Ruth M. Benca

Bio: Ruth M. Benca is an academic researcher from University of California, Irvine. The author has contributed to research in topics: Non-rapid eye movement sleep & Polysomnography. The author has an hindex of 50, co-authored 162 publications receiving 10955 citations. Previous affiliations of Ruth M. Benca include Wake Forest University & University of Wisconsin-Madison.

Sleep and Psychiatric Disorders: A Meta-analysis

Abstract: We reviewed the literature on sleep in psychiatric disorders and evaluated the data by meta-analysis, a statistical method designed to combine data from different studies. A total of 177 studies with data from 7151 patients and controls were reviewed. Most psychiatric groups showed significantly reduced sleep efficiency and total sleep time, accounted for by decrements in non-rapid eye movement sleep. Rapid eye movement sleep time was relatively preserved in all groups, and percentage of rapid eye movement sleep was increased in affective disorders. Reduction in rapid eye movement sleep latency was seen in affective disorders but occurred in other categories as well. Although no single sleep variable appeared to have absolute specificity for any particular psychiatric disorder, patterns of sleep disturbances associated with categories of psychiatric illnesses were observed. Overall, findings for patients with affective disorders differed most frequently and significantly from those for normal controls.

Ten Putative Contributors to the Obesity Epidemic

Abstract: The obesity epidemic is a global issue and shows no signs of abating, while the cause of this epidemic remains unclear. Marketing practices of energy-dense foods and institutionally-driven declines...

Putative contributors to the secular increase in obesity: exploring the roads less traveled

Abstract: Putative contributors to the secular increase in obesity: exploring the roads less traveled

Anterior cingulate activity as a predictor of degree of treatment response in major depression: evidence from brain electrical tomography analysis.

Abstract: Objective: The anterior cingulate cortex has been implicated in depression. Results are best interpreted by considering anatomic and cytoarchitectonic subdivisions. Evidence suggests depression is characterized by hypoactivity in the dorsal anterior cingulate, whereas hyperactivity in the rostral anterior cingulate is associated with good response to treatment. The authors tested the hypothesis that activity in the rostral anterior cingulate during the depressed state has prognostic value for the degree of eventual response to treatment. Whereas prior studies used hemodynamic imaging, this investigation used EEG. Method: The authors recorded 28-channel EEG data for 18 unmedicated patients with major depression and 18 matched comparison subjects. Clinical outcome was assessed after nortriptyline treatment. Of the 18 depressed patients, 16 were considered responders 4–6 months after initial assessment. A median split was used to classify response, and the pretreatment EEG data of patients showing better (N=9) and worse (N=9) responses were analyzed with low-resolution electromagnetic tomography, a new method to compute three-dimensional cortical current density for given EEG frequency bands according to a Talairach brain atlas. Results: The patients with better responses showed hyperactivity (higher theta activity) in the rostral anterior cingulate (Brodmann’s area 24/32). Follow-up analyses demonstrated the specificity of this finding, which was not confounded by age or pretreatment depression severity. Conclusions: These results, based on electrophysiological imaging, not only support hemodynamic findings implicating activation of the anterior cingulate as a predictor of response in depression, but they also suggest that differential activity in the rostral anterior cingulate is associated with gradations of response.

Sleep and Behavior Problems in School-Aged Children

Abstract: Objectives. The primary purposes of the present study were to survey the prevalence of sleep problems in school-aged children and to examine these associations with parental perception of sleep problems, medical history, and childhood psychopathology. Methods. Sleep and medical history questionnaires and the Child Behavior Checklist were administered to the parents of 472 children between ages 4 and 12 years receiving routine pediatric care from urban, rural, and suburban pediatric practices. Results. Although sleep problems were reported for 10.8% of the sample during the past 6 months, less than one half of the parents who identified sleep problems reported that they had discussed sleep with their child9s pediatrician. The best predictor of current sleep problems was a history of sleep problems before age 2 years. Sleep problems such as snoring, tiredness during the day, and taking excessive time to fall asleep were very common, occurring at least 1 night per week in over 20% of the total sample. Factor analysis of the sleep problems questionnaire resulted in 5 sleep problem factors that accounted for 58.7% of the variance. Specific sleep problem factors include: parasomnias, enuresis/gags, tiredness, noisy sleep, and insomnia. Sleep problem factor scores were differentially associated with medical history variables and measures of childhood psychopathology. Children rated highly on parasomnias were more likely to have frequent falls and to display pica. Parasomnias and noisy sleep were inversely associated with socioeconomic status (SES). Children from lower SES families were rated higher on these factors than children from higher SES families. Enuresis/gags was the only sleep problem factor associated with age. Younger children scored higher on this factor. Duration of naps was highly correlated with age and with bed times during the week and weekends. As expected, younger children were more likely to nap for longer periods and to have earlier bed times. In addition, higher tiredness factor scores were associated with napping and with later bed times during the week and weekend. Boys were much more likely than were girls to have higher scores on enuresis/gags, and higher enuresis/gags scores were associated with an increased prevalence of trauma and falls. Bed times were not associated with any other sleep problem factor score. Children rated highly on tiredness were more likely to have a history of hospitalizations. Tiredness factor scores were strongly associated with the sleep practice of sharing a bed but not with sharing a room. Sharing a room was not associated with any sleep problem factor score. High scores on noisy sleep were associated with allergies, falls frequently, and with sharing a bed. Children with high scores on the insomnias were also more likely to display an increased prevalence of allergies. Conclusions. Parental perception of global sleep problems was surprisingly common in school-aged children receiving routine pediatric care. Parental reports of their children9s sleep problems may be a red flag for specific sleep problems and psychiatric, social, or medical problems. Sleep problems should be queried about during pediatric visits for school-aged children.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The amygdala: vigilance and emotion

Abstract: Here we provide a review of the animal and human literature concerning the role of the amygdala in fear conditioning, considering its potential influence over autonomic and hormonal changes, motor behavior and attentional processes. A stimulus that predicts an aversive outcome will change neural transmission in the amygdala to produce the somatic, autonomic and endocrine signs of fear, as well as increased attention to that stimulus. It is now clear that the amygdala is also involved in learning about positively valenced stimuli as well as spatial and motor learning and this review strives to integrate this additional information. A review of available studies examining the human amygdala covers both lesion and electrical stimulation studies as well as the most recent functional neuroimaging studies. Where appropriate, we attempt to integrate basic information on normal amygdala function with our current understanding of psychiatric disorders, including pathological anxiety.