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To test the effects of cortisol on affective experience, the authors orally administered a placebo, 20 mg cortisol, or 40 mg cortisol to 85 men. Participants' affective responses to negative and neutral stimuli were measured. Self-reported affective state was also assessed. Participants in the 40-mg group (showing extreme cortisol elevations within the physiological range) rated neutral stimuli as more highly arousing than did participants in the placebo and 20-mg groups. Furthermore, within the 20-mg group, individuals with higher cortisol elevations made higher arousal ratings of neutral stimuli. However, cortisol was unrelated to self-reported affective state. Thus, findings indicate that acute cortisol elevations cause heightened arousal in response to objectively nonarousing stimuli, in the absence of effects on mood.
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Individuals with asthma have twice the risk of developing mood and anxiety disorders as individuals without asthma and these psychological factors are associated with worse outcomes and greater need for medical intervention. Similarly, asthma symptom onset and exacerbation often occur during times of increased psychological stress. Remission from depression, on the other hand, is associated with improvement in asthma symptoms and decreased usage of asthma medication. Yet research aimed at understanding the biological underpinnings of asthma has focused almost exclusively on the periphery. An extensive literature documents the relationship between emotion and asthma, but little work has explored the function of affective neural circuitry in asthma symptom expression. Therefore, the following review integrates neuroimaging research related to factors that may impact symptom expression in asthma, such as individual differences in sensitivity to visceral signals, the influence of expectation and emotion on symptom perception, and changes related to disease chronicity, such as conditioning and plasticity. The synthesis of these literatures suggests that the insular and anterior cingulate cortices, in addition to other brain regions previously implicated in the regulation of emotion, may be both responsive to asthma-related bodily changes and important in influencing the appearance and persistence of symptom expression in asthma.

Individuals with asthma have twice the risk of developing mood and anxiety disorders as individuals without asthma and these psychological factors are associated with worse outcomes and greater need for medical intervention. Similarly, asthma symptom onset and exacerbation often occur during times of increased psychological stress. Remission from depression, on the other hand, is associated with improvement in asthma symptoms and decreased usage of asthma medication. Yet research aimed at understanding the biological underpinnings of asthma has focused almost exclusively on the periphery. An extensive literature documents the relationship between emotion and asthma, but little work has explored the function of affective neural circuitry in asthma symptom expression. Therefore, the following review integrates neuroimaging research related to factors that may impact symptom expression in asthma, such as individual differences in sensitivity to visceral signals, the influence of expectation and emotion on symptom perception, and changes related to disease chronicity, such as conditioning and plasticity. The synthesis of these literatures suggests that the insular and anterior cingulate cortices, in addition to other brain regions previously implicated in the regulation of emotion, may be both responsive to asthma-related bodily changes and important in influencing the appearance and persistence of symptom expression in asthma.
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Twenty-six younger (ages 18–36 years) and 19 older (ages 60–88 years) healthy right-handed men and women were tested for interhemispheric transfer by using visual evoked potentials lo laterally presented checkerboards. Interhemispheric transfer time (IHTT) was estimated by subtracting latencies for both P100 and N160 peaks of the waveform contralateral to the stimulus from the waveform ipsilateral to the stimulus for homologous sites. The quality of interhemispheric transfer was estimated by comparing peak-to-peak amplitudes for homologous sites. IHTT did not change across age, but there was a suppression of the waveform over the indirectly stimulated hemisphere in the older participants. The significance of this finding for age-related changes in functions mediated by the corpus callosum is discussed.
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Despite growing evidence on the neural bases of emotion regulation, little is known about the mechanisms underlying individual differences in cognitive regulation of negative emotion, and few studies have used objective measures to quantify regulatory success. Using a trait-like psychophysiological measure of emotion regulation, corrugator electromyography, we obtained an objective index of the ability to cognitively reappraise negative emotion in 56 healthy men (Session 1), who returned 1.3 years later to perform the same regulation task using fMRI (Session 2). Results indicated that the corrugator measure of regulatory skill predicted amygdala-prefrontal functional connectivity. Individuals with greater ability to down-regulate negative emotion as indexed by corrugator at Session 1 showed not only greater amygdala attenuation but also greater inverse connectivity between the amygdala and several sectors of the prefrontal cortex while down-regulating negative emotion at Session 2. Our results demonstrate that individual differences in emotion regulation are stable over time and underscore the important role of amygdala-prefrontal coupling for successful regulation of negative emotion.
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Anxious temperament (AT) in human and non-human primates is a trait-like phenotype evident early in life that is characterized by increased behavioural and physiological reactivity to mildly threatening stimuli. Studies in children demonstrate that AT is an important risk factor for the later development of anxiety disorders, depression and comorbid substance abuse. Despite its importance as an early predictor of psychopathology, little is known about the factors that predispose vulnerable children to develop AT and the brain systems that underlie its expression. To characterize the neural circuitry associated with AT and the extent to which the function of this circuit is heritable, we studied a large sample of rhesus monkeys phenotyped for AT. Using 238 young monkeys from a multigenerational single-family pedigree, we simultaneously assessed brain metabolic activity and AT while monkeys were exposed to the relevant ethological condition that elicits the phenotype. High-resolution (18)F-labelled deoxyglucose positron-emission tomography (FDG-PET) was selected as the imaging modality because it provides semi-quantitative indices of absolute glucose metabolic rate, allows for simultaneous measurement of behaviour and brain activity, and has a time course suited for assessing temperament-associated sustained brain responses. Here we demonstrate that the central nucleus region of the amygdala and the anterior hippocampus are key components of the neural circuit predictive of AT. We also show significant heritability of the AT phenotype by using quantitative genetic analysis. Additionally, using voxelwise analyses, we reveal significant heritability of metabolic activity in AT-associated hippocampal regions. However, activity in the amygdala region predictive of AT is not significantly heritable. Furthermore, the heritabilities of the hippocampal and amygdala regions significantly differ from each other. Even though these structures are closely linked, the results suggest differential influences of genes and environment on how these brain regions mediate AT and the ongoing risk of developing anxiety and depression.
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BACKGROUND: Autism is a syndrome of unknown cause, marked by abnormal development of social behavior. Attempts to link pathological features of the amygdala, which plays a key role in emotional processing, to autism have shown little consensus. OBJECTIVE: To evaluate amygdala volume in individuals with autism spectrum disorders and its relationship to laboratory measures of social behavior to examine whether variations in amygdala structure relate to symptom severity. DESIGN: We conducted 2 cross-sectional studies of amygdala volume, measured blind to diagnosis on high-resolution, anatomical magnetic resonance images. Participants were 54 males aged 8 to 25 years, including 23 with autism and 5 with Asperger syndrome or pervasive developmental disorder not otherwise specified, recruited and evaluated at an academic center for developmental disabilities and 26 age- and sex-matched community volunteers. The Autism Diagnostic Interview-Revised was used to confirm diagnoses and to validate relationships with laboratory measures of social function. MAIN OUTCOME MEASURES: Amygdala volume, judgment of facial expressions, and eye tracking. RESULTS: In study 1, individuals with autism who had small amygdalae were slowest to distinguish emotional from neutral expressions (P=.02) and showed least fixation of eye regions (P=.04). These same individuals were most socially impaired in early childhood, as reported on the Autism Diagnostic Interview-Revised (P<.04). Study 2 showed smaller amygdalae in individuals with autism than in control subjects (P=.03) and group differences in the relation between amygdala volume and age. Study 2 also replicated findings of more gaze avoidance and childhood impairment in participants with autism with the smallest amygdalae. Across the combined sample, severity of social deficits interacted with age to predict different patterns of amygdala development in autism (P=.047). CONCLUSIONS: These findings best support a model of amygdala hyperactivity that could explain most volumetric findings in autism. Further psychophysiological and histopathological studies are indicated to confirm these findings.
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This study compared the asymmetry of different features of brain electrical activity during the performance of a verbal task (word finding) and a spatial task (dot localization) that had been carefully matched on psychometric properties and accompanying motor activity. Nineteen right-handed subjects were tested. EEG was recorded from F3, F4, C3, C4, P3, and P4, referred to both CZ and computer-derived averaged-ears references, and Fourier transformed. Power in the delta, theta, alpha, and beta bands was computed. There were significant Task X Hemisphere effects in all bands for CZ-referenced data and for the alpha and beta bands for ears-referenced data. The effects were always either greater power suppression in the hemisphere putatively most engaged in task processing or greater power in the opposite hemisphere. Correlations between EEG and task performance indicated that CZ-referenced parietal alpha asymmetry accounted for the most variance in verbal task performance. Power within individual hemispheres or across hemispheres was unrelated to task performance. The findings indicate robust differences in asymmetrical brain physiology that are produced by well-matched verbal and spatial cognitive tasks.
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Research on the neural substrates of emotion has found evidence for cortical asymmetries for aspects of emotion. A recent article by Nicholls et al. has used a new imaging method to interrogate facial movement in 3D to assess possible asymmetrical action during expressions of happiness and sadness. Greater left-sided movement, particularly during expressions of sadness was observed. These findings have implications for understanding hemispheric differences in emotion and lend support to the notion that aspects of emotion processing might be differentially localized in the two hemispheres.
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Assessed the cortical concomitants of selective mode-specific attention in Ss differing in the capacity for sustained attentional involvement. 10 high- and 10 low-scoring Ss on the Tellegen Absorption Scale were required to (a) simply attend to either a randomly flashing light or a randomly produced tapping sensation on the forearm during one block of trials and to (b) count the flashes and the taps during another trial block. The EEG was recorded from the left occipital and left sensorimotor regions and was filtered for alpha activity and quantified on line. Selective mode-specific attention produced reliable shifts in cortical patterning between kinesthetic and visual attention trials. During the counting condition, high-scoring Ss showed significantly greater specificity in cortical patterning than did low-scoring Ss. This difference was primarily a function of high-scoring Ss' ability to inhibit activation in the occipital region while counting taps. Findings suggest that high scores on the Absorption scale are associated with a flexible attentional style and that, given the requisite task demands, attentionally absorbed Ss show greater mode-specific cortical patterning during selective attention than do low scorers. (36 ref)
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We conducted assessments of 28 children with impaired vision (VI group), with ages ranging from 12 to 17 years, and an equal number of age-matched, normal-sighted children (NS group). The VI group had significantly higher rates of breathing, heart rates, and diastolic blood pressure values compared to the NS group (Mann–Whitney U test). Twenty-four of the VI group formed pairs matched for age and degree of blindness, and we randomly assigned members of the pairs to two groups, viz., yoga and physical activity. Both groups spent an hour each day practicing yoga or working in the garden, depending on their group. After 3 weeks, the yoga group showed a significant decrease in breath rate (Wilcoxon paired signed ranks test). There was no change after the physical activity program. The results showed that children with visual impairment have higher physiological arousal than children with normal sight, with a marginal reduction in arousal following yoga.

The authors examined the time course of affective responding associated with different affective dimensions--anxious apprehension, anxious arousal, and anhedonic depression--using an emotion-modulated startle paradigm. Participants high on 1 of these 3 dimensions and nonsymptomatic control participants viewed a series of affective pictures with acoustic startle probes presented before, during, and after the stimuli. All groups exhibited startle potentiation during unpleasant pictures and in anticipation of both pleasant and unpleasant pictures. Compared with control participants, symptomatic participants exhibited sustained potentiation following the offset of unpleasant stimuli and a lack of blink attenuation during and following pleasant stimuli. Common and unique patterns of affective responses in the 3 types of mood symptoms are discussed.
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In a recent neuroimaging study of macaque monkeys, Gil-da-Costa and colleagues reported that a distributed circuit of modality-specific properties represents macaques' conceptual knowledge of social situations. The circuit identified shows striking similarities to analogous circuits in humans that represent conceptual knowledge. This parallel suggests that a common architecture underlies the conceptual systems of different species, although with additional systems extending human conceptual abilities significantly.
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Early life stress (ELS) and function of the hypothalamic-pituitary-adrenal axis predict later psychopathology. Animal studies and cross-sectional human studies suggest that this process might operate through amygdala-ventromedial prefrontal cortex (vmPFC) circuitry implicated in the regulation of emotion. Here we prospectively investigated the roles of ELS and childhood basal cortisol amounts in the development of adolescent resting-state functional connectivity (rs-FC), assessed by functional connectivity magnetic resonance imaging (fcMRI), in the amygdala-PFC circuit. In females only, greater ELS predicted increased childhood cortisol levels, which predicted decreased amygdala-vmPFC rs-FC 14 years later. For females, adolescent amygdala-vmPFC functional connectivity was inversely correlated with concurrent anxiety symptoms but positively associated with depressive symptoms, suggesting differing pathways from childhood cortisol levels function through adolescent amygdala-vmPFC functional connectivity to anxiety and depression. These data highlight that, for females, the effects of ELS and early HPA-axis function may be detected much later in the intrinsic processing of emotion-related brain circuits.
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OBJECTIVE: This study was undertaken to identify brain structures associated with emotion in normal elderly subjects. METHOD: Eight normal subjects aged 55-78 years were shown film clips intended to provoke the emotions of happiness, fear, or disgust as well as a neutral state. During emotional activation, regional cerebral blood flow was measured with the use of [15O]H2O positron emission tomography imaging, and subjective emotional responses were recorded. Data were analyzed by subtracting the values during the neutral condition from the values in the various emotional activations. RESULTS: The stimuli produced a general activation in visual pathways that included the primary and secondary visual cortex, involving regions associated with object and spatial recognition. In addition, the specific emotions produced different regional limbic activations, which suggests that different pathways may be used for different types of emotional stimuli. CONCLUSIONS: Emotional activation in normal elderly subjects was associated with increases in blood flow in limbic and paralimbic brain structures. Brain activation may be specific to the emotion being elicited but probably involves complex sensory, association, and memory circuitry. Further studies are needed to identify activations that are specific for emotion.
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"Readers will learn new methods for teaching relaxation and quiet inner focus, movement meditations, and exercises that develop emotional, spiritual and intellectual awareness and self-esteem. These exercises aim to help students gain new-found creativity, a language to articulate their feelings, and skills for attaining a calm and balanced outlook."--BOOK JACKET.

People believe they see emotion written on the faces of other people. In an instant, simple facial actions are transformed into information about another's emotional state. The present research examined whether a perceiver unknowingly contributes to emotion perception with emotion word knowledge. We present 2 studies that together support a role for emotion concepts in the formation of visual percepts of emotion. As predicted, we found that perceptual priming of emotional faces (e.g., a scowling face) was disrupted when the accessibility of a relevant emotion word (e.g., anger) was temporarily reduced, demonstrating that the exact same face was encoded differently when a word was accessible versus when it was not. The implications of these findings for a linguistically relative view of emotion perception are discussed.
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This study examined the effects of meditation on mental imagery, evaluating Buddhist monks' reports concerning their extraordinary imagery skills. Practitioners of Buddhist meditation were divided into two groups according to their preferred meditation style: Deity Yoga (focused attention on an internal visual image) or Open Presence (evenly distributed attention, not directed to any particular object). Both groups of meditators completed computerized mental-imagery tasks before and after meditation. Their performance was compared with that of control groups, who either rested or performed other visuospatial tasks between testing sessions. The results indicate that all the groups performed at the same baseline level, but after meditation, Deity Yoga practitioners demonstrated a dramatic increase in performance on imagery tasks compared with the other groups. The results suggest that Deity meditation specifically trains one's capacity to access heightened visuospatial processing resources, rather than generally improving visuospatial imagery abilities.

In two prior studies, we investigated the neural mechanisms of spatial attention using a combined event-related potential (ERP) and positron emission tomography (PET) approach (Heinze et al. [1994]: Nature 392:543-546; Mangun et al. [1997]: Hum Brain Mapp 5:273-279). Neural activations in extrastriate cortex were observed in the PET measures for attended stimuli, and these effects were related to attentional modulations in the ERPs at specific latencies. The present study used functional magnetic resonance imaging (fMRI) and ERPs in single subjects to investigate the intersubject variability in extrastriate spatial attention effects, and to qualitatively compare this to variations in ERP attention effects. Activations in single subjects replicated our prior group-averaged PET findings, showing attention-related increases in blood flow in the posterior fusiform and middle occipital gyri in the hemisphere contralateral to attended visual stimuli. All subjects showed attentional modulations of the occipital P1 component of the ERPs. These findings in single subjects demonstrate the consistency of extrastriate attention effects, and provide information about the feasibility of this approach for integration of electrical and functional imaging data.
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BACKGROUND: Relationships between aberrant social functioning and depression have been explored via behavioral, clinical, and survey methodologies, highlighting their importance in the etiology of depression. The neural underpinnings of these relationships, however, have not been explored. METHODS: Nine depressed participants and 14 never-depressed control subjects viewed emotional and neutral pictures at two functional magnetic resonance imaging (fMRI) scanning sessions approximately 22 weeks apart. In the interim, depressed patients received the antidepressant Venlafaxine. Positively rated images were parsed into three separate comparisons: social interaction, human faces, and sexual images; across scanning session, activation to these images was compared with other positively rated images. RESULTS: For each of the three social stimulus types (social interaction, faces, sexual images), a distinguishable circuitry was activated equally in non-depressed control subjects and post-treatment depressed subjects but showed a hypo-response in the depressed group pre-treatment. These structures include regions of prefrontal, temporal, and parietal cortices, insula, basal ganglia, and the hippocampus. CONCLUSIONS: The neural hypo-response to positively valenced social stimuli that is observed in depression remits as response to antidepressant medication occurs, suggesting a state-dependent deficiency in response to positive social incentives. These findings underscore the importance of addressing social dysfunction in research and treatment of depression.
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Neuroanatomists posit that the central nucleus of the amygdala (Ce) and bed nucleus of the stria terminalis (BST) comprise two major nodes of a macrostructural forebrain entity termed the extended amygdala. The extended amygdala is thought to play a critical role in adaptive motivational behavior and is implicated in the pathophysiology of maladaptive fear and anxiety. Resting functional connectivity of the Ce was examined in 107 young anesthetized rhesus monkeys and 105 young humans using standard resting-state functional magnetic resonance imaging (fMRI) methods to assess temporal correlations across the brain. The data expand the neuroanatomical concept of the extended amygdala by finding, in both species, highly significant functional coupling between the Ce and the BST. These results support the use of in vivo functional imaging methods in nonhuman and human primates to probe the functional anatomy of major brain networks such as the extended amygdala.
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Examined whether children with dyslexia (DYS) differ from matched controls on visual evoked potential measures of interhemispheric transfer time (IHTT). 20 right-handed boys (aged 9–12 yrs), 10 with DYS and 10 with normal reading ability, were selected to participate based on a battery of neuropsychological and reading tests. Checkerboard flashes were presented to Ss hemiretinally while evoked responses were recorded from right and left side occipital scalp locations. IHTT was computed separately in response to right and left visual field presentations. Ss with DYS were found to have faster IHTT from right-to-left hemisphere and slower IHTT from left-to-right hemisphere compared with controls. Evoked potential measures of IHTT accounted for significant variance in measures of reading and related cognitive skills.
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Individuals differ dramatically in the quality and intensity of their response to affectively evocative stimuli. On the basis of prior theory and research, we hypothesized that these individual differences are related to variation in activation of the left and right frontal brain regions. We recorded baseline brain electrical activity from subjects on two occasions 3 weeks apart. Immediately following the second recording, subjects were exposed to brief positive and negative emotional film clips. For subjects whose frontal asymmetry was stable across the 3-week period, greater left frontal activation was associated with reports of more intense positive affect in response to the positive films, whereas greater right frontal activation was associated with more intense reports of negative affect in response to the negative film clips. The methodological and theoretical implications of these data are discussed.
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