18 research outputs found
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers âŒ99% of the euchromatic genome and is accurate to an error rate of âŒ1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Correlates and Moderators of Change in Subjective Memory and Memory Performance
Aging researchers have long been interested in understanding individuals' subjective perceptions of their own memory functioning. Previous research has shown that subjective memory ratings are partly based on memory performance but also reflect the influence of other factors, such as depressive symptoms. The aim of the present study was to examine (1) longitudinal associations between trajectories of subjective memory and memory performance, (2) variables that predict levels of and changes in subjective memory and memory performance, and (3) variables that moderate associations between these constructs. We applied a latent growth curve model to four occasions of data from 15,824 participants of the Health and Retirement Study (HRS; mean age at baseline = 64.27 years, SD = 9.90; 58% women). Results revealed that latent changes in subjective memory were correlated with latent changes in memory performance (Ï = 0.49), indicating that participants who reported steeper declines of subjective memory indeed showed steeper declines of memory performance over time. Three major patterns of associations emerged with respect to predictors of subjective memory and subjective memory change. First, the level of memory performance showed stronger associations with age, gender, and education, whereas subjective memory was more strongly associated with subjective age and personality traits. For example, women performed better than men on the episodic memory test, but there were no gender differences in subjective memory. Also, older age was associated with steeper declines of memory performance but with less decline of subjective memory. Second, personality traits that predicted subjective memory intercepts did not predict subjective memory slopes. Third, the strength of associations between levels and slopes of subjective memory and memory performance varied as a function of gender, education, depressive symptoms, and personality traits. Conscientiousness moderated the relationship of the level of subjective memory to the level of memory performance, consistent with the hypothesis that persons high in conscientiousness more accurately monitor memory successes and failures. The results reinforce the importance of depressive symptoms as a predictor of subjective memory but also indicate that a broader perspective on the reasons why memory complaints have modest correlations with memory itself is needed.Peer Reviewe
Age and extraversion differences in heart rate reactivity during working memory tasks.
Research and theory have shown a link between heart rate reactivity during cognitive testing and extraversion in younger adults; however, similar work has not been conducted with older adults. This study was designed to explore age and extraversion-related differences in within-person heart rate (HR) reactivity during two working memory tasks of varying difficulty using a multi-level modeling approach. Across 570 total within-person assessments of continuous HR monitoring, 28 younger adults (M = 19.76, SD = 1.15) and 29 older adults (M = 71.19, SD = 6.63) were administered two working memory tasks (backward digit span and n-back). There were no age differences in reactivity during the backward digit span. However, similar to previous findings, on the more difficult n-back task, younger adults low in extraversion showed a trend toward higher HR reactivity than young adults high in extraversion. Interestingly, the older adults showed the opposite pattern in that lower extraversion older adults were less reactive than the higher extraversion older adults who showed the steepest increase in HR. The HR increase of the older adults high in extraversion may be an indication of higher engagement in this more difficult task. Individual differences in extraversion need to be taken into account when administering working memory tasks in older adults
Longitudinal associations of subjective memory with memory performance and depressive symptoms: Between-person and within-person perspectives.
Mnemonic Training in Older Adults: Effects of Age, Length of Training, and Type of Cognitive Pretraining
COVIDâ19 vaccine hesitancy: The synergistic effect of anxiety and proactive coping
Abstract Background This study sought to identify cognitive and behavioral predictors of COVIDâ19 vaccine hesitancy. Specifically, this study examined the effect of anxiety about developing COVIDâ19 and proactive coping behavior on the likelihood of reporting COVIDâ19 vaccine hesitancy in a sample of adults living in the United States. Methods An online survey of proactive coping strategies, anxiety related to developing COVIDâ19, and vaccine hesitancy was administered in October 2020 to 534 adults aged 21â79âyears old. Age, gender, race, selfârated health, years of education, COVIDâ19 knowledge, and perceived constraints were included as covariates. Results Over half of the study participants (56.7%) were COVIDâ19 vaccine hesitant. People who were less anxious about developing COVIDâ19 were more likely to be vaccine hesitant. A statistically significant COVIDâ19 anxiety Ă proactive coping interaction showed the odds of vaccine hesitancy was highest among individuals with low anxiety about developing COVIDâ19 and high proactive coping, whereas vaccine hesitancy was lowest among individuals with high COVIDâ19 anxiety and high proactive coping. Conclusion Results support a futureâoriented approach to public health outreach efforts regarding COVIDâ19 vaccines. Improvement of proactive coping skills and emphasis on the likelihood of contracting COVIDâ19 may be more effective in increasing vaccine uptake than simply restating scientific facts regarding safety or efficacy