Performance on the Boston Naming Test in English-Spanish Bilingual Older Adults: Some Considerations

Gollan, Fennema-Notestine, Montoya, and Jernigan (this issue) present a timely and clinically relevant study that examines the impact of bilingualism on the performance on the Boston Naming Test in older adults. In light of the methodology employed, we weigh different potential interpretations of the findings and make recommendations for future studies. (JINS, 2007, 13, 212–214.

Assessing the progression of mild cognitive impairment to Alzheimer's disease: current trends and future directions

With the advent of advances in biomarker detection and neuropsychological measurement, prospects have improved for identifying and tracking the progression of Alzheimer's disease (AD) from its earliest stages through dementia. While new diagnostic techniques have exciting implications for initiating treatment earlier in the disease process, much work remains to be done to optimize the contributions of the expanding range of tools at the disposal of researchers and clinicians. The present paper examines recent work in cerebrospinal fluid biomarkers, magnetic resonance imaging, positron emission tomography, neuropsychological measures, and functional assessment. The strengths and weaknesses of current methodologies are explored and discussed. It is concluded that AD from its mild cognitive impairment state through dementia represents a continuous process, and that progression over time can best be accomplished by interval-level variables. Biomarkers that are most sensitive to early AD may not be the most optimal for monitoring longitudinal change, and it is likely that multivariate models incorporating cognitive measures, functional variables and biomarker data will be the most fruitful avenues for future research

Incentives in Health: Different Prescriptions for Physicians and Patients

Financial incentives abound in health care. They are found in the ways physicians are paid and in the ways health insurance coverage, co-payments, and deductibles are structured for patients. The effects of these incentives are often understood through conventional economic principles, with the assumption that individuals are self-interest maximizers who respond directly to changes in incentives. In contrast, behavioral economics imports insights from psychology and recognizes that individuals often do not respond to incentives as rationally as they might. In some cases, individuals lack information, but in others, they just seem to act contrary to their own known interests, for example, when they overeat, fail to take medication, or neglect to wear seat belts

Assessing Value in Health Care Programs

Many health care services provided in the United States are of low value, meaning that the cost of providing those services is high relative to the health care benefit they confer. In some cases, the care provided may have no value or even, on average, may be harmful. Examples of low- or negative-value services include unnecessary surgery or diagnostic imaging that will not change management. Given estimates that 30% of the $2.5 trillion the United States spends on health care services each year may provide little benefit,1 there is a widespread eagerness to enhance the ratio of benefits to costs

Failure to Recover from Proactive Semantic Interference Differentiates Amnestic Mild Cognitive Impairment and PreMCI from Normal Aging after Adjusting for Initial Learning Ability

Background: There is increasing evidence that the failure to recover from proactive semantic interference (frPSI) may be an early cognitive marker of preclinical Alzheimer’s disease (AD). However, it is unclear whether frPSI effects reflect deficiencies in an individual’s initial learning capacity versus the actual inability to learn new semantically related targets. Objective: The current study was designed to adjust for learning capacity and then to examine the extent to which frPSI, proactive semantic interference (PSI) and retroactive semantic interference (RSI) effects could differentiate between older adults who were cognitively normal (CN), and those diagnosed with either Pre-Mild Cognitive Impairment (PreMCI) or amnestic MCI (aMCI). Methods: We employed the LASSI-L cognitive stress test to examine frPSI, PSI and RSI effects while simultaneously controlling for the participant’s initial learning capacity among 50 CN, 35 aMCI, and 16 PreMCI participants who received an extensive diagnostic work-up. Results: aMCI and PreMCI participants showed greater frPSI deficits (50% and 43.8% respectively) compared to only 14% of CNparticipants. PSI effects were observed for aMCI but not PreMCI participants relative to their CN counterparts. RSI failed to differentiate between any of the study groups. Conclusion: By using participants as their own controls and adjusting for overall learning and memory, it is clear that frPSI deficits occur with much greater frequency in individuals at higher risk for Alzheimer’s disease (AD), and likely reflect a failure of brain compensatory mechanisms.Fil: Curiel, Rosie E.. University of Miami; Estados UnidosFil: Crocco, Elizabeth A.. University of Miami; Estados UnidosFil: Raffo, Arlene. University of Miami; Estados UnidosFil: Guinjoan, Salvador Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Nemeroff, Charles B.. University of Miami; Estados UnidosFil: Penate, Ailyn. Mount Sinai Medical Center; Estados Unidos. University of Miami; Estados UnidosFil: Piña, Daema. University of Miami; Estados UnidosFil: Loewenstein, David A.. Mount Sinai Medical Center; Estados Unidos. University of Miami; Estados Unido

Do Financial Incentives Reduce Intrinsic Motivation for Weight Loss? Evidence from Two Tests of Crowding Out

Financial incentives have been used successfully to promote health behaviors, however they may be counterproductive if they crowd out pre-existing intrinsic motivation and lead to a decrease in performance once incentives are removed to a level lower than they had never been introduced. We provide new evidence that incentives do not crowd out intrinsic motivation in the case of weight loss. We measure motivation via a survey administered before and after the introduction of financial incentives in two weight loss field experiments and find no evidence that intrinsic motivation fell among participants receiving incentives compared to control participants who do not receive incentives

Semantic Interference Deficits and the Detection of Mild Alzheimer’s Disease and Mild Cognitive Impairment Without Dementia

Impairment in delayed recall has traditionally been considered a hallmark feature of Alzheimer’s disease (AD). However, vulnerability to semantic interference may reflect early manifestations of the disorder. In this study, 26 mildly demented AD patients (mild AD), 53 patients with mild cognitive impairment without dementia (MCI), and 53 normal community-dwelling elders were first presented 10 common objects that were recalled over 3 learning trials. Subjects were then presented 10 new semantically related objects followed by recall for the original targets. After controlling for the degree of overall memory impairment, mild AD patients demonstrated greater proactive but equivalent retroactive interference relative to MCI patients. Normal elderly subjects exhibited the least amount of proactive and retroactive interference effects. Recall for targets susceptible to proactive interference correctly classified 81.3% of MCI patients and 81.3% of normal elderly subjects, outperforming measures of delayed recall and rate of forgetting. Adding recognition memory scores to the model enhanced both sensitivity (84.6%) and specificity (88.5%). A combination of proactive and retroactive interference measures yielded sensitivity of 84.6% and specificity of 96.2% in differentiating mild AD patients from normal older adults. Susceptibility to proactive semantic interference may be an early cognitive feature of MCI and AD patients presenting for clinical evaluation. (JINS, 2004, 10, 91–100.

Effect of Assessment Method on the Discrepancy between Judgments of Health Disorders People Have and Do Not Have: A Web Study

Three experiments on the World Wide Web asked subjects to rate the severity of common health disorders such as acne or arthritis. People who had a disorder (“Haves”) tended to rate it as less severe than people who did not have it (“Not-haves”). Two explanations of this Have versus Not-have discrepancy were rejected. By one account, people change their reference point when they rate a disorder that they have. More precise reference points would, on this account, reduce the discrepancy, but, if anything, the discrepancy was larger. By another account, people who do not have the disorder focus on attributes that are most affected by it, and the discrepancy should decrease when people make ratings on several attributes. Again, if anything, the discrepancy increased when ratings were on separate attributes (combined by a weighted average). The discrepancy varied in size and direction across disorders. Subjects also thought that they would be less affected than others

X-Ray Emission Line Ratios and Multiphase Gas in Elliptical Galaxies and Galaxy Clusters

We examine the K shell emission lines produced by isothermal and simple multiphase models of the hot gas in elliptical galaxies and galaxy clusters to determine the most effective means for constraining the width of the differential emission measure (xi(T)) in these systems which we characterize by a dimensionless parameter, sigma_xi. Comparison of line ratios of two-temperature (sigma_xi << 1) and cooling flow (sigma_xi ~1) models is presented in detail. We find that a two-temperature model can approximate very accurately a cooling flow spectrum over 0.5-10 keV. We have re-analyzed the ASCA spectra of three of the brightest galaxy clusters to assess the evidence for multiphase gas in their cores: M87 (Virgo), the Centaurus cluster, and the Perseus cluster. K-alpha emission line blends of Si, S, Ar, Ca, and Fe are detected in each system as is significant Fe K-beta emission. The Fe K-beta/K-alpha ratios are consistent with optically thin plasma models and do not suggest resonance scattering in these systems. Consideration of both the ratios of H-like to He-like K-alpha lines and the local continuum temperatures clearly rules out isothermal gas in each case. To obtain more detailed constraints we fitted plasma models over 1.6-9 keV where the emission is dominated by these K shell lines and by continuum. In each case the ASCA spectra cannot determine whether the gas emits at only two temperatures or over a continuous range of temperatures as expected for a cooling flow. The metal abundances are near solar for all of the multiphase models. We discuss the implications of these results and examine the prospects for determining the temperature structure in these systems with upcoming X-ray missions.Comment: 30 pages (18 figures), To Appear in MNRAS. Major revision of the initially posted version: (1) The section on ASCA data of ellipticals was expanded and moved to astro-ph/9811080; (2) The ASCA data of M87, Centaurus, and Perseus have been re-analyzed. We find evidence for Fe K-beta emission in these systems, but the Fe K-beta/K-alpha ratios do not suggest resonance scattering; (3) The metal abundances of the cores of these systems are consistent with the meteoritic solar value