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Analogies to stochastic optimization are common in developmental psychology, describing a gradual reduction in randomness over the lifespan. Yet for lack of concrete empirical comparison, there is ambiguity in how to interpret this analogy. Using data from n=281 participants ages 5 to 55, we show that "cooling off'" does not only apply to the single dimension of randomness. Rather, development resembles a stochastic optimization process in the space of learning strategies, which we characterize along key dimensions of reward generalization, uncertainty-directed exploration, and random temperature. What begins as large tweaks in the parameters that define learning during childhood, plateaus and converges in adulthood. The developmental trajectory of human parameters is strikingly similar to several stochastic optimization algorithms, yet we begin to observe a divergence around adolescence. Remarkably, none of the optimization algorithms discovered reliably better regions of the strategy space than adult participants, suggesting an incredible efficiency of human development.

Searching for information in a goal-directed manner is central for learning, diagnosis, and prediction. Children continuously ask questions to learn new concepts, doctors do medical tests to diagnose their patients, and scientists perform experiments to test their theories. But what makes a good question? What principles govern human information acquisition and how do people decide which query to conduct to achieve their goals? What challenges need to be met to advance theory and psychology of human inquiry? Addressing these issues, we introduce the conceptual and mathematical ideas underlying different models of the value of information, what purpose these models serve in psychological research, and how they can be integrated in a unified formal framework. We also discuss the conflict between short- and long-term efficiency of prominent methods for query selection, and the resulting normative and methodological implications for studying human sequential search. A final point of discussion concerns the relations between probabilistic (Bayesian) models of the value of information and heuristic search strategies, and the insights than can be gained from bridging different levels of analysis and types of models. We conclude by discussing open questions and challenges that research needs to address to build a comprehensive theory of human information acquisition.

Aims Dilated cardiomyopathy (DCM) associated with dystrophin gene (DMD) mutations in individuals with mild or absent skeletal myopathy is often indistinguishable from other DCM forms. We sought to describe the phenotype and prognosis of DMD associated DCM in DMD mutation carriers without severe skeletal myopathy. Methods and results At 26 European centres, we retrospectively collected clinical characteristics and outcomes of 223 DMD mutation carriers (83% male, 33 +/- 15 years). A total of 112 individuals (52%) had DCM at first evaluation [n = 85; left ventricular ejection fraction (LVEF) 34 +/- 11.2%] or developed DCM (n = 27; LVEF 41.3 +/- 7.5%) after a median follow-up of 96 months (interquartile range 5-311 months). DCM penetrance was 45% in carriers older than 40 years. DCM appeared earlier in males and was independent of the type of mutation, presence of skeletal myopathy, or elevated serum creatine kinase levels. Major adverse cardiac events (MACE) occurred in 22% individuals with DCM, 18% developed end-stage heart failure and 9% sudden cardiac death or equivalent. Skeletal myopathy was not associated with survival free of MACE in patients with DCM. Decreased LVEF and increased left ventricular end-diastolic diameter at baseline were associated with MACE. Individuals without DCM had favourable prognosis without MACE or death during follow-up. Conclusions DMD-associated DCM without severe skeletal myopathy is characterized by incomplete penetrance but high risk of MACE, including progression to end-stage heart failure and ventricular arrhythmias. DCM onset is the major determinant of prognosis with similar survival regardless of the presence of skeletal myopathy.

© 2020 by the American College of Cardiology Foundation., BACKGROUND: Takotsubo syndrome (TTS) occurs predominantly in post-menopausal women but is also found in younger patients. OBJECTIVES: This study aimed to investigate age-related differences in TTS. METHODS: Patients diagnosed with TTS and enrolled in the International Takotsubo Registry between January 2011 and February 2017 were included in this analysis and were stratified by age (younger: #50 years, middle-age: 51 to 74 years, elderly: $75 years). Baseline characteristics, hospital course, as well as short- and long-term mortality were compared among groups. RESULTS Of 2,098 TTS patients, 242 (11.5%) patients were #50 years of age, 1,194 (56.9%) were 51 to 74 years of age, and 662 (31.6%) were $75 years of age. Younger patients were more often men (12.4% vs. 10.9% vs. 6.3%; p ¼ 0.002) and had an increased prevalence of acute neurological (16.3% vs. 8.4% vs. 8.8%; p ¼ 0.001) or psychiatric disorders (14.1% vs. 10.3% vs. 5.6%; p < 0.001) compared with middle-aged and elderly TTS patients. Furthermore, younger patients had more often cardiogenic shock (15.3% vs. 9.1% vs. 8.1%; p ¼ 0.004) and had a numerically higher in-hospital mortality (6.6% vs. 3.6% vs. 5.1%; p ¼ 0.07). At multivariable analysis, younger (odds ratio: 1.60; 95% confidence interval: 0.86 to 3.01; p ¼ 0.14) and older age (odds ratio: 1.09; 95% confidence interval: 0.66 to 1.80; p ¼ 0.75) were not independently associated with in-hospital mortality using the middle-aged group as a reference. There were no differences in 60-day mortality rates among groups. CONCLUSIONS: A substantial proportion of TTS patients are younger than 50 years of age. TTS is associated with severe complications requiring intensive care, particularly in younger patients.