Objective To determine the relationship between hearing loss and cognitive function as assessed with a standardized neurocognitive battery. We hypothesized a priori that greater hearing loss is associated with lower cognitive test scores on tests of memory and executive function. Methods A cross-sectional cohort of 347 participants ≥ 55 years in the BLSA without mild cognitive impairment or dementia had audiometric and cognitive testing performed in 1990–1994. Hearing loss was defined by an average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear. Cognitive testing consisted of a standardized neurocognitive battery incorporating tests of mental status, memory, executive function, processing speed, and verbal function. Regression models were used to examine the association between hearing loss and cognition while adjusting for confounders. Results Greater hearing loss was significantly associated with lower scores on measures of mental status (Mini-Mental State Exam), memory (Free Recall), and executive function (Stroop Mixed, Trail Making B). These results were robust to analyses accounting for potential confounders, non-linear effects of age, and exclusion of individuals with severe hearing loss. The reduction in cognitive performance associated with a 25 dB hearing loss was equivalent to the reduction associated with an age difference of 6.8 years. Conclusion Hearing loss is independently associated with lower scores on tests of memory and executive function. Further research examining the longitudinal association of hearing loss with cognitive functioning is needed to confirm these cross-sectional findings.

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MYB-type transcription factors play a diverse role in plant development and response to abiotic stress. This study isolated a rice R2R3-type MYB gene, OsMYB2, and functionally characterized its role in tolerance to abiotic stress by generating transgenic rice plants with overexpressing and RNA interference OsMYB2. Expression of OsMYB2 was up-regulated by salt, cold, and dehydration stress. OsMYB2 was localized in the nucleus with transactivation activity. No difference in growth and development between the OsMYB2-overexpressing and wild-type plants was observed under normal growth conditions, but the OsMYB2-overexpressing plants were more tolerant to salt, cold, and dehydration stresses and more sensitive to abscisic acid than wild-type plants. The OsMYB2-overexpressing plants accumulated greater amounts of soluble sugars and proline than wild-type plants under salt stress. Overexpression of OsMYB2 enhanced up-regulation of genes encoding proline synthase and transporters. The OsMYB2-overexpressing plants accumulated less amounts of H2O2 and malondialdehyde. The enhanced activities of antioxidant enzymes, including peroxidase, superoxide dismutase, and catalase, may underlie the lower H2O2 contents in OsMYB2-overexpressing plants. There was greater up-regulation of stress-related genes, including OsLEA3, OsRab16A, and OsDREB2A, in the OsMYB2-overexpressing plants. Microarray analysis showed that expression of numerous genes involving diverse functions in stress response was altered in the OsMYB2-overexpressing plants. These findings suggest that OsMYB2 encodes a stress-responsive MYB transcription factor that plays a regulatory role in tolerance of rice to salt, cold, and dehydration stress.