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When listening to music, humans can easily identify and move to the beat. Numerous experimental studies have identified brain regions that may be involved with beat perception and representation. Several theoretical and algorithmic approaches have been proposed to account for this ability. Related to, but different from the issue of how we perceive a beat, is the question of how we learn to generate and hold a beat. In this paper, we introduce a neuronal framework for a beat generator that is capable of learning isochronous rhythms over a range of frequencies that are relevant to music and speech. Our approach combines ideas from error-correction and entrainment models to investigate the dynamics of how a biophysically-based neuronal network model synchronizes its period and phase to match that of an external stimulus. The model makes novel use of on-going faster gamma rhythms to form a set of discrete clocks that provide estimates, but not exact information, of how well the beat generator spike times match those of a stimulus sequence. The beat generator is endowed with plasticity allowing it to quickly learn and thereby adjust its spike times to achieve synchronization. Our model makes generalizable predictions about the existence of asymmetries in the synchronization process, as well as specific predictions about resynchronization times after changes in stimulus tempo or phase. Analysis of the model demonstrates that accurate rhythmic time keeping can be achieved over a range of frequencies relevant to music, in a manner that is robust to changes in parameters and to the presence of noise. [ABSTRACT FROM AUTHOR]

Young children not only need to learn how to perform isolated actions, but also temporally and spatially coordinated actions such as using a knife and fork. Routes to learning such coordinated actions include imitation and participation in joint action. However, little is known about the mechanisms guiding transmission of coordinated actions through observation and joint action performance. This paper reports an experiment comparing children’s tendency to imitate multiple, coordinated actions following demonstration by a single model acting bimanually (Bimanual Observation condition), two models performing the same actions jointly with one performing each hand action (Joint Observation condition) and a condition in which the child actively takes part in the joint action demonstration by performing one part in coordination with a partner (Joint Action condition). When children were subsequently left alone to perform the task independently, they were more likely to imitate both coordinated actions in the two observation conditions than in the Joint Action condition, with no difference between performance in Bimanual and Joint Observation conditions. It is argued that this is due to children being more able to form a global representation of both actions and the relations between the two when observing from a distance than when actively involved in the task. [ABSTRACT FROM AUTHOR]