The capacity to perceive and produce rhythmic patterns accurately is an important element of musical skill. As people age, deficits in some cognitive functions may lead to less accurate rhythmic performance. This article reviews studies on age-related changes concerning slowing of an internal timekeeping mechanism, effects of and memory deficits on temporal processing, and effects of practice in preserving accurate rhythmic performance. The assumption of a slower pacemaker in older people is supported by experiments using isochronous tasks. Slowing in polyrhythmic tasks, implicating the role of workload factors, suggests that timing in music involves more than automatic processes. Studies of the estimation of short temporal intervals generally converge to show that temporal judgments of elderly are less accurate than those of young adults, particularly in sharing conditions. Mere changes in the rate of the internal timekeeping mechanisms are insufficient to explain those results and suggest an interaction between more general changes in cognitive processes, such as reduction in resources, and deficits in working-memory. Studies of the benefits of continued practice in older professional musicians demonstrate that high levels of experience and practice preserve accurate rhythmic performance, thus partially compensating for age-related decline in processing speed and memory. Temporal and Nontemporal Information Processing in Music Music often is considered the art of Indeed, enters into both the production and perception of musical events (Jones, 1990, p. 213). Music perception and performance as cognitively demanding activities require that several categories of information be simultaneously processed. Some of them are more related to temporal processes than others, for example, rhythm versus melody. Musical time speaks to traditional psychological issues that are concerned with the production and perception of time. A number of researchers studying psychological time (Church, 1984;Michon, 1972;Treisman, 1963) have proposed that temporal information processing in humans is subserved by an internal clock-like mechanism. According to the internal clock model, time perception relies on an accumulation process, activated when the subject attends to time, and which counts the number of pulses produced by means of an internal time base during the interval to be evaluated. This model accounts principally for perception of the duration of external stimuli. Wing and Kristofferson (1973) proposed a two-process model to account for the performance of rhythmic tapping: An internal timekeeper emits pulses (timing process), each of which triggers a motor response (motor process). Thus the production of time intervals depends not only on actual physical duration but also on a variety of nontemporal factors, such as those related to motor implementation, Similarly, duration judgments cannot center on use of abstracted and isolated time intervals. For example, the so-called filled interval reveals that two identical time intervals may be perceived as different because of the information that fills them. This effect emphasizes the influence of nontemporal information on time judgments. Generally, studies examining the relationship between nontemporal factors and time perception and production often lead to different and contradictory results. The great variety of methodological approaches often makes the comparison of findings difficult. Nevertheless, good agreement exists between researchers that the judgment of duration cannot only be accounted for in terms of biological clocks or pacemakers and that a number of cognitive variables could affect a putative biological mechanism. As stressed by Craik and Hay ( 1999), a reasonable middle ground can be found in current models that embrace both biological and psychological factors. Thus, attentional models, which are basically extensions of models postulating the existence of an internal timer (pacemaker-accumulator), add an component, assuming that the internal timer requires attention to operate (B lock & Zakay, 1996; Zakay, 1989). …