Multitasking is a critical feature of our daily lives. Using a dual-task paradigm, this experiment explored adults’ abilities to simultaneously engage in everyday motor and cognitive activities, counting while walking, under conditions varying the difficulty of each of these tasks. Motor difficulty was manipulated by having participants walk forward versus backward, and cognitive difficulty was manipulated by having participants count forward versus backward, employing either a serial 2 s or serial 3 s task. All of these manipulations were performed in single-task conditions (walk only, count only) and dual-task conditions (walk and count simultaneously). Both motor performance variables (cycle time, stride length, walking velocity) and cognitive variables (counting fluency, counting accuracy) were assessed in these conditions. Analyses of single-task conditions revealed that both motor and cognitive manipulations predictably influenced performance. Analyses of dual-task performance revealed influences of motor and cognitive factors on both motor and cognitive performance. Most centrally, dual-task costs (normalized difference between single- and dual-task conditions) for motor variables revealed that such costs occurred primarily for temporal or spatiotemporal gait parameters (cycle time, walking velocity) and were driven by cognitive manipulations. Dual-task cost analyses for cognitive measures revealed negative dual-task costs, or dual-task benefits, for cognitive performance. Finally, the effects of dual-task manipulations were correlated for motor and cognitive measures, indicating dual-task performance as a significant individual difference variable. These findings are discussed with reference to theories of attentional allocation, as well as the possible role of auditory–motor entrainment in dual-task conditions.

Humans operate in complex environments where social interactions require individuals to constantly attend to people and objects around them. Despite the complexity of these interactions from a visuomotor perspective, humans can engage and thrive in social settings. The purpose of the current study was to examine the simultaneous influence of multiple social cues (i.e., ownership and the presence of a co-actor) on the processing of objects. Participants performed an object-based compatibility task in the presence and absence of a co-acting confederate.Participants indicated whether pictures of mugs (that were either self-owned or un-owned) were upright or inverted. The pictures appeared at one of two locations (a 'near' or 'far' location relative to the participant) on a computer screen laid flat on (parallel to) the tabletop. When present, the co-actor stood on the opposite side of the screen/table. Analysis of response times (RTs) indicated that the processing of objects was influenced by the object's ownership status, the presence of the co-actor, and where the object was located on the screen. Specifically, RTs for pictures of self-owned mugs were shorter than un-owned mugs, but only when the pictures were located at the 'near' location. Further, the presence of a confederate resulted in shorter RTs for pictures located at the 'near', but not the 'far' location. These findings suggest that when objects were placed at the 'far' location, the additional social cues of ownership and social context did not influence visuomotor processing of the objects.

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By early childhood, children possess clear expectations about how resources should be, and typically are, distributed, expecting and advocating for equal resource distributions to recipients. Moreover, recent evidence suggests that children may be able to use deviations from equality in resource distributions to make inferences about the nature of social relationships. Here, we investigated whether children use partiality in resource distributions displayed by adults toward children in third-party contexts to identify parent-child relationships, whether children anticipate preferential treatment based upon knowledge of third-party parent-child relationships, and whether children anticipate different emotional reactions to impartiality in resource distributions in parent-child interactions compared to neighbor-child interactions. Four-to seven-year-old children were presented with hypothetical vignettes about an adult character who distributed resources to two children either equally, or systematically favoring one child. By the age of 4, children used resource distribution partiality to identify an adult as a child’s parent, and also used these expectations to guide their anticipated emotional reactions to impartiality. By the age of 6, children were also more likely to anticipate partiality to be displayed in parent-child compared to neighbor-child relationships. The findings from the current study reveal that partiality in resource distributions acts as a valuable cue to aid in identifying and understanding social relationships, highlighting the integral role that resources play in children’s understanding of their social world. More broadly, our findings support the claim that children use cues that signal interpersonal investment to specify and evaluate parent-child relationships in third-party contexts.