Age-Related Changes in Children's and Adults’ Explanations of Interpersonal Actions

We investigated the content of children's and adults’ explanations of interpersonal actions. Participants were 5-, 7-, and 9-year-old children, as well as adults, who were presented with 8 stories containing either prosocial or antisocial target actions, and asked to explain why each actor performed that action. In half of the stories, an interpersonal event preceded the action. Children and adults provided situational and mental-state explanations, but mental-state explanations were especially common for antisocial actions not preceded by an interpersonal event. With increasing age, participants explained prosocial actions by referring to the actor's goals, but referred to the actor's emotions and beliefs to explain antisocial actions. Finally, adults were most likely to mention psychological goals. These results suggest that (a) elementary school children provide a variety of explanations for interpersonal events; (b) children use different types of explanations flexibly, depending on the context and nature of the target action; (c) the frequency of different types of explanations for interpersonal actions changes during childhood; and (d) between middle childhood and adulthood, the recognition of psychological goals increases greatly.     

Children's and Adults’ Judgments of the Certainty of Deductive Inferences,Inductive Inferences,and Guesses

Children and adults rated their own certainty following inductive inferences, deductive inferences, and guesses. Beginning in kindergarten, participants rated deductions as more certain than weak inductions or guesses. Deductions were rated as more certain than strong inductions beginning in Grade 3, and fourth-grade children and adults differentiated strong inductions, weak inductions, and informed guesses from pure guesses. By Grade 3, participants also gave different types of explanations for their deductions and inductions. These results are discussed in relation to children's concepts of cognitive processes, logical reasoning, and epistemological development.     

A treadmill and motion coupled virtual reality system for gait training post-stroke.

A virtual reality (VR)-based locomotor training system has been developed for gait rehabilitation post-stroke. The system consists of a self-paced treadmill mounted onto a 6-degrees-of-freedom motion platform. Virtual environments (VEs) that are synchronized with the speed of the treadmill and the motions of the platform are rear-projected onto a screen in front of the walking subject. A feasibility study was conducted to test the capability of two stroke patients and one healthy control to be trained with the system. Three VE scenarios (corridor walking, street crossing, and park stroll) were woven into a gait-training program that provided three levels of complexity (walking speed, slopes, collision avoidances), progression criteria (number of successful trials) and knowledge of results. Results show that, with practice, patients can effectively increase their gait speed as demanded by the task and adapt their gait with respect to the change in physical terrain. However, successful completion of tasks requiring adaptation to increasing demands related to speed and physical terrains does not necessarily predict the patient's ability to anticipate and avoid collision with obstacles during walking. This feasibility study demonstrates that persons with stroke are able to adapt to this novel VR system and be immersed in the VEs for gait training.