Lei Sheu

University of Pittsburgh | Pitt · Psychology

Limbic white matter pathways link emotion, cognition, and behavior and are potentially malleable to the influences of traumatic events throughout development. However, the impact of interactions between childhood and later life trauma on limbic white matter pathways has yet to be examined. Here, we examined whether childhood maltreatment moderated...

Hypertension is a presumptive risk factor for premature cognitive decline. However, lowering blood pressure (BP) does not uniformly reverse cognitive decline, suggesting that high BP per se may not cause cognitive decline. We hypothesized that essential hypertension has initial effects on the brain that, over time, manifest as cognitive dysfunction...

Background Individuals who exhibit large‐magnitude blood pressure (BP) reactions to acute psychological stressors are at risk for hypertension and premature death by cardiovascular disease. This study tested whether a multivariate pattern of stressor‐evoked brain activity could reliably predict individual differences in BP reactivity, providing nov...

Table S1. The Training Sample (N=206) vs the Test (Cross‐Validation) Sample (N=104) Table S2. Stressor‐Evoked Brain Activation Revealed at a Family‐Wise Error Rate Corrected Threshold of P<0.05 Table S3. Regions Within the Whole‐Brain Multivariate Weight Map That Positively Predicted Stressor‐Evoked SBP Reactivity After Applying a Permutation Thr...

Late-life Generalized Anxiety Disorder (GAD) is relatively understudied and the underlying structural and functional neuroanatomy has received little attention. In this study, we compare the brain structural characteristics in white and gray matter in 31 non-anxious older adults and 28 late-life GAD participants. Gray matter indices (cortical thick...

Table S1. Neuropsychological Measures Listed Within the Derived Factor Used in Analyses

Background High blood pressure is thought to contribute to dementia in late life, but our understanding of the relationship between individual differences in blood pressure (BP) and cognitive functioning is incomplete. In this study, cognitive performance in nonhypertensive midlife adults was examined as a function of resting BP and regional cerebr...

The default mode network (DMN) encompasses brain systems that exhibit coherent neural activity at rest. DMN brain systems have been implicated in diverse social, cognitive, and affective processes, as well as risk for forms of dementia and psychiatric disorders that associate with systemic inflammation. Areas of the anterior cingulate cortex (ACC)...

Resting high-frequency heart rate variability (HF-HRV) relates to cardiac vagal control and predicts individual differences in health and longevity, but its functional neural correlates are not well defined. The medial prefrontal cortex (mPFC) encompasses visceral control regions that are components of intrinsic networks of the brain, particularly...

Residing in communities of socioeconomic disadvantage confers risk for chronic diseases and cognitive aging, as well as risk for biological factors that negatively affect brain morphology. The present study tested whether community disadvantage negatively associates with brain morphology via 2 biological factors encompassing cardiometabolic disease...

Anxiety is an all-inclusive concept incorporating somatic symptoms (palpitations, dizziness, dyspnea), emotional and cognitive elements (negative affect, fear, worry, rumination) and behavioral components (e.g., avoidance). The aim of this study was to examine the specific neural correlates associated with anxiety phenotypes (worry, rumination, som...

The biomarker model of Alzheimer's disease postulates a dynamic sequence of amyloidosis, neurodegeneration, and cognitive decline as an individual progresses from preclinical Alzheimer's disease to dementia. Despite supportive evidence from cross-sectional studies, verification with long-term within-individual data is needed. For this prospective c...

Inflammation is linked to cognitive decline in midlife, but the neural basis for this link is unclear. One possibility is that inflammation associates with adverse changes in brain morphology, which accelerates cognitive aging and later dementia risk. Clear evidence is lacking, however, regarding whether inflammation relates to cognition in midlife...

Diverse aspects of physical, affective, and cognitive health relate to social integration, reflecting engagement in social activities and identification with diverse roles within a social network. However, the mechanisms by which social integration interacts with the brain are unclear. In healthy adults (N=155) we tested the links between social in...

Objective: To evaluate alterations in cerebral blood flow (CBF) using arterial spin-labeled MRI in autosomal dominant Alzheimer disease (ADAD) mutation carriers (MCs) in relation to cerebral amyloid and compared with age-matched healthy controls. Background: Recent work has identified alterations in CBF in elderly subjects with mild cognitive im...

Generalized anxiety disorder (GAD) is one of the most prevalent anxiety disorders, but its neural basis is relatively understudied. This study aims to characterize the functional connectivity in the default mode network (DMN) in GAD across the lifespan. Functional and structural magnetic resonance imaging data were collected with subjects at rest....

Background and Aims Habitual physical activity is understood to help prevent type 2 diabetes and atherosclerotic cardiovascular disease via beneficial effects on both metabolism and the vascular system. However, individuals do not have uniform cardiometabolic responses to physical activity. Here we explore the extent to which variation in the proli...

Objectives Generalized Anxiety Disorder (GAD) is one of the most prevalent mental disorders in the elderly, but its functional neuroanatomy is not well understood. Given the role of emotion dysregulation in GAD, we sought to describe the neural bases of emotion regulation in late-life GAD by analyzing the functional connectivity (FC) in the Salienc...

Early life experience differentially shapes later stress reactivity, as evidenced by both animal and human studies. However, early experience-related changes in the function of central visceral neural circuits that control stress responses have not been well characterized, particularly in humans. The paraventricular nucleus of the hypothalamus (PVN...

Insulin resistance confers risk for diabetes mellitus and associates with a reduced capacity of the arterial baroreflex to regulate blood pressure. Importantly, several brain regions that comprise the central autonomic network, which controls the baroreflex, are also sensitive to the neuromodulatory effects of insulin. However, it is unknown whethe...

Cognitive reappraisal is a form of emotion regulation that alters emotional responding by changing the meaning of emotional stimuli. Reappraisal engages regions of the prefrontal cortex that support multiple functions, including visceral control functions implicated in regulating the immune system. Immune activity plays a role in the preclinical pa...

Being overweight or obese is associated with reduced white matter integrity throughout the brain. It is not yet clear which physiological systems mediate the association between inter-individual variation in adiposity and white matter. We tested whether composite indicators of cardiovascular, lipid, glucose, and inflammatory factors would mediate t...

White matter hyperintensities (WMHs) are often identified on T2-weighted magnetic resonance (MR) images in the elderly. The WMHs are generally associated with small vessel ischemic or pre-ischemic changes. However, the association of WMHs with blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) signal is understudied. I...

Socioeconomic disadvantage confers risk for aspects of ill health that may be mediated by systemic inflammatory influences on the integrity of distributed brain networks. Following this hypothesis, we tested whether socioeconomic disadvantage related to the structural integrity of white matter tracts connecting brain regions of distributed networks...

The arterial baroreflex is a key mechanism for the homeostatic control of blood pressure (BP). In animals and humans, psychological stressors suppress the capacity of the arterial baroreflex to control short-term fluctuations in BP, reflected by reduced baroreflex sensitivity (BRS). While animal studies have characterized the brain systems that lin...

We examined the reliability of measures of fMRI, subjective, and cardiovascular reactions to standardized versions of a Stroop color-word task and a multisource interference task. A sample of 14 men and 12 women (30-49 years old) completed the tasks on two occasions, separated by a median of 88 days. The reliability of fMRI BOLD signal changes in b...

Insulin resistance (IR) confers risk for Type 2 diabetes and is associated with depressed mood. Neurons within the ventral striatum (VS) are sensitive to insulin levels and show altered function in the context of both IR and depression. Hence, VS may represent a critical component of a neural circuitry linking IR to depressed mood. Ninety adults (a...

Socioeconomic disadvantage experienced in early development predicts ill health in adulthood. However, the neurobiological pathways linking early disadvantage to adult health remain unclear. Lower parental education-a presumptive indicator of early socioeconomic disadvantage-predicts health-impairing adult behaviors, including tobacco and alcohol d...

Exaggerated cardiovascular reactivity to stress is a risk factor for cardiovascular disease. Further, individual differences in stressor-evoked cardiovascular reactivity covary with the functionality of corticolimbic brain systems, particularly areas of the cingulate cortex. What remains unclear, however, is how individual differences in personalit...

Existing evidence links greater dietary intake of fish and (n-3) PUFA to better early brain development and lowered risk of cognitive disorders in late life. The mechanisms for these associations remain unclear and may be related to specific (n-3) fatty acids and may concern cognitive function generally rather than only early brain development and...

An individual's tendency to show exaggerated or otherwise dysregulated cardiovascular reactions to acute stressors has long been associated with increased risk for clinical and preclinical endpoints of coronary heart disease (CHD). However, the ‘brain-body’ pathways that link stressor-evoked cardiovascular reactions to CHD risk remain uncertain. Th...

To test whether current gray matter volume (GMV) covaried with previously obtained longitudinal measures of weight gain-as assessed by increases in body mass index (BMI)-among otherwise healthy postmenopausal women. Cross-sectional results indicate that reduced GMV may be associated with excess body weight. Demographic, biometric, and behavioral me...

Individuals who express relatively large-magnitude or "exaggerated" blood pressure (BP) reactions to behavioral stressors are presumably at increased risk for cardiovascular disease. As shown by recent neuroimaging studies, individuals who express exaggerated stressor-evoked BP reactivity also express heightened neural activity in corticolimbic bra...

Cardiovascular disease (CVD) is a major source of medical comorbidity for patients with mood and anxiety disorders, and it remains the leading public health burden for the general population in industrialized nations. Indirect neurobiological evidence suggests that preclinical risk for atherosclerosis, the main contributor to CVD, may be conferred...

The polyvagal theory states that social behavior is linked to cardiac vagal control. This theory has been tested widely in infants and children, but less so in adults. Thus, we examined if resting or stress-related changes in high-frequency heart rate variability (HF-HRV; a presumed index of vagal control) varied with social functioning in 50 healt...

Socioeconomic disadvantage during childhood and adolescence predicts poor mental and physical health and premature death by major medical diseases in adulthood. However, the neural pathways through which socioeconomic factors may exert a developmental influence on health and longevity remain largely unknown. This fMRI study provides novel evidence...

Individuals who exhibit exaggerated blood pressure reactions to psychological stressors are at risk for hypertension, ventricular hypertrophy, and premature atherosclerosis; however, the neural systems mediating exaggerated blood pressure reactivity and associated cardiovascular risk in humans remain poorly defined. Animal models indicate that the...

Chronic stress in non-human animals decreases the volume of the hippocampus, a brain region that supports learning and memory and that regulates neuroendocrine activity. In humans with stress-related psychiatric syndromes characterized by impaired learning and memory and dysregulated neuroendocrine activity, surrogate and retrospective indicators o...

Individuals who show exaggerated blood pressure reactions to psychological stressors are at increased risk for hypertension, atherosclerosis, and stroke. We tested whether individuals who show exaggerated stressor-induced blood pressure reactivity also show heightened stressor-induced neural activation in brain areas involved in controlling the car...

A nonlinear optimization problem is formulated to determine the optimal spacing between wind turbines to maximize instantaneous power from a one-line array of machines to be placed in a line parallel to constant wind direction. A specific example is then taken to illustrate the difference between optimal spacing and equidistant spacing.

Using five types of large scale weather systems (synoptic weather categories) and using average wind speed data over 15 minute intervals from Windsor, Massachusetts, time series models for average wind speed are developed. Using the Box-Jenkins approach it is shown that two basic types of time series models can be used to describe the time series o...