Designated HitterSeptember 17, 2009
Unraveling the Batter’s Brain
By Dave Baldwin

[Editor's Note: Dave Baldwin is a former MLB pitcher. He pitched for the Washington Senators (1966-1969), Milwaukee Brewers (1970), and Chicago White Sox (1973). His best season was 1967 when he posted an ERA of 1.70 with 12 saves. Dave has been a member of the Society for American Baseball Research since 2002.]

Part of any pitcher’s job is to understand what goes on in the murky, cobwebby recesses of a batter’s head as the ball is hurtling toward the catcher’s mitt. In fact, this is a pitcher’s most formidable task because the wiring of the batter’s brain is a neuronal mishmash, poorly understood even by the best of baseball’s neuroscientists.

But let’s not be too hard on the batter’s poor brain—it is asked to do an incredibly tough job. During the first two-thirds of the pitch’s flight, the batter simultaneously collects information and performs critical calculations with respect to the ball’s trajectory. From these calculations, he predicts where and when the ball will be at the potential point of impact with the bat. When the ball is approximately twenty feet from the ball/bat contact point, a decision is made and the batter commits to taking the pitch or swinging. That decision is absolutely irreversible if the batter is taking, and if the batter is swinging, he can’t change the trajectory of the bat’s sweet spot (although he can still attempt to check the swing by pulling his hands against his body).

So Little Time

A good fastball traveling at, say, 90 miles per hour (mph) takes about four-tenths of a second or 400 milliseconds (msec) to get from pitcher’s hand to the contact point (assuming the pitcher releases the ball about five feet in front of the pitching rubber and contact is made about a foot in front of home plate). The batter’s noggin has about 270 msec or a little more than a quarter of a second to get its ducks in a row and start the swing. But, although the bat has started its journey, the batter’s conscious mind is still unaware that the batter has decided to swing.

How do we know this? In the 1970s, neurophysiologist Benjamin Libet conducted a series of experiments to determine the relationship between the conscious intention to carry out an action and the initial brain activity that must precede the action. He found that the brain lights up about 350 msec before the conscious mind is aware the action is to be taken (Libet, 1985; Libet, et al., 1983). But the batter’s brain has only 270 msec to decide whether and where to swing. If these decisions were to be made by the conscious mind, the ball would be in the catcher’s mitt before the batter could do little more than start moving the bat. In fact, the ball is only 50 msec (about seven feet) away from the contact point when the batter’s conscious mind finally realizes that he is swinging the bat. The batter can do nothing to alter the swing in that final 50 msec. Thus, he is hitting with his unconscious mind.

What we are calling the “conscious mind” is primarily the cerebral cortex. The “unconscious mind” comprises those brain components that collectively produce mental phenomena occurring without the person being aware of them. The ancient, deep-brain region called the limbic system (amygdala, hippocampus, hypothalamus, etc.) is a major part of the unconscious mind. It interacts with the cerebellum, a brain structure responsible for coordinating muscle activity during the batter’s actions. This is the same quick neural circuitry that tries to save a hiker who is the target of a rattlesnake’s strike. A hiker dodging a two and a half-foot strike of a five-foot snake has about 200 msec to come to the conclusion to jump—even less time than is granted the batter, but the hiker’s problem is much simpler, of course.

What the Batter's Brain Must Do

Let’s consider the steps the batter’s brain must take during those critical 270 msec. First, the unconscious apparatus must gather information about the behavior of the ball. If it fails in this initial task, the batter might just as well go up to the plate with a wet noodle instead of a bat.

The batter needs to begin collecting pitch information as soon as possible. To prepare for this “quick read,” the batter’s conscious mind concentrates on an imaginary “box” where he expects the pitcher’s release point to be. Thus, his cerebral cortex is thoroughly occupied and doesn’t hinder the unconscious mind. If he has guessed correctly and the ball is released from that box, he can begin to evaluate the pitch as it leaves the pitcher’s hand. Otherwise, the batter must spend precious milliseconds searching for the ball.

Not only must the batter predict where the ball will be at the instant of bat/ball contact but when the ball will arrive there, as well. To do this, the batter observes the trajectory and calculates the rate at which it is changing in each of the spatial dimensions. The visual parameters used by the batter to accomplish this are the apparent size of the ball’s image (used to estimate distance to the ball), distance of the image off the foveae of the batter’s retinas, and the horizontal angles of the right and left eyes. The time until bat/ball contact is calculated by the ratio of the image's apparent size to the rate of change of this size. These calculations are performed without the batter’s awareness.

During the early stage of the trajectory, the image seems to be coming very nearly directly at the batter’s eyes, but as the ball gets closer to the contact point, the horizontal angles of the eyes expand, and the eyes have increasing difficulty keeping the image on the foveae. In fact, the eyes aren’t able to follow the pitch all the way to the ball/bat contact—the image “outruns” the foveae when the ball is about five feet from the contact point (Bahill & Baldwin, 2004). This doesn’t matter since the batter can do nothing at that point to alter the trajectory of the bat’s sweet spot. During the last five feet of the pitch’s flight, the batter would do just as well if he had his eyes closed.

Note that the ball “appears” to approach the contact point more rapidly in the later stages of its flight, even though the 90 mph pitch actually slows by about eleven and a half mph because of drag force during the flight. The batter’s mind makes adjustments for this phenomenon. To experience this illusion, watch the median stripes on a highway as you travel at a constant speed of 60 mph. A stripe that is quite distant down the highway will seem to creep toward you, while a stripe very near the car will seem to whiz by, even though the car is moving at the same speed relative to the two stripes, of course.

Besides using the visual clues discussed above, the batter might also check out the ball’s spin pattern for indication of pitch behavior. Some batters report seeing a pattern of stripes (and maybe a dot) made by the red seam as it whirls around the axis of the ball; some say they can’t see anything but a gray blur. If a batter’s unconscious mind recognizes the spin of the pitch, it has information about the direction and magnitude of the ball’s spin-induced deflection (Bahill, et al., 2005). The trajectory of any spinning pitch (i.e., one that isn’t a knuckleball) will be deflected by the spin to some extent. Hitting a baseball is a skill of precision—the batter must adjust to even a slight deflection.

I surveyed fifteen former major league position players and found that only eight remember seeing the seam spin pattern. These results might indicate visual differences, or they might stem from variation in the way the pattern is processed and stored in the brain. Coaches generally assume that the ability to see the spin pattern will make for a better hitter, but the success of a batter doesn’t seem to be related to his ability to recall seeing this pattern. Using two Hall of Famers as examples, we note that Frank Robinson has reported he was able to see the seam, but Mike Schmidt has said he was never able to see it (Schmidt, 1994).

Taking Advantage of the Batter's Brain

How can the pitcher benefit from knowing how the batter’s brain works? For many decades pitchers have known how to “set up” the batter for an out pitch. The pitcher does this by using the residual image of the previous pitch to confound the hitter. This works because the image resides somewhere in the unconscious mind, retained in short-term memory. The pitcher sets up the batter by showing him a pitch—say, a high, inside, smoking fastball. The batter can’t help but maintain the memory for some short period—long enough to allow the pitcher, working quickly, to come back with an ever sooooo slooooow curve while smoke is still hanging around in the batter’s cranium. Psychologists call this “visual priming”—an earlier visual stimulus influences response to a later visual stimulus. Knowing how to set up the batter is an important part of knowing how to pitch.

The pitcher can also benefit from a distraction of the batter’s unconscious mind or from giving the cerebral cortex extra information to process, thus interfering with the unconscious operations. I once had a catcher who would, on occasion, toss a handful of dirt on the batter’s shoes just as the pitcher was releasing the ball. He would do this only on a crucial pitch at a crucial point in the game. This made the batter’s unconscious mind spend some milliseconds trying to deal with the surprise.

Another way to accomplish this is to startle the batter with a loud or threatening noise. A few pitchers in baseball history have developed the knack of giving out a resounding grunt just as they released the pitch. And I remember hearing of a catcher who, now and then, would blast the batter with an ear-splitting whistle at an opportune moment. Both of these tricks distracted the batter. The unconsciousness switches from processing visual information to handling the unexpected auditory information. This switch has some real-life practical applications, such as heeding the snorting of a charging rhinoceros.

Several pitchers have had success in giving the batter’s conscious mind plenty of time to make decisions. The “eephus” thrown by Rip Sewell in the 1930s and ‘40s, and Steve Hamilton’s “folly floater” of the ‘60s are prime examples of pitches that worked well in part because they allowed the batter’s clumsy cerebral cortex to get involved. These pitches were lobs that reached a height of twenty feet or more at the apex. Pitches tossed to such a height take more than a second to reach the potential contact point—long enough to give the cerebral cortex plenty of time to get wound around itself, pondering how to slant the swing.

This is a difficult problem because a swing angled with a slight uppercut (usually the most effective angle on a normal pitch) will cut perpendicularly across the path of the descending lob, making timing the swing extremely difficult. The best angle with respect to timing the lob is an acute uppercut, one that will result in a high pop-up if the batter manages to make contact. Anyone who has attempted to fungo line drives has realized that tossing the ball high makes the task very challenging. To avoid this dilemma, experienced fungo hitters, such as Jimmie Reese, would give the ball a very short toss and hit it when it is almost stationary, near its apex.

The batter’s mind usually fails to resolve the swing-angle problem of the lob. Late in his career Steve Hamilton told me that, although he had thrown the folly floater many times, it had resulted in a hit only once—Frank Howard, showing remarkable presence of mind, had tapped the pitch over the first baseman’s head for a looping single.

Researching the Batter's Brain

In this article we’ve seen that batters’ brains carry out very complex operations. Given the importance of the unconscious components of the batter’s mind, perhaps research into how they are affected by various performance enhancers would be appropriate. For example, we have evidence that some scents—those of lemon, peppermint, and cinnamon—have a beneficial affect on the cerebral cortex, resulting in improved performances in mental and physical tests (Zoladz, 2005), but little is known about how these or more powerful performance enhancing chemicals affect the unconscious mind. With advances in technology giving us extremely precise measurements of the pitch, the hitting process, and the concomitant patterns of neural activity, we might be able to learn a great deal about what happens in the batter’s unconscious mind. In the future, the batter’s box might become an indispensable neurophysiological laboratory.

Note: In this article, all times are rounded to the hundredth of a second, and distances are rounded to feet.


Bahill, A.T. and Baldwin, D.G. 2004. “The rising fastball and other perceptual illusions of batters.” In Biomedical Engineering Principles in Sports. G.K. Hung and J.M. Pallis, eds. NY: Kluwer Academic / Plenum. pp. 257-287.

Bahill, A.T., Baldwin, D.G., & Venkateswaran, J. 2005. “Predicting a baseball’s path.” American Scientist, 93(3):218-225.

Libet, B. 1985. “Unconscious cerebral initiative and the role of conscious will in voluntary action.” Behavioral and Brain Sciences, 8:529-566.

Libet, B., Gleason, C. A., Wright, E. W., and Pearl, D. K. 1983. “Time of conscious intention to act in relation to onset of cerebral activity (readiness-potential): The unconscious initiation of a freely voluntary act.” Brain, 106:623-642.

Schmidt, M. and Ellis, R. 1994. The Mike Schmidt Study: Hitting Theory, Skills and Technique. Atlanta: McGriff and Bell Inc.

Zoladz, P.R. and Raudenbush, B. 2005. “Cognitive enhancement through stimulation of the chemical senses.” North American Journal of Psychology, 7:125-140.

Dave Baldwin is a former pitcher, geneticist, and engineer. He is now retired and living in Yachats, Oregon. His memoir is described at


Dave, thanks for stopping by and writing this piece. Very insightful.

I wonder whether it would do more good than harm for a pitcher to vary his release point to upset the timing of the hitter.

And for hitters, since their unconscious minds are controlling their actions, one has to think that the feelings that we tend to ascribe to batters are manifested in different ways than we are aware of. Are actions of the unconscious mind synonymous with reflexive responses, and if so, to what extent can we consciously control our reflexes? Is a batter's swing so ingrained into him through repetition that only the characteristics of the pitch make a significant difference as to how the batter reacts? In more practical terms, can a hitter with his conscious mind efficiently change his swing's flight path to lift a fly ball in a sacrifice situation?

Very interesting article. I love the idea of a pitch so slow that it allows time for the batter's conscious mind to interfere.

Didn't Yogi Berra say you can't think when hitting?

That is why I like when actual baseball players write pieces like this. Very insightful.

The distinction between conscious and unconscious isn't quite as strong Dave makes it seem. I'm sure he just simplified for this audience. Your conscious mind can prepare and heavily influence how your "unconscious" mind will react. You can sit on a fastball, for instance. But in support of Dave's point, even if you prepare for a fastball after seeing 3 change-ups, there is still a task-switching cost that the batter can't fully eliminate.

Also, you live a lot of your life reacting with that "unconscious" part of your mind. When you turn a corner, and run into that cute girl who works down the hall, and she says, "Hi," the way you respond is driven by this "unconscious" mind. Will you say, "uuuuhhh" or something more articulate? Depends on what habits have been burned in.

Good summary, Dave!

Agreed—a very good article. I like the mix of research and anecdote. Thanks for this, Dave.

Fascinating stuff, Dave. I didn't know that a player could start swinging before his conscious mind had decided to - that is really amazing. I'd like to see that excuse after a batter strikes out on a pitch in the dirt - "It's not MY fault, my unconscious brain did it!"

If I were a pitcher the thing I would take from this article is that I should work fast. That seems to be the one thing I can control that will mess with the hitter's brain but won't mess with my delivery. Is there any research done on how fast a pitcher has to work in order to keep the phantom of the last pitch in the batter's short term memory and therefore interfering with his ability to react to the current pitch?

The distinction between consciousness and unconsciousness is fuzzy as cdm suggests. Unfortunately, we know more about rat brains than about human brains. Jeremy makes a good point that it is advantageous to the pitcher to vary his release point. And Aaron is correct that pitchers should work fast. John Sain was the White Sox's pitching coach when they picked up Jim Kaat, age 34, on waivers from the Twins. Sain convinced Kaat to work rapidly and vary the velocity of his pitches. Kaat was a twenty-game winner for the next two years he was with the Sox.

Orlando Hernandez tried an eephus on A-Rod once. It landed in the stands. Another good story is Pascual Perez, who made some of his living by mixing in an eephus, throwing it to Glenn Davis. Davis was a softball home-run champ prior to being a pro player; that one also ended up in the stands.