The Perceptual Illusion of Baseball's Rising Fastball and Breaking Curveball

The rising fastball and the breaking curveball are impossible according to principles of physics and physiology, yet many baseball players claim they exist. The simulation and model presented suggest that the rising fastball and breaking curveball are perceptual illusions caused by the batter misestimating the speed of the pitch. This model uses signals from known primary visual processes only. This model was enhanced by adding an acceleration term. The enhanced model more accurately predicts the position of the ball when it crosses the plate. These models are compared and contrasted to models by McBeath and Bootsma. Sensitivity analyses have shown that the model and simulation are robust with respect to their parameter values. The model is most sensitive to the estimated distance to the ball, and the simulation is most sensitive to the estimated speed of the pitch. According to principles of physics and physiology, a rising fastball is impossible. Yet most batters claim it exists; they say the ball sometimes jumps a foot, right in front of home plate, causing the ball to hop over their bat. Our simulation and model explain this contradiction. Although the numbers given in this article are for professional baseball players, the simulation and model apply to all players, right down to Little Leaguers. They can also be extended to cricket. The rising fastball could be defined as a pitch where the ball (a) jumps up, right in front of the plate, (b) crosses the plate above the pitcher's release point, (c) is going upward when it crosses the plate, or (d) falls less than would be expected due to gravity. By Definitions (b) and (c), a rising fastball could be thrown by a sidearm baseball pitcher or a softball pitcher, but not by an overhand baseball pitcher. For example, an overhand pitch is released about 6 ft (1.83 m) above the ground; if the ball crossed the plate higher than this it would not be a strike. And for the ball to be going upward when it crosses the plate, it would have to fall initially, and then near the end of its flight, experience an upward force that is greater than that of gravity. A force that opposes gravity is produced by the backspin on a fastball. However, the maximum spin rate ever measured for a human pitch, 2,300 revolutions per minute (rpm), would create a force only two thirds that of gravity (Watts & Bahill, 1990). So, although a fastball's lift from backspin may not

[1]  David N. Lee,et al.  A Theory of Visual Control of Braking Based on Information about Time-to-Collision , 1976, Perception.

[2]  D. Regan,et al.  Necessary conditions for the perception of motion in depth. , 1986, Investigative ophthalmology & visual science.

[3]  Robert G. Watts,et al.  Aerodynamics of a knuckleball , 1975 .

[4]  Keiji Tanaka,et al.  Integration of direction signals of image motion in the superior temporal sulcus of the macaque monkey , 1986, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[5]  S. McKee.  A local mechanism for differential velocity detection , 1981, Vision Research.

[6]  R. Bootsma,et al.  Timing an attacking forehand drive in table tennis. , 1990 .

[7]  David N. Lee,et al.  Visual Timing in Hitting An Accelerating Ball , 1983, The Quarterly journal of experimental psychology. A, Human experimental psychology.

[8]  D Regan,et al.  The relation between discrimination and sensitivity in the perception of motion in depth. , 1975, The Journal of physiology.

[9]  J T Todd,et al.  The perception of 3-dimensional affine structure from minimal apparent motion sequences , 1990, Perception & psychophysics.

[10]  Fred Sir Hoyle,et al.  The Black Cloud , 1957 .

[11]  A. Terry Bahill,et al.  Keep Your Eye on the Ball: The Science and Folklore of Baseball , 1990 .

[12]  P. McLeod.  Visual Reaction Time and High-Speed Ball Games , 1987, Perception.

[13]  Martin J. Steinbach,et al.  Aligning the eye to the actively or passively positioned hand , 1970 .

[14]  A. Bahill,et al.  Why can't batters keep their eyes on the ball? , 1984 .

[15]  Leonard Matin,et al.  Acuity of Visual Perception of Direction in the Dark for Various Positions of the Eye in the Orbit , 1966 .

[16]  D. Regan,et al.  Neurons in area 18 of cat visual cortex selectively sensitive to changing size: Nonlinear interactions between responses to two edges , 1979, Vision Research.

[17]  A. Terry Bahill,et al.  Smooth pursuit eye movements in response to predictable target motions , 1983, Vision Research.

[18]  G. Orban,et al.  Factors influencing velocity coding in the human visual system , 1984, Vision Research.

[19]  A. Terry Bahill,et al.  Bioengineering: Biomedical, Medical and Clinical Engineering , 1981 .

[20]  M. McBeath.  The Rising Fastball: Baseball's Impossible Pitch , 1990, Perception.

[21]  D. Regan,et al.  Looming detectors in the human visual pathway , 1978, Vision Research.

[22]  M. Cynader,et al.  Stereoscopic subsystems for position in depth and for motion in depth , 1979, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[23]  D Regan,et al.  Visual responses to changing size and to sideways motion for different directions of motion in depth: linearization of visual responses. , 1980, Journal of the Optical Society of America.

[24]  Digby Elliott,et al.  Vision and motor control , 1992 .

[25]  C. E. Peper,et al.  Chapter 12 Predictive Visual Information Sources for the Regulation of Action with Special Emphasis on Catching and Hitting , 1992 .

[26]  D Regan,et al.  Visual Judgements and Misjudgements in Cricket, and the Art of Flight , 1992, Perception.

[27]  Stephen P. Messier,et al.  Bat Dynamics of Female Fast Pitch Softball Batters , 1984 .

[28]  J T Todd,et al.  Visual information about moving objects. , 1981, Journal of experimental psychology. Human perception and performance.