An especial skill is a unique case where one very specific variation of a motor skill exhibits a markedly superior task performance in comparison to performances on all other variations within the same skill class. This effect has been clearly demonstrated with basketball set shots from the regulation free-throw (foul) line, as well as with baseball pitches over the regulation pitching distance. To illustrate, as one moves closer to or farther from the basketball goal there is typically a consistent change in the percentage of shots made, with accuracy decreasing linearly as the distance to the target is increased. However, for highly practiced players, the shooting percentage is significantly better than expected at exactly 15 feet (4.57 meters) straight out from the basket—precisely at the foul line. It is reasoned that the especial skill effect emerges due to the massive amount of practice at that one variation of the skill relative to any other variant. The free-throw line is the only distance from which basketball players regularly and consistently practice set shots. This phenomenon is an example of the specificity principle of practice taking precedence over the generality principle of motor skill development. It is of particular interest because no current theories of motor control have been able to satisfactorily explain the intricacies of the especial skill phenomenon.
Specificity and Generality of Motor Skills
The notion of specificity of training in motor skill learning and performance is well established. The more that conditions of the performance task match those that were present during practice, the greater the transfer of benefits from training to test performance. The same shot from the same distance, with the same ball, under the same environmental conditions would be a classic example. The more those conditions are dissimilar, the less transfer is seen from training to test performance. It is reasoned that repeated training of the same skill under the same conditions builds up a strong memory representation for the correct motor action. Such a representation would be at best only partially correct if any condition for performing the skill was changed.
Specificity, therefore, poses theoretical problems because it would be essentially impossible for even an expert to practice every possible variation that they might encounter during motor skill challenges. Under most normal situations, every motor skill execution is subject to differing sensorimotor, contextual, or processing demands. To explain flexibility in performance, theories of generality (most prominently, Schmidt’s schema theory of motor skill learning) suggest that performers build up general representations for each class of movement skill. Through practice the skill is increasingly capable of being altered to match the demands of the task at any particular moment. The performer learns the common coordination pattern for the skill class, and then learns the rules by which forces and timing might be adjusted to create the skilled action for that situation. As the performer adds experience and practice, improvement is seen across the whole skill class. General motor program concepts can be used to explain, for example, how a basketball player can be accurate at jump shots from any one of numerous court positions under continuously changing dynamics of game play.
The most interesting feature of especial skills is that they seem to be an example of specificity emerging within a landscape of generality. All basketball players can shoot set shots (a shot where the feet do not leave the ground) with a general level of accuracy commensurate with their experience and the physical difficulty of the shot. All baseball pitchers can throw a straight fast-ball-style throw to a target of varying distances, again with accuracy varying according to experience and the physical demands of the throw. When the range of those variations is examined for patterns, theories of generality accurately account for performance outcomes. However, in the particular instance of a case that is special to that sport—the one that is practiced far beyond all others—the principle of specificity appears to take precedence.
Several theoretical explanations have been offered for the especial skill effect. The visual context hypothesis posits that certain consistent visual information, such as the particular angle of viewing, may enhance perception–action coordination under the one special condition. This concept received some support from research showing that 15-foot set shots at angles different than straight out from the basket did not produce the effect. However, other studies where the visual context was significantly altered have nonetheless demonstrated especial skills. The learned parameters explanation suggests that repeated practice of one variation of a skill leads to optimization of movement parameters, such as force, speed, or release angle, for that specific instance. This hypothesis has received some research support when weight of the ball was altered, but not supported in other research when the ball and distance were constant but changing the visual angle eliminated the effect (different viewpoint, but identical movement parameters). Another hypothesis is that experienced performers might develop a special general motor program used solely for the one massively practiced variation of the task. Hypothetically, this would be evidenced by kinematic information (relative angles, velocities, or accelerations of the involved joints and limbs) that shows unique coordination patterns for the especial skill in comparison to those common to the rest of the skill class. Yet, such kinematic analysis has failed to support this explanation with basketball shooting. Lastly, it has been suggested that the phenomenon might be simply a matter of confidence, rather than some difference in motor control per se. However, research has shown measures of performance efficacy to vary independently of the especial skill effect. In fact, such psychological measures call into question any cognitive (conscious processing) explanations. In sum, the phenomenon has yet to receive a fully satisfactory theoretical explanation.
The especial skill effect is interesting because it reflects high levels of practice or expertise, it may serve as a marker in the development of motor skill expertise, and it may highlight noncognitive aspects of human motor control.
- Breslin, G., Hodges, N. J., Kennedy, R., Hanlon, M., & Williams, A. M. (2010). An especial skill: Support for a learned parameters hypothesis. Acta Psychologica, 134, 55–60.
- Keetch, K. M., Lee, T. D., & Schmidt, R. A. (2008). Especial skills: Specificity embedded within generality. Journal of Sport & Exercise Psychology, 30(6), 723–736.
- Keetch, K. M., Schmidt, R. A., Lee, T. D., & Young, D. E. (2005). Especial skills: Their emergence with massive amounts of practice. Journal of Experimental Psychology: Human Perception and Performance, 31, 970–978.
- Simons, J. P., Wilson, J., Wilson, G., & Theall, S. (2009). Challenges to cognitive bases for an especial motor skill at the regulation baseball pitching distance. Research Quarterly for Exercise and Sport, 80(3), 469–479.