Timing our actions is something we do thousands of times a day without thinking twice—controlling our eyes to read this text or reaching out to pick up a cup. To understand timing, however, it is first necessary to draw the distinction between the concept of time and timing. Timing is a human-made physical means of measuring the passage of time (e.g., seconds, minutes, hours). How we perceive time, per se, is very different from how time is measured by a watch or clock. Although the brain has no known dedicated time receptors, we are still very adept at organizing and guiding our actions in space and time (timing our actions). Indeed our survival in the dynamic world we all live in requires that the timing of our actions involve some understanding or perception of the time remaining before something happens. Prospective information provides information about the current future, that is where we are going and how we will get there based on our current course of action. For example, when one is driving a car, the changing patterns of light picked up by the driver’s eyes will inform the driver about when to start braking so as to avoid colliding with the car in front. This is an example of how prospective information available in the world we live in can be used to allow us to act ahead of time. In other words, the perceptual information available to us is important in allowing us to successfully control the timing of our interactions with other moving objects or people who live in the same dynamic environment. Before discussing how to control the timing of our actions in sporting contexts, it is necessary to draw a distinction between different types of timing and illustrate how they relate to different types of temporal information.
Different Types of Motor Timing
Catching a ball, moving to a beat, and hitting a golf ball are all examples of actions that require precise timing. More specifically, the outcome of these actions will be determined by how well the unfolding movements are controlled with respect to either intrinsic or extrinsic temporal information specifying how the event is unfolding. For example, when catching a ball, continuous visual perceptual information specifying where the ball is going and when it is going to get there is extrinsically available in the ball’s unfolding trajectory. In this case, the temporal control of the movement is called extrinsic. That is to say the movement of the ball that is external to the person determines how and when one should move to get to the right place at the right time to catch it.
Alternatively, when clapping to a beat, the perceptual information available to guide the action is intermittent. The beat demarcates when the clap should take place but does not provide any continuous perceptual information specifying when the next beat will sound. As with all movements, the movement needs to start before the beat sounds (prospective control), so the hands come together as the beat sounds. The intermittent acoustic information available when the beat sounds is insufficient to time the movement of the hands. In this case, some other form of temporal information must be provided by the brain to allow one to get their limb to the right place at the right time to clap to the beat.
Finally, when golf putting or taking a penalty kick in rugby or soccer, neither the beginning nor the end of the movement is specified by any form of extrinsic temporal information. Instead, the timing of the putting movement or kicking action, which is crucial for determining the velocity of the club or foot at ball impact, must again be specified by some intrinsic neural mechanisms in the brain. In this case, the action is totally self-paced in that the player determines when to begin the action and how it should unfold. The spatial temporal dynamics of the club or leg movement largely determine the success of the action with the timing of all self paced actions being provided intrinsically.
This distinction in the different types of action timing is critical when considering skill-based learning in sport (e.g., interceptive type actions vs. self-paced). In the next section, a theory is presented for how the temporal information (intrinsic or extrinsic) provides a solid basis to guide the timing of actions in sport.
Theories for Timing Movement
A plethora of research has studied timing mechanisms in the brain when tapping along to a beat. These studies have used the tapping paradigm, focusing on the size and variability of temporal errors made when synchronizing taps with beats and when continuing to tap when the beat stimulus is removed. Although timing theories have emerged, they tend to be paradigm driven only explaining movement timing when tapping a finger not when dancing, catching, or striking a ball. For instance, when dancing, synchronization of body and limb movements is patterned (spatially) relative to the temporal structure imposed by the music. In other words, the timing of movements is neither temporal nor spatial but is spatiotemporal—how the limb position changes over time. This poses a genuine problem in the application of traditional timing models to the understanding of timing in the control or coordination of goal directed action.
Thus, to understand the concept of timing in the spatiotemporal context the notion of time needs to be reconceptualized. Instead of considering the brain representing time like a clock, it is more appropriate to think of time’s passage, or a time interval, as being represented by something that changes over time. That is, time can be considered more of an abstraction that emerges from the way things change over time, which resonates with James J. Gibson’s (1975) idea that “events are perceivable, but time is not.” It is therefore more prudent to consider that the spatiotemporal control of actions or timing of actions must inevitably be related to the perception of events. The theory presented here, tau-coupling theory, follows from this and hypothesizes that the perception of temporal information (either intrinsic or extrinsic) guides the timing of our movements.
Temporal Information
To understand how temporal information can guide the timing of movement, it is first of all important to describe what is meant by information. In the physical world, the way in which a spatial gap between a ball and a target closes provides robust temporal information that can be used to control the timing of an action. David Lee suggested that the time-to-closure (tau) of a motion gap (in this case the distance between the ball and the target) at its current closure rate provides powerful information for timing movement. Not only is tau simple, general, robust information, it is also prospective, offering temporal information about the time remaining until a gap is closed. The appeal of a prospective informational variable in the context of timing is that it allows for the preparation and initiation of an action ahead of time, something that is critical in all sporting contexts.
Although tau as described above can explain action timing in the extrinsic temporal control context like catching a ball, it does not explain how we can time our actions in cases where the temporal control is intrinsic, as in self-paced actions—putting a golf ball. Here no continuous perceptual temporal information is available to guide movements prospectively (e.g., kicking a stationary ball). This informational void has to be, therefore, filled by some internal dynamic temporal representation generated in the player’s brain that helps provides a temporal framework to guide the timing of their movement. Previous research has proposed a mathematical model where this temporal information is specified in the brain in a way that is similar to the specification of temporal information in the physical world, namely a changing neural quantity (firing rate or neural power) over time.
To control the timing of our actions, the theory proposes a simple robust solution where the way the movement changes over time (the movement τ–τm) is linked to the perception of the dynamic temporal information (the informational τ–τ-guide [τi]) generated by an event in the environment (extrinsic) or the brain (intrinsic). This dynamic temporal information therefore prescribes the temporal course of the movement so that the information and movement are coupled in such a way that τm=kτi (where k a constant represents the volitional control of movement). This theory explains parsimoniously how we control the timing of our movements through the principles of information movement guidance.
Improving Motor Timing
Learning a new self-paced skill, such as controlling the velocity of the club head when putting a golf ball different distances, is a difficult skill to master. The velocity of the club head can be controlled by varying the amplitude of the back or forward swing, the duration of the swing, or both of these parameters. In other words, the way the action unfolds over space and time to give a particular velocity can arise from a mixture of different space-time-action permutations. Being a self-paced action, as mentioned above, the temporal framework for this type of movement is intrinsic, generated within the brain, and is not directly accessible to the learner or the trainer. One exciting new way of looking at how the timing of these actions can be improved is by seeing how some form of extrinsic temporal information can be provided that specifies how the action should unfold over time. Recent research has shown that by externalizing the temporal framework within which an action takes place, movement variability can be significantly reduced and the consistency of the timing of the action be improved. Coaches and players seeking to improve the timing of self-paced actions should therefore consider the use of extrinsic temporal information that could help the player prepare and execute the timing of the action in a more consistent manner. Furthermore, the role of preperformance routines, often adopted by elite players to help form the temporal envelope within which a self-paced action unfolds, should also be carefully considered so they include some form of extrinsic temporal information that could significantly improve the outcome of that action. That is, adopting the aforementioned information–movement coupling approach to consider how the brain controls the timing of an action (intrinsic vs. extrinsic information) could lead to new advances in coaching techniques and greatly advance research and practice in the area of motor timing. Finally, for interceptive actions, the information that players use is emerging as critical for determining performance outcomes.
Recent studies debunk previous research that suggests that responding as quickly as possible is of primary importance. Instead, this research has shown that tuning into the right source of external information (e.g., the player’s centre of mass) that specifies an action relevant property (e.g., final running direction) and acting upon this information in the appropriate time frame determines expertise. It is acting in the right way at the right time that defines sports performance in handball, soccer, and rugby, not acting as quickly as possible. More research is now required to understand how coaches can educate players’ attention to enable them to tune into the right perceptual information that can be used to guide the timing of their actions.
References:
- Brault, S., Bideau, B., Kulpa, R., & Craig, C. M. (2012). Detecting deception in movement: The case of the sidestep in rugby. PloS ONE, 7(6), e37494. doi: 10.1371/ journal.pone.0037494
- Craig, C. M., Delay, D., Grealy, M. A., & Lee, D. N. (2000). Precision golf putting: Guiding the swing. Nature, 405, 295–296.
- Dessing, J. C., & Craig, C. M. (2010). Bending it like Beckham: How to visually fool the goalkeeper. PloS ONE, 5(10), e13161. doi: 10.1371/journal.pone.0013161
- Gibson, J. J. (1975). Events are perceivable but time is not. In J. T. Fraser & N. Lawrence (Eds.), The study of time, 2. New York: Springer.
- Lee, D. N. (1998). Guiding movement by coupling taus. Ecological Psychology, 10, 221–250.
- Wing, A. M., & Kristofferson, A. B. (1973). Response delays and the timing of discrete motor responses. Perception Psychophysics, 14, 5–12.
See also:
- Sports Psychology
- Motor Development