Abstract& The network of regions shown by functional imaging studies to be deactivated by experimental tasks relative to nominally more passive baselines (task < baseline) may reflect processes engaged during the resting state or ''default mode.'' Deactivation may result when attention and resources are diverted from default-mode processes toward task processes. Aging is associated with altered patterns of deactivation which may be related to declining resources, difficulties with resource allocation, or both. These possibilities predict that greater task demand, which increases deactivation levels in younger adults, should exacerbate age-related declines in allocating resources away from the default mode. The present study investigated the magnitude and temporal properties of deactivations in young and older adults during tasks that varied in their demand for cognitive control. Two versions of a verb generation task that varied in their demand for selection among competing alternatives were compared to word reading and a fixation baseline condition. Consistent with our hypothesis, greater deactivations were found with increasing demand. Young and older adults showed equivalent deactivations in the minimal selection condition. By contrast, age differences in both the magnitude and time course of deactivation increased with selection demand: Compared to young adults', older adults' deactivation response showed less sensitivity to demand. Demand-related changes in deactivation magnitude correlated with performance changes, suggesting that individual and group differences in deactivation have functional significance. &
Cognitive control requires the resolution of interference among competing and potentially conflicting representations. Such conflict can emerge at different points between stimulus input and response generation, with the net effect being that of compromising performance. The goal of this article was to dissociate the neural mechanisms underlying different sources of conflict to elucidate the architecture of the neural systems that implement cognitive control. By using functional magnetic resonance imaging and a verbal working memory task (item recognition), we examined brain activity related to two kinds of conflict with comparable behavioral consequences. In a trial of our item-recognition task, participants saw four letters, followed by a retention interval, and a probe letter that did or did not match one of the letters held in working memory (positive probe and negative probe, respectively). On some trials, conflict arose solely because of the current negative probe having a high familiarity, due to its membership in the immediately preceding trial's target set. On other trials, additional conflict arose because of the current negative probe having also been a positive probe on the immediately preceding trial, producing response-level conflict. Consistent with previous work, conflict due to high familiarity was associated with left prefrontal activation, but not with anterior cingulate activation. The response-conflict condition, when compared with high-familiarity conflict trials, was associated with anterior cingulate cortex activation, but with no additional left prefrontal activation. This double dissociation points to differing contributions of specific cortical areas to cognitive control, which are based on the source of conflict.
Despite clinical reports of cognitive deficits associated with cancer chemotherapy, the underlying brain mechanisms are not clear. This research examined selective attention and working memory using functional magnetic resonance imaging (fMRI) in women before chemotherapy for localized breast cancer. Patients were tested with an established selective attention and working memory task during fMRI. Compared with healthy controls, patients showed (a) bilateral brain activation in high-demand task conditions with recruitment of additional components of attention/working memory circuitry, and (b) less accurate and slower task performance. Results indicate compromised cognitive functioning before any chemotherapy and raise key questions for further research.
IntroductionThe prevalence of endometriosis and the need for treatment in the USA has led to the need to explore the contemporary cost burden associated with the disease. This retrospective cohort study compared direct and indirect healthcare costs in patients with endometriosis to a control group without endometriosis.MethodsWomen aged 18–49 years with endometriosis (date of initial diagnosis = index date) were identified in the Truven Health MarketScan® Commercial database between 2010 and 2014 and female control patients without endometriosis were matched by age and index year. The following outcomes were compared: healthcare resource utilization (HRU) during the 12-month pre- and post-index periods (including inpatient admissions, pharmacy claims, emergency room visits, physician office visits, and obstetrics/gynecology visits), annual direct (medical and pharmacy) and indirect (absenteeism, short-term disability, and long-term disability) healthcare costs during the 12-month post-index period (in 2014 US$). Multivariate analyses were conducted to estimate annual total direct and indirect costs, controlling for demographics, pre-index clinical characteristics, and pre-index healthcare costs.ResultsOverall, 113,506 endometriosis patients and 927,599 controls were included. Endometriosis patients had significantly higher HRU during both the pre- and post-index periods compared to controls (p < 0.0001, all categories of HRU). Approximately two-thirds of endometriosis patients underwent an endometriosis-related surgical procedure (including laparotomy, laparoscopy, hysterectomy, oophorectomy, and other excision/ablation procedures) in the first 12 months post-index. Mean annual total adjusted direct costs per endometriosis patient during the 12-month post-index period was over three times higher than that for a non-endometriosis control [$16,573 (standard deviation (SD) = $21,336) vs. $4733 (SD = $14,833); p < 0.005]. On average, incremental direct and indirect 12-month costs per endometriosis patient were $10,002 and $2132 compared to their matched controls (p < 0.005).ConclusionsEndometriosis patients incurred significantly higher direct and indirect healthcare costs than non-endometriosis patients.FundingAbbVie Inc.Electronic supplementary materialThe online version of this article (10.1007/s12325-018-0667-3) contains supplementary material, which is available to authorized users.
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