Learning a language from inconsistent input: Regularization in child and adult learners.

When linguistic input contains inconsistent use of grammatical forms, children produce these forms more consistently, a process called 'regularization.' Deaf children learning American Sign Language from parents who are non-native users of the language regularize their parents' inconsistent usages (Singleton & Newport, 2004). In studies of artificial languages containing inconsistently used morphemes (Hudson Kam & Newport, 2005, 2009), children, but not adults, regularized these forms. However, little is known about the precise circumstances in which such regularization occurs. In three experiments we investigate how the type of input variation and the age of learners affects regularization. Overall our results suggest that while adults tend to reproduce the inconsistencies found in their input, young children introduce regularity: they learn varying forms whose occurrence is conditioned and systematic, but they alter inconsistent variation to be more regular. Older children perform more like adults, suggesting that regularization changes with maturation and cognitive capacities.

Methylene blue decreases mitochondrial lysine acetylation in the diabetic heart.

Diabetic cardiomyopathy is preceded by mitochondrial alterations, and progresses to heart failure. We studied whether treatment with methylene blue (MB), a compound that was reported to serve as an alternate electron carrier within the mitochondrial electron transport chain (ETC), improves mitochondrial metabolism and cardiac function in type 1 diabetes. MB was administered at 10 mg/kg/day to control and diabetic rats. Both echocardiography and hemodynamic studies were performed to assess cardiac function. Mitochondrial studies comprised the measurement of oxidative phosphorylation and specific activities of fatty acid oxidation enzymes. Proteomic studies were employed to compare the level of lysine acetylation on cardiac mitochondrial proteins between the experimental groups. We found that MB facilitates NADH oxidation, increases NAD+, and the activity of deacetylase Sirtuin 3, and reduces protein lysine acetylation in diabetic cardiac mitochondria. We identified that lysine acetylation on 83 sites in 34 proteins is lower in the MB-treated diabetic group compared to the same sites in the untreated diabetic group. These changes occur across critical mitochondrial metabolic pathways including fatty acid transport and oxidation, amino acid metabolism, tricarboxylic acid cycle, ETC, transport, and regulatory proteins. While the MB treatment has no effect on the activities of acyl-CoA dehydrogenases, it decreases 3-hydroxyacyl-CoA dehydrogenase activity and long-chain fatty acid oxidation, and improves cardiac function. Providing an alternative route for mitochondrial electron transport is a novel therapeutic approach to decrease lysine acetylation, alleviate cardiac metabolic inflexibility, and improve cardiac function in diabetes.

Predictors of behavioural health service use and associated expenditures: Individuals with TBI in Pinellas County.

OBJECTIVE: Traumatic brain injury (TBI) is a major public health concern. Such injuries often result in dramatic changes in the individual's life-course due to the associated complex co-morbidities. Limited research exists on the use and expenditures incurred for behavioural healthcare services post-TBI. This study examined predictors of behavioural service use, incarceration and associated expenditures for individuals with TBI. METHODS: Emergency Medical Services and Medicaid Claims data were used to identify individuals diagnosed with a TBI in Pinellas County, Florida, in FY 2005. Ten statewide and local administrative data sets from 2005-2008 were employed to determine subject's demographic characteristics, criminal justice encounters, behavioural health services use and associated expenditures. Average annual expenditures and use of mental health, substance abuse and criminal justice services over a 3-year period were determined. RESULTS: A total of 1005 individuals diagnosed with TBI were identified and, of these, 910 survived the 3-year period. Study participants were grouped into high and low behavioural health expenditure groups. Those in the high expenditure group were more likely to be male, white and to have received behavioural health services. CONCLUSIONS: This study provides new information about predictors of behavioural health service use and Medicaid expenditures for Floridians with TBI.

The relationship between phonological and auditory processing and brain organization in beginning readers.

We employed brain-behavior analyses to explore the relationship between performance on tasks measuring phonological awareness, pseudoword decoding, and rapid auditory processing (all predictors of reading (dis)ability) and brain organization for print and speech in beginning readers. For print-related activation, we observed a shared set of skill-correlated regions, including left hemisphere temporoparietal and occipitotemporal sites, as well as inferior frontal, visual, visual attention, and subcortical components. For speech-related activation, shared variance among reading skill measures was most prominently correlated with activation in left hemisphere inferior frontal gyrus and precuneus. Implications for brain-based models of literacy acquisition are discussed.

Attention and expectation in human predictive learning: the role of uncertainty.

Three localized, visual pattern stimuli were trained as predictive signals of auditory outcomes. One signal partially predicted an aversive noise in Experiment 1 and a neutral tone in Experiment 2, whereas the other signals consistently predicted either the occurrence or absence of the noise. The expectation of the noise was measured during each signal presentation, and only participants for whom this expectation demonstrated contingency knowledge showed differential attention to the signals. Importantly, when attention was measured by visual fixations, the contingency-aware group attended more to the partially predictive signal than to the consistent predictors in both experiments. This profile of visual attention supports the Pearce and Hall (1980) theory of the role of attention in associative learning.