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Baseline resting electroencephalogram (EEG) activity was recorded from 6 normothymic depressives and 8 controls using three different reference montages. Power in all frequency bands was extracted by Fourier transformation. Significant Group X Region X Hemisphere interactions were found consistently for alpha band power only. Previously depressed subjects had less left-sided anterior and less right-sided posterior activation (i.e., more alpha activity) than did never depressed subjects. Previously depressed subjects had no history of pharmacological treatment and did not differ from controls in emotional state at the time of testing. The pattern of anterior and posterior asymmetry in the previously depressed subjects is similar to that found in acutely depressed subjects and suggests that this may be a state-independent marker for depression.
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Although once considered disruptive, self-conscious emotions are now theorized to be fundamentally involved in the regulation of social behavior. The present study examined the social regulation function of self-conscious emotions by comparing healthy participants with a neuropsychological population--patients with orbitofrontal lesions--characterized by selective regulatory deficits. Orbitofrontal patients and healthy controls participated in a series of tasks designed to assess their social regulation and self-conscious emotions. Another task assessed the ability to infer others' emotional states, an appraisal process involved in self-conscious emotion. Consistent with the theory that self-conscious emotions are important for regulating social behavior, the findings show that deficient behavioral regulation is associated with inappropriate self-conscious emotions that reinforce maladaptive behavior. Additionally, deficient behavioral regulation is associated with impairments in interpreting the self-conscious emotions of others.
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Electroencephalogram (EEG) alpha power has been demonstrated to be inversely related to mental activity and has subsequently been used as an indirect measure of brain activation. The thalamus has been proposed as an important site for modulation of rhythmic alpha activity. Studies in animals have suggested that cortical alpha rhythms are correlated with alpha rhythms in the thalamus. However, little empirical evidence exists for this relation in humans. In the current study, resting EEG and a fluorodeoxyglucose positron emission tomography scan were measured during the same experimental session. Over a 30-min period, average EEG alpha power across 28 electrodes from 27 participants was robustly inversely correlated with glucose metabolic activity in the thalamus. These data provide the first evidence for a relation between alpha EEG power and thalamic activity in humans.
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OBJECTIVE Deficits in positive affect and their neural bases have been associated with major depression. However, whether reductions in positive affect result solely from an overall reduction in nucleus accumbens activity and fronto-striatal connectivity or the additional inability to sustain engagement of this network over time is unknown. The authors sought to determine whether treatment-induced changes in the ability to sustain nucleus accumbens activity and fronto-striatal connectivity during the regulation of positive affect are associated with gains in positive affect. METHOD Using fMRI, the authors assessed the ability to sustain activity in reward-related networks when attempting to increase positive emotion during performance of an emotion regulation paradigm in 21 depressed patients before and after 2 months of antidepressant treatment. Over the same interval, 14 healthy comparison subjects underwent scanning as well. RESULTS After 2 months of treatment, self-reported positive affect increased. The patients who demonstrated the largest increases in sustained nucleus accumbens activity over the 2 months were those who demonstrated the largest increases in positive affect. In addition, the patients who demonstrated the largest increases in sustained fronto-striatal connectivity were also those who demonstrated the largest increases in positive affect when controlling for negative affect. None of these associations were observed in healthy comparison subjects. CONCLUSIONS Treatment-induced change in the sustained engagement of fronto-striatal circuitry tracks the experience of positive emotion in daily life. Studies examining reduced positive affect in a variety of psychiatric disorders might benefit from examining the temporal dynamics of brain activity when attempting to understand changes in daily positive affect.
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<p>OBJECTIVES: The study objectives were to develop and objectively assess the therapeutic effect of a novel movement-based complementary and alternative medicine approach for children with an autism-spectrum disorder (ASD). DESIGN: A within-subject analysis comparing pre- to post-treatment scores on two standard measures of childhood behavioral problems was used. SETTINGS AND LOCATION: The intervention and data analysis occurred at a tertiary care, medical school teaching hospital. SUBJECTS: Twenty-four (24) children aged 3-16 years with a diagnosis of an ASD comprised the study group. INTERVENTION: The efficacy of an 8-week multimodal yoga, dance, and music therapy program based on the relaxation response (RR) was developed and examined. OUTCOME MEASURES: The study outcome was measured using The Behavioral Assessment System for Children, Second Edition (BASC-2) and the Aberrant Behavioral Checklist (ABC). RESULTS: Robust changes were found on the BASC-2, primarily for 5-12-year-old children. Unexpectedly, the post-treatment scores on the Atypicality scale of the BASC-2, which measures some of the core features of autism, changed significantly (p=0.003). CONCLUSIONS: A movement-based, modified RR program, involving yoga and dance, showed efficacy in treating behavioral and some core features of autism, particularly for latency-age children.</p>
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Given the central role of the amygdala in fear perception and expression and its likely abnormality in affective disorders and autism, there is great demand for a technique to measure differences in neurochemistry of the human amygdala. Unfortunately, it is also a technically complex target for magnetic resonance spectroscopy (MRS) due to a small volume, high field inhomogeneity and a shared boundary with hippocampus, which can undergo opposite changes in response to stress. We attempted to achieve reliable PRESS-localized single-voxel MRS at 3T of the isolated human amygdala by using anatomy to guide voxel size and location. We present data from 106 amygdala-MRS sessions from 58 volunteers aged 10 to 52 years, including two tests of one-week stability and a feasibility study in an adolescent sample. Our main outcomes were indices of spectral quality, repeated measurement variability (within- and between-subject standard deviations), and sensitivity to stable individual differences measured by intra-class correlation (ICC). We present metrics of amygdala-MRS reliability for n-acetyl-aspartate, creatine, choline, myo-Inositol, and glutamate+glutamine (Glx). We found that scan quality suffers an age-related difference in field homogeneity and modified our protocol to compensate. We further identified an effect of anatomical inclusion near the endorhinal sulcus, a region of high synaptic density, that contributes up to 29% of within-subject variability across 4 sessions (n=14). Remaining variability in line width but not signal-to-noise also detracts from reliability. Statistical correction for partial inclusion of these strong neurochemical gradients decreases n-acetyl-aspartate reliability from an intraclass correlation of 0.84 to 0.56 for 7-minute acquisitions. This suggests that systematic differences in anatomical inclusion can contribute greatly to apparent neurochemical concentrations and could produce false group differences in experimental studies. Precise, anatomically-based prescriptions that avoid age-related sources of inhomogeneity and use longer scan times may permit study of individual differences in neurochemistry throughout development in this late-maturing structure.
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Depression has been associated with dysfunctional executive functions and abnormal activity within the anterior cingulate cortex (ACC), a region critically involved in action regulation. Prior research invites the possibility that executive deficits in depression may arise from abnormal responses to negative feedback or errors, but the underlying neural substrates remain unknown. We hypothesized that abnormal reactions to error would be associated with dysfunctional rostral ACC activity, a region previously implicated in error detection and evaluation of the emotional significance of events. To test this hypothesis, subjects with low and high Beck Depression Inventory (BDI) scores performed an Eriksen Flanker task. To assess whether tonic activity within the rostral ACC predicted post-error adjustments, 128-channel resting EEG data were collected before the task and analyzed with low-resolution electromagnetic tomography (LORETA) using a region-of-interest approach. High BDI subjects were uniquely characterized by significantly lower accuracy after incorrect than correct trials. Mirroring the behavioral findings, high BDI subjects had significantly reduced pretask gamma (36.5-44 Hz) current density within the affective (rostral; BA24, BA25, BA32) but not cognitive (dorsal; BA24', BA32') ACC subdivision. For low, but not high, BDI subjects pretask gamma within the affective ACC subdivision predicted post-error adjustments even after controlling for activity within the cognitive ACC subdivision. Abnormal responses to errors may thus arise due to lower activity within regions subserving affective and/or motivational responses to salient cues. Because rostral ACC regions have been implicated in treatment response in depression, our findings provide initial insight into putative mechanisms fostering treatment response.
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Several different models postulate that depression is associated with decreased approach-related behavior. Relatively little has been done to date to specifically investigate this issue. In the present study, a signal-detection analysis was used to examine the response biases of dysphoric and nondysphoric female undergraduates during 3 payoff conditions: neutral, reward, and punishment. As predicted, the dysphoric subjects had a smaller change in bias from the neutral to the reward condition compared with the nondysphoric group. The 2 groups did not differ during the neutral and punishment conditions. These findings are consistent with the hypothesis that the left frontal hypoactivation observed in depression reflects a deficit in approach-related behavior.
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Although several studies have examined anterior asymmetric brain electrical activity and cortisol in infants, children, and adults, the direct association between asymmetry and cortisol has not systematically been reported. In nonhuman primates, greater relative right anterior activation has been associated with higher cortisol levels. The current study examines the relation between frontal electroencephalographic (EEG) asymmetry and cortisol (basal and reactive) and withdrawal-related behaviors (fear and sadness) in 6-month-old infants. As predicted, the authors found that higher basal and reactive cortisol levels were associated with extreme right EEG asymmetry. EEG during the withdrawal-negative affect task was associated with fear and sadness behaviors. Results are interpreted in the context of the previous primate work, and some putative mechanisms are discussed.
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<p>Subregional analyses of the hippocampus have suggested a selective role for the CA1 subregion in intermediate/long-term spatial memory and consolidation, but not short-term acquisition or encoding processes. It remains unclear how the direct cortical projection to CA1 via the perforant path (pp) contributes to these CA1-dependent processes. It has been suggested that dopamine selectively modulates the pp projection to CA1 while having little to no effect on the Schaffer collateral (SC) projection to CA1. This series of behavioral and electrophysiological experiments takes advantage of this pharmacological dissociation to demonstrate that the direct pp inputs to CA1 are critical in CA1-dependent intermediate-term retention and retrieval function. Here we demonstrate that local infusion of the nonselective dopamine agonist, apomorphine (10, 15 microg), into the CA1 subregion of awake animals produces impairments in between-day retention and retrieval, sparing within-day encoding of a modified Hebb-Williams maze and contextual conditioning of fear. In contrast, apomorphine produces no deficits when infused into the CA3 subregion. To complement the behavioral analyses, electrophysiological data was collected. In anesthetized animals, local infusion of the same doses of apomorphine significantly modifies evoked responses in the distal dendrites of CA1 following angular bundle stimulation, but produces no significant effects in the more proximal dendritic layer following stimulation of the SC. These results support a modulatory role for dopamine in the EC-CA1, but not CA3-CA1 circuitry, and suggest the possibility of a more fundamental role for EC-CA1 synaptic transmission in terms of intermediate-term, but not short-term spatial memory.</p>
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BACKGROUND: Excessive behavioral inhibition during childhood marks anxious temperament and is a risk factor for the development of anxiety and affective disorders. Studies in nonhuman primates can provide important information related to the expression of this risk factor, since threat-induced freezing in rhesus monkeys is a trait-like characteristic analogous to human behavioral inhibition. The orbitofrontal cortex (OFC) and amygdala are part of a circuit involved in the processing of emotions and associated physiological responses. Earlier work demonstrated involvement of the primate central nucleus of the amygdala (CeA) in mediating anxious temperament. This study assessed the role of the primate OFC in mediating anxious temperament and its involvement in fear responses. METHODS: Twelve adolescent rhesus monkeys were studied (six lesion and six control monkeys). Lesions were targeted at regions of the OFC that are most interconnected with the amygdala. Behavior and physiological parameters were assessed before and after the lesions. RESULTS: The OFC lesions significantly decreased threat-induced freezing and marginally decreased fearful responses to a snake. The lesions also resulted in a leftward shift in frontal brain electrical activity consistent with a reduction in anxiety. The lesions did not significantly decrease hypothalamic-pituitary-adrenal (HPA) activity or cerebrospinal fluid (CSF) concentrations of corticotrophin-releasing factor (CRF). CONCLUSIONS: These findings demonstrate a role for the OFC in mediating anxious temperament and fear-related responses in adolescent primates. Because of the similarities between rhesus monkey threat-induced freezing and childhood behavioral inhibition, these findings are relevant to understanding mechanisms underlying anxious temperament in humans.
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Drawing on recent claims in the study of relationships, attachment, and emotion, the authors hypothesized that romantic love serves a commitment-related function and sexual desire a reproduction-related function. Consistent with these claims, in Study 1, brief experiences of romantic love and sexual desire observed in a 3-min interaction between romantic partners were related to distinct feeling states, distinct nonverbal displays, and commitment- and reproductive-related relationship outcomes, respectively. In Study 2, the nonverbal display of romantic love was related to the release of oxytocin. Discussion focuses on the place of romantic love and sexual desire in the literature on emotion.
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This study, based on a sample of 172 children, examined the relation between average afternoon salivary cortisol levels measured at home at age 4.5 years and socioemotional adjustment a year and a half later, as reported by mothers, fathers, and teachers. Cortisol levels were hypothesized to be positively associated with withdrawal-type behaviors (e.g., internalizing, social wariness) and inversely related to approach-type behaviors, both negative and positive (e.g., externalizing, school engagement). Higher cortisol levels at age 4.5 predicted more internalizing behavior and social wariness as reported by teachers and mothers, although child gender moderated the relation between cortisol and mother report measures. An inverse relation was found between boys' cortisol levels and father report of externalizing behavior. A marginal inverse relation was found between child cortisol levels and teacher report of school engagement. Behavior assessed concurrently with cortisol collection did not account for the prospective relations observed,suggesting that cortisol adds uniquely to an understanding of behavioral development.
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Schools are searching for innovative ways to meet the unique academic, social-emotional, and behavioral needs of adolescents, many of whom face serious personal and family challenges. An innovative practice that is currently being introduced into school settings is meditation. Types of meditation offered in school-based settings include mindfulness meditation, the relaxation response, and Transcendental Meditation. These practices, as cognitive-behavioral interventions that are available for use by social workers and other school professionals, help students to enhance academic and psychosocial strengths and improve self-regulation capacities and coping abilities. This article defines meditation and meditative practices, reviews the literature showing the benefits and challenges of offering meditation to adolescents in a school-based setting, and describes the relevance of these practices for adolescents. The article also discusses implications for school social workers, teachers, and school administrators and reflects on the current research and future efforts toward building the research base for the promising practice of meditation in schools.
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Our objective was to conduct the first randomized controlled trial of the efficacy of a group mindfulness program aimed at reducing and preventing depression in an adolescent school-based population. For each of 12 pairs of parallel classes with students (age range 13–20) from five schools (N = 408), one class was randomly assigned to the mindfulness condition and one class to the control condition. Students in the mindfulness group completed depression assessments (the Depression Anxiety Stress Scales) prior to and immediately following the intervention and 6 months after the intervention. Control students completed the questionnaire at the same times as those in the mindfulness group. Hierarchical linear modeling showed that the mindfulness intervention showed significantly greater reductions (and greater clinically significant change) in depression compared with the control group at the 6-month follow-up. Cohen's d was medium sized (>.30) for both the pre-to-post and pre-to-follow-up effect for depressive symptoms in the mindfulness condition. The findings suggest that school-based mindfulness programs can help to reduce and prevent depression in adolescents.
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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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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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This paper reports three studies showing sex differences in EEG asymmetry during self-generated cognitive and affective tasks. In the first experiment, bilateral EEG, quantified for alpha on-line, was recorded from right-handed subjects while they either whistled, sang or recited lyrics of familiar songs. The results revealed significant asymmetry between the whistle and talk conditions only for subjects with no familial left-handedness and, within this group, only for females and not for males. In the second experiment, bilateral EEG was recorded while right-handed subjects (with no familial left-handedness) self-induced covert affective and non-affective states. Results revealed significantly greater relative right-hemisphere activation during emotion versus non-emotion trials only in females; males showed no significant task-dependent shifts in asymmetry between conditions. The third experiment was designed to test the hypothesis that females show greater percent time asymmetry than males during biofeedback training for symmetrical and asymmetrical EEG patterns. Results confirmed this prediction as well as indicating that females show better control of such asymmetrical cortical patterning. These findings provide new neuropsychological support for the hypothesis of greater bilateral flexibility in females during self-generation tasks.
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<p>Background : Recent research suggests that the Mindfulness-Based Stress Reduction program has positive effects on health, but little is known about the immediate physiological effects of different components of the program. Purpose : To examine the short-term autonomic and cardiovascular effects of one of the techniques employed in mindfulness meditation training, a basic body scan meditation. Methods : In Study 1, 32 healthy young adults (23 women, 9 men) were assigned randomly to either a meditation, progressive muscular relaxation or wait-list control group. Each participated in two laboratory sessions 4 weeks apart in which they practiced their assigned technique. In Study 2, using a within-subjects design, 30 healthy young adults (15 women, 15 men) participated in two laboratory sessions in which they practiced meditation or listened to an audiotape of a popular novel in counterbalanced order. Heart rate, cardiac respiratory sinus arrhythmia (RSA), and blood pressure were measured in both studies. Additional measures derived from impedance cardiography were obtained in Study 2. Results : In both studies, participants displayed significantly greater increases in RSA while meditating than while engaging in other relaxing activities. A significant decrease in cardiac pre-ejection period was observed while participants meditated in Study 2. This suggests that simultaneous increases in cardiac parasympathetic and sympathetic activity may explain the lack of an effect on heart rate. Female participants in Study 2 exhibited a significantly larger decrease in diastolic blood pressure during meditation than the novel, whereas men had greater increases in cardiac output during meditation compared to the novel. Conclusions : The results indicate both similarities and differences in the physiological responses to body scan meditation and other relaxing activities.</p>

<p>For decades the importance of background situations has been documented across all areas of cognition. Nevertheless, theories of concepts generally ignore background situations, focusing largely on bottom-up, stimulus-based processing. Furthermore, empirical research on concepts typically ignores background situations, not incorporating them into experimental designs. A selective review of relevant literatures demonstrates that concepts are not abstracted out of situations but instead are situated. Background situations constrain conceptual processing in many tasks (e.g., recall, recognition, categorization, lexical decision, color naming, property verification, property generation) across many areas of cognition (e.g., episodic memory, conceptual processing, visual object recognition, language comprehension). A taxonomy of situations is proposed in which grain size, meaningfulness, and tangibility distinguish the cumulative situations that structure cognition hierarchically.</p>
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Social class is shaped by an individual's material resources as well as perceptions of rank vis-à-vis others in society, and in this article, we examine how class influences behavior. Diminished resources and lower rank create contexts that constrain social outcomes for lower-class individuals and enhance contextualist tendencies--that is, a focus on external, uncontrollable social forces and other individuals who influence one's life outcomes. In contrast, abundant resources and elevated rank create contexts that enhance the personal freedoms of upper-class individuals and give rise to solipsistic social cognitive tendencies--that is, an individualistic focus on one's own internal states, goals, motivations, and emotions. Guided by this framework, we detail 9 hypotheses and relevant empirical evidence concerning how class-based contextualist and solipsistic tendencies shape the self, perceptions of the social environment, and relationships to other individuals. Novel predictions and implications for research in other socio-political contexts are considered.
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The phenomenon of empathy entails the ability to share the affective experiences of others. In recent years social neuroscience made considerable progress in revealing the mechanisms that enable a person to feel what another is feeling. The present review provides an in-depth and critical discussion of these findings. Consistent evidence shows that sharing the emotions of others is associated with activation in neural structures that are also active during the first-hand experience of that emotion. Part of the neural activation shared between self- and other-related experiences seems to be rather automatically activated. However, recent studies also show that empathy is a highly flexible phenomenon, and that vicarious responses are malleable with respect to a number of factors—such as contextual appraisal, the interpersonal relationship between empathizer and other, or the perspective adopted during observation of the other. Future investigations are needed to provide more detailed insights into these factors and their neural underpinnings. Questions such as whether individual differences in empathy can be explained by stable personality traits, whether we can train ourselves to be more empathic, and how empathy relates to prosocial behavior are of utmost relevance for both science and society.
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Power increases the tendency to behave in a goal-congruent fashion. Guided by this theoretical notion, we hypothesized that elevated power would strengthen the positive association between prosocial orientation and empathic accuracy. In 3 studies with university and adult samples, prosocial orientation was more strongly associated with empathic accuracy when distinct forms of power were high than when power was low. In Study 1, a physiological indicator of prosocial orientation, respiratory sinus arrhythmia, exhibited a stronger positive association with empathic accuracy in a face-to-face interaction among dispositionally high-power individuals. In Study 2, experimentally induced prosocial orientation increased the ability to accurately judge the emotions of a stranger but only for individuals induced to feel powerful. In Study 3, a trait measure of prosocial orientation was more strongly related to scores on a standard test of empathic accuracy among employees who occupied high-power positions within an organization. Study 3 further showed a mediated relationship between prosocial orientation and career satisfaction through empathic accuracy among employees in high-power positions but not among employees in lower power positions. Discussion concentrates upon the implications of these findings for studies of prosociality, power, and social behavior.
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OBJECTIVE: To test the hypothesis that socioeconomic status (SES) would be associated with sleep quality measured objectively, even after controlling for related covariates (health status, psychosocial characteristics). Epidemiological studies linking SES and sleep quality have traditionally relied on self-reported assessments of sleep. METHODS: Ninety-four women, 61 to 90 years of age, participated in this study. SES was determined by pretax household income and years of education. Objective and subjective assessments of sleep quality were obtained using the NightCap sleep system and the Pittsburgh Sleep Quality Index (PSQI), respectively. Health status was determined by subjective health ratings and objective measures of recent and chronic illnesses. Depressive symptoms and neuroticism were quantified using the Center for Epidemiological Studies Depression Scale and the Neuroticism subscale of the NEO Personality Inventory, respectively. RESULTS: Household income significantly predicted sleep latency and sleep efficiency even after adjusting for demographic factors, health status, and psychosocial characteristics. Income also predicted PSQI scores, although this association was significantly attenuated by inclusion of neuroticism in multivariate analyses. Education predicted both sleep latency and sleep efficiency, but the latter association was partially reduced after health status and psychosocial measures were included in analyses. Education predicted PSQI sleep efficiency component scores, but not global scores. CONCLUSIONS: These results suggest that SES is robustly linked to both subjective and objective sleep quality, and that health status and psychosocial characteristics partially explain these associations.
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