Understanding Movement: How Your Brain Predicts Your Every Move
Have you ever wondered why you can't tickle yourself or why the world doesn't spin every time you move your eyes? It turns out your brain is constantly predicting your movements, and it does this through something called corollary discharge. Let's dive into what this fascinating theory means for you, your training, and your everyday life.
What Exactly is Corollary Discharge?
Corollary discharge is essentially your brain's way of saying, "Heads up! Movement incoming!" Every time you make a movement—whether you're lifting a barbell, running, or just blinking—your brain sends out two signals:
Motor command: Tells your muscles exactly what to do.
Corollary discharge (or efference copy): A special internal message sent to your sensory system to predict the upcoming movement.
This internal prediction helps your brain distinguish between sensations that you create (like the touch of your own hand) and sensations from the outside world (like someone else tickling you).
Everyday Examples You Didn't Realize
Why you can't tickle yourself: Your brain anticipates your own touch through corollary discharge signals, making the tickle sensation dull. But when someone else does it, it's unexpected, and you laugh. Teehehe.
Stable vision: Every time your eyes move, the scene in front of you shifts on your retina. Your brain uses corollary discharge to predict this shift, keeping your vision smooth and stable.
Your voice sounds different in recordings: When you speak, your brain predicts and slightly dampens the loudness of your own voice. Without corollary discharge (like when listening to a recording), your voice sounds louder or different to you.
How Corollary Discharge Affects Your Training
Understanding corollary discharge can help you get more out of your workouts in a few practical ways:
Perception of effort: Ever notice some days feel tougher than others? The intensity of your brain's corollary discharge signals helps determine how hard a workout feels. Improving mental strategies—like positive self-talk or visualization—can actually influence these signals, making your workouts feel easier and more manageable.
Coordination and balance: Your body anticipates movements, adjusting posture and coordination before you even begin. Training consistently improves your brain’s predictions, resulting in smoother, more precise movements. That’s why exercises like Olympic lifting or gymnastics become easier and more graceful with practice.
Skill learning: Your brain uses corollary discharge signals to compare what you intended to do with what actually happened. Errors between these predictions and reality help you refine your technique. This is exactly why practice makes perfect!
Fatigue: It's Not Just Your Muscles!
When you're tired during a workout, it's not just your muscles; your brain also feels fatigue. Higher effort requires stronger signals from your brain, making you feel mentally exhausted and affecting your performance. Techniques to manage mental fatigue (like mindfulness, good sleep, or even motivational music) can make a significant difference in your training outcomes.
Putting it into Practice at Coalition Strength & Conditioning
Here are some quick tips based on corollary discharge theory that you can start applying today:
Visualize your workouts: Mentally rehearsing movements can help your brain improve its predictions, making actual execution easier and smoother.
Listen to your body: Recognize when your effort feels unusually high—this might indicate your central nervous system needs recovery, not just your muscles.
Practice new skills often: Regular practice helps your brain refine its predictions, making movements more efficient and automatic.
Wrapping Up
Corollary discharge isn't just fascinating neuroscience—it's something you experience every moment you're awake. Understanding this theory can enhance your workouts, make your movements smoother, and deepen your awareness of how your mind and body work together.
Keep training smart, and remember: your brain is always one step ahead!
References
von Holst, E., & Mittelstaedt, H. (1950). Das Reafferenzprinzip. Naturwissenschaften, 37(20), 464–476. https://doi.org/10.1007/BF00622503
Sperry, R. W. (1950). Neural basis of the spontaneous optokinetic response produced by visual inversion. Journal of Comparative and Physiological Psychology, 43(6), 482–489. https://doi.org/10.1037/h0055479
Poulet, J. F., & Hedwig, B. (2007). New insights into corollary discharges mediated by identified neural pathways. Trends in Neurosciences, 30(1), 14–21. https://doi.org/10.1016/j.tins.2006.11.005
Blakemore, S. J., Wolpert, D. M., & Frith, C. D. (2000). Why can't you tickle yourself?. Neuroreport, 11(11), R11–R16. https://doi.org/10.1097/00001756-200008030-00002
Marcora, S. M. (2008). Do we really need a central governor to explain brain regulation of exercise performance? European Journal of Applied Physiology, 104(5), 929–931. https://doi.org/10.1007/s00421-008-0818-3
Wolpert, D. M., Ghahramani, Z., & Jordan, M. I. (1995). An internal model for sensorimotor integration. Science, 269(5232), 1880–1882. https://doi.org/10.1126/science.7569931