Several studies suggest infants and young children prefer prosocial over antisocial individuals and expect individuals will selectively approach prosocial rather than antisocial others. There is, however, confusion regarding (a) the methods used to assess preference versus those used to assess expectations and (b) the interpretation of previous studies. In the current study, utilizing eye-tracking technology, we dissect children and young adults' preferences and expectations after watching the hill paradigm, in which one character (the Helper) helps a protagonist ascend a hill whereas another character (the Hinderer) prevents the protagonist from doing so.Neither children nor young adults displayed a looking preference for the Helper over the Hinderer. With respect to expectations, children shown an animation in which the protagonist approached itsHelper looked significantly longer than children shown an animation in which it approached its Hinderer, whereas young adults' looking times were comparable across the two scenarios. We argue longer looking time to the Helper-approach animation may reflect that children expect the Helper to move in concert/coordination with the protagonist and are surprised when this does not occur. We discuss our findings in relation to arguments about boundaries between different techniques used to measure preferences versus expectations in developmental research. Highlights• We address whether clear boundaries exist between developmental paradigms that aim to test preferences, predictions, and expectations.• Eye tracking was used to collect data on children's and young adult's looking behaviour on a commonly used paradigm in social evaluation research.• We demonstrate that measures of preferences, predictions, and expectations can be extracted from a single paradigm and, therefore, that the boundaries between paradigms are far from clear cut.

In the past, researchers have shown that the individual components of episodic memory (i.e "what," "where," and "when") may emerge at different points in development. Specifically, while children as young as three can accurately report the "what" and "where" of an event, they struggle to accurately report when the event occurred. One explanation for children's difficulty in reporting when an event took place is a rudimentary understanding, and ability to use, temporal terms. In the current experiment, we employed a physical timeline to aid children's reporting of the order in which a series of episodic events occurred. Overall, while 4-, 5-, and 6-year olds performed above chance, 3-year olds did not. Our findings suggest that 3-year olds' limited ability to produce temporal terms may not be the rate-limiting step preventing them from identifying when events occurred in their recent past.

Individuals vary greatly in their willingness to select and persist in effortful tasks, even when high-effort will knowingly result in high-reward. Individuals who select and successively complete effortful, goal-directed tasks can be described as industrious. Trying to increase one’s industriousness is desirable from a productivity standpoint, yet intrinsically challenging given that effort expenditure is generally aversive. Here we show that in laboratory rats, a basic physical exercise regimen (20 min/day, five days/week) is sufficient to increase industriousness across a battery of subsequent testing tasks. Exercised rats outperformed their non-exercised counterparts in tasks designed to tax effort expenditure, strategic decision-making, problem solving and persistence. These increases in performance led to quicker reward obtainment and greater reward gain over time, and could not be accounted for simply by increased locomotor activity. Our results suggest that a basic exercise regimen can enhance effortful goal-directed behaviour in goal-directed tasks, which highlights a potential productivity benefit of staying physically active.

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Testing episodic foresight in children generally involves presenting them with a problem in one location (e.g., Room A) and, after a spending a delay in a different location, telling them they will be returning to Room A. Before they go, children are presented with a number of items, one of which will allow them to solve the problem in Room A. At around 3 to 4 years of age children display episodic foresight, selecting the item that will allow them to solve the problem. To date, however, no study has assessed whether 3- and 4-year-old children can plan beyond the very next event, selecting the correct item when there is a delay before returning to Room A. Here, we show that 3- and 4-year-old children can pass when a delay is imposed but that their performance is significantly worse than when they are planning for an immediate event.