Links between early baseline cortisol, attachment classification, and problem behaviors: A test of differential susceptibility versus diathesis-stress.

The purpose of the current study was to predict concurrent levels of problem behaviors from young children's baseline cortisol and attachment classification, a proxy for the quality of caregiving experienced. In a sample of 58 children living at or below the federal poverty threshold, children's baseline cortisol levels, attachment classification, and problem behaviors were assessed at 17 months of age. We hypothesized that an interaction between baseline cortisol and attachment classification would predict problem behaviors above and beyond any main effects of baseline cortisol and attachment. However, based on limited prior research, we did not predict whether or not this interaction would be more consistent with diathesis-stress or differential susceptibility models. Consistent with diathesis-stress theory, the results indicated no significant differences in problem behavior levels among children with high baseline cortisol. In contrast, children with low baseline cortisol had the highest level of problem behaviors in the context of a disorganized attachment relationship. However, in the context of a secure attachment relationship, children with low baseline cortisol looked no different, with respect to problem behavior levels, then children with high cortisol levels. These findings have substantive implications for the socioemotional development of children reared in poverty.

Rates of motorcycle helmet use and reasons for non-use among adults and children in Luang Prabang, Lao People's Democratic Republic.

BACKGROUND: Motorcycles make up 81 % of the total vehicle population and 74 % of road traffic deaths in Lao PDR. Helmets reduce the risk and severity of injuries resulting from motorcycle accidents by 72 %. Although Lao law mandates motorcycle helmet use among drivers and passengers, the prevalence of helmet use in Luang Prabang, Lao PDR is unknown. This project aimed to measure the prevalence of motorcycle helmet use among riders (i.e., drivers and passengers) in Luang Prabang. METHODS: An observational survey in Luang Prabang was conducted in February 2015 to measure the prevalence of motorcycle helmet use among drivers and passengers. Additionally, non-helmet wearing riders were surveyed to identify the reasons for helmet non-use. RESULTS: Of 1632 motorcycle riders observed, only 16.2 % wore helmets. Approximately 29 % of adults wore helmets while less than 1 % of all children wore helmets. When surveyed about attitudes towards helmet use, the majority of adult drivers indicated that they did not like how adult helmets feel or made them look. Additionally, almost half of motorcyclists who did not own child helmets reported that their child was too young to wear a helmet. CONCLUSIONS: Our finding that children wear helmets at significantly lower rates compared to adults is consistent with findings from neighboring countries in Southeast Asia. Results of this study have implications for public health campaigns targeting helmet use, especially among children.

Using digital images of the zebra finch song system as a tool to teach organizational effects of steroid hormones: a free downloadable module.

Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the ease of quantification and experimental manipulation, the zebra finch song system has great potential for use in undergraduate labs. Unfortunately, the underlying costs prohibit use of this system in undergraduate labs. Further, the time required to perform a developmental study renders such undertakings unrealistic within a single academic term. We have overcome these barriers by creating digital tools, including an image library of song nuclei from zebra finch brains. Students using this library replicate and extend a published experiment examining the dose of estradiol required to masculinize the female zebra finch brain. We have used this library for several terms, and students not only obtain significant experimental results but also make gains in understanding content, experimental controls, and inferential statistics (analysis of variance and post hoc tests). We have provided free access to these digital tools at the following website: http://mdcune.psych.ucla.edu/modules/birdsong.