Background： Anecdotally, parents often report that children with attention deficit hyperactivity disorder （ADHD） who engage in regular physical activity （PA） experience positive behavioral changes. The purpose of...Background： Anecdotally, parents often report that children with attention deficit hyperactivity disorder （ADHD） who engage in regular physical activity （PA） experience positive behavioral changes. The purpose of this study was to examine this anecdotal relationship to provide preliminary evidence relevant to the potential benefits of PA on ADHD symptoms. Methods： Parents （n = 68） of children diagnosed with ADHD completed an lnternet survey assessing perceptions of how PA influences their child＇s symptoms. Results： A significantly greater percentage of parents reported that regular PA positively impacted symptoms. However, there were no uniform effects for all types of ADHD symptoms. The results indicate that there may be more positive benefits for symptoms of inattention and hyperactivity than for those of impulsivity. Conclusion： This is the first study to empirically document parents＇ perceptions of how PA influences ADHD and suggests that PA can be a viable strategy for reducing symptoms. PA may have greater benefits for specific symptoms of ADHD, providing critical information for developing PA interventions for children and adolescents.展开更多
Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed ...Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food （on a raised feeding platform） at either 1 or 4 m from the edge of forest cover （potential refuge）, in either the presence or absence of a nearby simulated predation threat （a sharp-shinned hawk Accipiter striatus model）. Compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds （primarily black-capped chickadees Poecile atricapillus） exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation （by refuging） and foraging gains in open habitat in a graded, threat-sensitive manner [Current Zoology 60 （6）： 719-728, 2014].展开更多
文摘Background： Anecdotally, parents often report that children with attention deficit hyperactivity disorder （ADHD） who engage in regular physical activity （PA） experience positive behavioral changes. The purpose of this study was to examine this anecdotal relationship to provide preliminary evidence relevant to the potential benefits of PA on ADHD symptoms. Methods： Parents （n = 68） of children diagnosed with ADHD completed an lnternet survey assessing perceptions of how PA influences their child＇s symptoms. Results： A significantly greater percentage of parents reported that regular PA positively impacted symptoms. However, there were no uniform effects for all types of ADHD symptoms. The results indicate that there may be more positive benefits for symptoms of inattention and hyperactivity than for those of impulsivity. Conclusion： This is the first study to empirically document parents＇ perceptions of how PA influences ADHD and suggests that PA can be a viable strategy for reducing symptoms. PA may have greater benefits for specific symptoms of ADHD, providing critical information for developing PA interventions for children and adolescents.
文摘Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food （on a raised feeding platform） at either 1 or 4 m from the edge of forest cover （potential refuge）, in either the presence or absence of a nearby simulated predation threat （a sharp-shinned hawk Accipiter striatus model）. Compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds （primarily black-capped chickadees Poecile atricapillus） exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation （by refuging） and foraging gains in open habitat in a graded, threat-sensitive manner [Current Zoology 60 （6）： 719-728, 2014].
