism and different expressions of anxiety. These findings provide a framework for understanding the mechanisms that lead to heterogeneity in the clinical presentation of internalizing disorders and set the stage for developing improved interventions.
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BACKGROUND: Anxious temperament (AT) is identifiable early in life and predicts the later development of anxiety disorders and depression. Neuropeptide Y (NPY) is a putative endogenous anxiolytic neurotransmitter that adaptively regulates responses to stress and might confer resilience to stress-related psychopathology. With a well-validated nonhuman primate model of AT, we examined expression of the NPY system in the central nucleus (Ce) of the amygdala, a critical neural substrate for extreme anxiety.
METHODS: In 24 young rhesus monkeys, we measured Ce messenger RNA (mRNA) levels of all members of the NPY system that are detectable in the Ce with quantitative real time polymerase chain reaction. We then examined the relationship between these mRNA levels and both AT expression and brain metabolism.
RESULTS: Lower mRNA levels of neuropeptide Y receptor 1 (NPY1R) and NPY5R but not NPY or NPY2R in the Ce predicted elevated AT; mRNA levels for NPY1R and NPY5R in the motor cortex were not related to AT. In situ hybridization analysis provided for the first time a detailed description of NPY1R and NPY5R mRNA distribution in the rhesus amygdala and associated regions. Lastly, mRNA levels for these two receptors in the Ce predicted metabolic activity in several regions that have the capacity to regulate the Ce.
CONCLUSIONS: Decreased NPY signaling in the Ce might contribute to the altered metabolic activity that is a component of the neural substrate underlying AT. This suggests that enhancement of NPY signaling might reduce the risk to develop psychopathology.
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In children, behavioral inhibition (BI) in response to potential threat predicts the development of anxiety and affective disorders, and primate lesion studies suggest involvement of the orbitofrontal cortex (OFC) in mediating BI. Lesion studies are essential for establishing causality in brain-behavior relationships, but should be interpreted cautiously because the impact of a discrete lesion on a complex neural circuit extends beyond the lesion location. Complementary functional imaging methods assessing how lesions influence other parts of the circuit can aid in precisely understanding how lesions affect behavior. Using this combination of approaches in monkeys, we found that OFC lesions concomitantly alter BI and metabolism in the bed nucleus of stria terminalis (BNST) region and that individual differences in BNST activity predict BI. Thus it appears that an important function of the OFC in response to threat is to modulate the BNST, which may more directly influence the expression of BI.
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Positive affect elicited in a mother toward her newborn infant may be one of the most powerful and evolutionarily preserved forms of positive affect in the emotional landscape of human behavior. This study examined the neurobiology of this form of positive emotion and in so doing, sought to overcome the difficulty of eliciting robust positive affect in response to visual stimuli in the physiological laboratory. Six primiparous human mothers with no indications of postpartum depression brought their infants into the laboratory for a photo shoot. Approximately 6 weeks later, they viewed photographs of their infant, another infant, and adult faces during acquisition of functional magnetic resonance images (fMRI). Mothers exhibited bilateral activation of the orbitofrontal cortex (OFC) while viewing pictures of their own versus unfamiliar infants. While in the scanner, mothers rated their mood more positively for pictures of their own infants than for unfamiliar infants, adults, or at baseline. The orbitofrontal activation correlated positively with pleasant mood ratings. In contrast, areas of visual cortex that also discriminated between own and unfamiliar infants were unrelated to mood ratings. These data implicate the orbitofrontal cortex in a mother's affective responses to her infant, a form of positive emotion that has received scant attention in prior human neurobiological studies. Furthermore, individual variations in orbitofrontal activation to infant stimuli may reflect an important dimension of maternal attachment.
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Where do spontaneous thoughts come from? It may be surprising that the seemingly straightforward answers "from the mind" or "from the brain" are in fact an incredibly recent understanding of the origins of spontaneous thought. For nearly all of human history, our thoughts - especially the most sudden, insightful, and important - were almost universally ascribed to divine or other external sources. Only in the past few centuries have we truly taken responsibility for their own mental content, and finally localized thought to the central nervous system - laying the foundations for a protoscience of spontaneous thought. But enormous questions still loom: what, exactly, is spontaneous thought? Why does our brain engage in spontaneous forms of thinking, and when is this most likely to occur? And perhaps the question most interesting and accessible from a scientific perspective: how does the brain generate and evaluate its own spontaneous creations? Spontaneous thought includes our daytime fantasies and mind-wandering; the flashes of insight and inspiration familiar to the artist, scientist, and inventor; and the nighttime visions we call dreams. This Handbook brings together views from neuroscience, psychology, philosophy, phenomenology, history, education, contemplative traditions, and clinical practice to begin to address the ubiquitous but poorly understood mental phenomena that we collectively call 'spontaneous thought.' In studying such an abstruse and seemingly impractical subject, we should remember that our capacity for spontaneity, originality, and creativity defines us as a species - and as individuals. Spontaneous forms of thought enable us to transcend not only the here and now of perceptual experience, but also the bonds of our deliberately-controlled and goal-directed cognition; they allow the space for us to be other than who we are, and for our minds to think beyond the limitations of our current viewpoints and beliefs.
Examined were electroencephalogram (EEG) asymmetries during the presence of discrete facial signs of emotion among 10-month-old infants who were tested in a standard stranger- and mother-approach paradigm that included a brief separation from mother. Data underscore the usefulness of EEG measures of hemispheric activation in differentiating among certain emotional states. (RH)
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Our outside world changes continuously, for example, when driving through traffic. An important question is how our brain deals with this constant barrage of rapidly changing sensory input and flexibly selects only newly goal-relevant information for further capacity-limited processing in working memory. The challenge our brain faces is experimentally captured by the attentional blink (AB): an impairment in detecting the second of two target stimuli presented in close temporal proximity among distracters. Many theories have been proposed to explain this deficit in processing goal-relevant information, with some attributing the AB to capacity limitations related to encoding of the first target and others assigning a critical role to on-line selection mechanisms that control access to working memory. The current study examined the role of striatal dopamine in the AB, given its known role in regulating the contents of working memory. Specifically, participants performed an AB task and their basal level of dopamine D2-like receptor binding was measured using PET and [F-18]fallypride. As predicted, individual differences analyses showed that greater D2-like receptor binding in the striatum was associated with a larger AB, implicating striatal dopamine and mechanisms that control access to working memory in the AB. Specifically, we propose that striatal dopamine may determine the AB by regulating the threshold for working memory updating, providing a testable physiological basis for this deficit in gating rapidly changing visual information. A challenge for current models of the AB lies in connecting more directly to these neurobiological data.
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Complementary and alternative medicine (CAM) treatments have been used for thousands of years around the world. There has been increased interest in utilizing CAM for menopausal symptoms since the release of results of the Women's Health Initiative elucidated long-term adverse effects associated with hormone therapy. Women looking for more natural or safer means to treat hot flushes, night sweats, and other menopausal symptoms often turn to CAM such as yoga, phytoestrogens, or black cohosh. Yet there have been few well-conducted studies looking at the efficacy of these treatments. This review examines randomized clinical trials, systematic reviews, and meta-analyses evaluating the effectiveness of commonly used CAM for the treatment of menopausal symptoms.
Compassion, the emotional response of caring for another who is suffering and that results in motivation to relieve suffering, is thought to be an emotional antecedent to altruistic behavior. However, it remains unclear whether compassion enhances altruistic behavior in a uniform way or is specific to sub-types of behavior such as altruistic helping of a victim or altruistic punishment of a transgressor. We investigated the relationship between compassion and subtypes of altruistic behavior using third-party paradigms where participants 1) witnessed an unfair economic exchange between a transgressor and a victim, and 2) had the opportunity to either spend personal funds to either economically a) help the victim or b) punish the transgressor. In Study 1, we examined whether individual differences in self-reported empathic concern (the emotional component of compassion) was associated with greater altruistic helping or punishment behavior in two independent samples. For participants who witnessed an unfair transaction, trait empathic concern was associated with greater helping of a victim and had no relationship to punishment. However, in those who decided to punish the transgressor, participants who reported greater empathic concern decided to punish less. In Study 2, we directly enhanced compassion using short-term online compassion meditation training to examine whether altruistic helping and punishment were increased after two weeks of training. Compared to an active reappraisal training control group, the compassion training group gave more to help the victim and did not differ in punishment of the transgressor. Together, these two studies suggest that compassion is related to greater altruistic helping of victims and is not associated with or may mitigate altruistic punishment of transgressors.
The serotonin transporter (5-HTT) plays a critical role in regulating serotonergic neurotransmission and is implicated in the pathophysiology of anxiety and affective disorders. Positron emission tomography scans using [(11)C]DASB [(11)C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile] to measure 5-HTT availability (an index of receptor density and binding) were performed in 34 rhesus monkeys in which the relationship between regional brain glucose metabolism and anxious temperament was previously established. 5-HTT availability in the amygdalohippocampal area and bed nucleus of the stria terminalis correlated positively with individual differences in a behavioral and neuroendocrine composite of anxious temperament. 5-HTT availability also correlated positively with stress-induced metabolic activity within these regions. Collectively, these findings suggest that serotonergic modulation of neuronal excitability in the neural circuitry associated with anxiety mediates the developmental risk for affect-related psychopathology.
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The length polymorphism of the serotonin (5-HT) transporter gene promoter region has been implicated in altered 5-HT function and, in turn, neuropsychiatric illnesses, such as anxiety and depression. The nonhuman primate has been used as a model to study anxiety-related mechanisms in humans based upon similarities in behavior and the presence of a similar 5-HT transporter gene polymorphism. Stressful and threatening contexts in the nonhuman primate model have revealed 5-HT transporter genotype dependent differences in regional glucose metabolism. Using the rhesus monkey, we examined the extent to which serotonin transporter genotype is associated with 5-HT transporter binding in brain regions implicated in emotion-related pathology.
METHODS: Genotype data and high resolution PET scans were acquired in 29 rhesus (Macaca mulatta) monkeys. [C-11]DASB dynamic PET scans were acquired for 90 min in the anesthetized animals and images of distribution volume ratio (DVR) were created to serve as a metric of 5-HT transporter binding for group comparison based on a reference region method of analysis. Regional and voxelwise statistical analysis were performed with corrections for anatomical differences in gray matter probability, sex, age and radioligand mass.
RESULTS: There were no significant differences when comparing l/l homozygotes with s-carriers in the regions of the brain implicated in anxiety and mood related illnesses (amygdala, striatum, thalamus, raphe nuclei, temporal and prefrontal cortex). There was a significant sex difference in 5-HT transporter binding in all regions with females having 18%-28% higher DVR than males.
CONCLUSIONS: Because these findings are consistent with similar genotype findings in humans, this further strengthens the use of the rhesus model for studying anxiety-related neuropathologies.
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A variant allele in the promoter region of the serotonin transporter gene, SLC6A4, the s allele, is associated with increased vulnerability to develop anxiety-related traits and depression. Furthermore, functional magnetic resonance imaging (fMRI) studies reveal that s carriers have increased amygdala reactivity in response to aversive stimuli, which is thought to be an intermediate phenotype mediating the influences of the s allele on emotionality. We used high-resolution microPET [18F]fluoro-2-deoxy-D-glucose (FDG) scanning to assess regional brain metabolic activity in rhesus monkeys to further explore s allele-related intermediate phenotypes. Rhesus monkeys provide an excellent model to understand mechanisms underlying human anxiety, and FDG microPET allows for the assessment of brain activity associated with naturalistic environments outside the scanner. During FDG uptake, monkeys were exposed to different ethologically relevant stressful situations (relocation and threat) as well as to the less stressful familiar environment of their home cage. The s carriers displayed increased orbitofrontal cortex activity in response to both relocation and threat. However, during relocation they displayed increased amygdala reactivity and in response to threat they displayed increased reactivity of the bed nucleus of the stria terminalis. No increase in the activity of any of these regions occurred when the animals were administered FDG in their home cages. These findings demonstrate context-dependent intermediate phenotypes in s carriers that provide a framework for understanding the mechanisms underlying the vulnerabilities of s-allele carriers exposed to different types of stressors.
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BACKGROUND: Hypothalamic-pituitary-adrenal (HPA) system activation is adaptive in response to stress, and HPA dysregulation occurs in stress-related psychopathology. It is important to understand the mechanisms that modulate HPA output, yet few studies have addressed the neural circuitry associated with HPA regulation in primates and humans. Using high-resolution F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in rhesus monkeys, we assessed the relation between individual differences in brain activity and HPA function across multiple contexts that varied in stressfulness.
METHODS: Using a logical AND conjunctions analysis, we assessed cortisol and brain metabolic activity with FDG-PET in 35 adolescent rhesus monkeys exposed to two threat and two home-cage conditions. To test the robustness of our findings, we used similar methods in an archival data set. In this data set, brain metabolic activity and cortisol were assessed in 17 adolescent male rhesus monkeys that were exposed to three stress-related contexts.
RESULTS: Results from the two studies revealed that subgenual prefrontal cortex (PFC) metabolism (Brodmann's area 25/24) consistently predicted individual differences in plasma cortisol concentrations regardless of the context in which brain activity and cortisol were assessed.
CONCLUSIONS: These findings suggest that activation in subgenual PFC may be related to HPA output across a variety of contexts (including familiar settings and novel or threatening situations). Individuals prone to elevated subgenual PFC activity across multiple contexts may be individuals who consistently show heightened cortisol and may be at risk for stress-related HPA dysregulation.
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