This study investigated the relationship between insulin-resistance and constituent components of executive function in a sample of neurologically intact older adult subjects using the homeostasis model assessment (HOMA-IR) and latent factors of working memory, cognitive control and processing speed derived from confirmatory factor analysis. Low-density lipoprotein (LDL), mean arterial pressure (MAP), along with body mass index (BMI) and white matter hypointensity (WMH) were used to control for vascular risk factors, adiposity and cerebrovascular injury. The study included 119 elderly subjects recruited from the University of California, San Francisco Memory and Aging Center. Subjects underwent neuropsychological assessment, fasting blood draw and brain magnetic resonance imaging (MRI). Partial correlations and linear regression models were used to examine the HOMA-IR-executive function relationship. Pearson correlation adjusting for age showed a significant relationship between HOMA-IR and working memory (rp=−.18; p=.047), a trend with cognitive control (rp=−.17; p=.068), and no relationship with processing speed (rp=.013; p=.892). Linear regression models adjusting for demographic factors (age, education, and gender), LDL, MAP, BMI, and WMH indicated that HOMA-IR was negatively associated with cognitive control (r=−.256; p=.026) and working memory (r=−.234; p=.054). These results suggest a greater level of peripheral insulin-resistance is associated with decreased cognitive control and working memory. After controlling for demographic factors, vascular risk, adiposity and cerebrovascular injury, HOMA-IR remained significantly associated with cognitive control, with working memory showing a trend. These findings substantiate the insulin-resistance-executive function hypothesis and suggest a complex interaction, demonstrated by the differential impact of insulin-resistance on processing speed and specific aspects of executive function. (JINS, 2015, 21, 622–628)

Successful communication is integral to quality health care and successful nursing practice. Ten people who had been in hospital in the 12 months prior to the study and who had no functional speech at that time were interviewed about their communication experiences with nurses. Overall, these individuals experienced difficulties, some of which appeared to be related to a lack of augmentative and alternative communication (AAC) resources and a lack of knowledge of AAC among nurses. In addition, the participants noted that nurses did not always have the time or the skills to communicate effectively with them. The participants suggested strategies to improve communication interactions between patients with no or limited functional speech and nurses. These strategies include pre-admission briefing and training nurses about effective strategies for communicating with patients who are unable to speak, including the use of augmentative and alternative communication systems.

The objective of this study was to evaluate the maturity of three inhibitory mechanisms (end-inhibition, side-inhibition, and cross-orientation inhibition) in the striate cortex of kittens at 4 weeks postnatal. To accomplish this, we made extracellular recordings from area 17 neurons while presenting visual stimuli consisting of sinusoidal luminance gratings or composites of gratings. We then compared data from kittens relating to various characteristics of each inhibitory mechanism with data from adults. We find that end-inhibition, side-inhibition, and cross-orientation inhibition are all present in kittens, and all show signs of maturity by 4 weeks postnatal. We conclude that the development of these inhibitory mechanisms occurs relatively early, and may coincide with the development of excitatory properties.