The development of children's action memory: When do actions speak louder than words?

Summary Although acting consistently has been found to improve memory, the reasons for this are unclear. In this investigation, we tested whether acting improves recall by integrating separate elements within an action into an organized whole and whether this process may be strategic. First graders, fourth graders, and college-aged adults listened to, acted out, or watched the performance of action-object phrases and then verbally reported or enacted the phrases. Phrases composed of transitive verbs were expected to be integrated more by action than phrases composed of intransitive verbs, and consequently recalled better, especially by the younger children. Recall increased between first and fourth grades, suggesting that some aspects of action memory may be strategic; however, there was no evidence that acting improves recall by means of integration. The pattern of results suggested that the nature of an action's outcome may contribute to the enactment effect.     

A broadband digitizing rat detector: Simultaneous recording from all sound frequencies in the range of rat ultrasonic vocalizations

A system is described that digitizes rodent vocalizations after the signals have passed through a spectrum analyzer. The system’s capacity to record simultaneously from all frequencies in a range selected by the experimenter is demonstrated. In the graphic display, both single and simultaneous multiple vocalizations of rats ranging freely in large experimental rooms are presented. The capacity of this system to record simultaneous vocalizations in a form that permits rapid analysis of many of the parameters of the signals is especially useful in the analysis of rodent social behavior.