Effects of Bilingualism on Cognitive Processing in Adults.

The primary objective of this dissertation was to empirically test the implications of the code-switching hypothesis (Peal & Lambert, 1962) for nonlinguistic cognitive abilities in bilingual adults. It was hypothesized that bilinguals, by virtue of their ability to switching between two linguistic systems, may enjoy cognitive advantages in the nonlinguistic domain for tasks that require abilities related to language switching. It was postulated that the underlying mechanisms of code switching are the bilingual\u27s abilities to inhibit the processing of irrelevant information and activate previously suppressed information. To determine if a bilingual advantage exists for these abilities, bilingual and monolingual adults performed three nonlinguistic tasks designed to measure nonlinguistic task-switching, suppression of irrelevant information, and activation of previously suppressed information. While no differences in performance were observed between the linguistic groups on these tasks, methodological problems with two of the tasks prohibited a conclusive determination about the existence of bilingual advantages. A second objective of this dissertation was to examine bilingual adults\u27 language switching abilities and determine if there is a relationship between switch costs in the nonlinguistic and linguistic domains. Bilingual adults performed a language switching task and it was found that linguistic switch costs were positively correlated with nonlinguistic switch costs. The implications of this relationship are discussed in terms of the underlying mechanisms that are utilized for linguistic and nonlinguistic switching. Future directions for exploring bilingual advantages for cognitive processing and elucidating the relationship between nonlinguistic and linguistic switching abilities in adults are discussed

The Suggestibility of Older Witnesses

The present study compares younger and older adult witnesses’ susceptibility to misinformation. Previous research on the misinformation effect has not measured the relationship between the effect and individuals’ perceptions of their own memory abilities. Such perceptions, and general knowledge of one’s own memory processes, are referred to as “metamemory.” In order to examine the relationship between metamemory and the misinformation effect in the present study, participants also completed a questionnaire that assessed their perception of their memory functioning. Although older persons tend to perceive their memories as being faulty, the correlation between self-assessment of memory abilities and actual memory performance is relatively low (Zelinski, Gilewski, & Thompson, 1980). We therefore predicted that there would be a negligible relationship between participants’ self-assessed memory functioning and whether or not they were susceptible to misinformation, for both younger and older adults

Ezetimibe added to statin therapy after acute coronary syndromes

BACKGROUND: Statin therapy reduces low-density lipoprotein (LDL) cholesterol levels and the risk of cardiovascular events, but whether the addition of ezetimibe, a nonstatin drug that reduces intestinal cholesterol absorption, can reduce the rate of cardiovascular events further is not known. METHODS: We conducted a double-blind, randomized trial involving 18,144 patients who had been hospitalized for an acute coronary syndrome within the preceding 10 days and had LDL cholesterol levels of 50 to 100 mg per deciliter (1.3 to 2.6 mmol per liter) if they were receiving lipid-lowering therapy or 50 to 125 mg per deciliter (1.3 to 3.2 mmol per liter) if they were not receiving lipid-lowering therapy. The combination of simvastatin (40 mg) and ezetimibe (10 mg) (simvastatin-ezetimibe) was compared with simvastatin (40 mg) and placebo (simvastatin monotherapy). The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, unstable angina requiring rehospitalization, coronary revascularization ( 6530 days after randomization), or nonfatal stroke. The median follow-up was 6 years. RESULTS: The median time-weighted average LDL cholesterol level during the study was 53.7 mg per deciliter (1.4 mmol per liter) in the simvastatin-ezetimibe group, as compared with 69.5 mg per deciliter (1.8 mmol per liter) in the simvastatin-monotherapy group (P<0.001). The Kaplan-Meier event rate for the primary end point at 7 years was 32.7% in the simvastatin-ezetimibe group, as compared with 34.7% in the simvastatin-monotherapy group (absolute risk difference, 2.0 percentage points; hazard ratio, 0.936; 95% confidence interval, 0.89 to 0.99; P = 0.016). Rates of pre-specified muscle, gallbladder, and hepatic adverse effects and cancer were similar in the two groups. CONCLUSIONS: When added to statin therapy, ezetimibe resulted in incremental lowering of LDL cholesterol levels and improved cardiovascular outcomes. Moreover, lowering LDL cholesterol to levels below previous targets provided additional benefit