Stream of Consciousness
Creating the present using prediction and integration
Sometimes our brain can’t seem to keep up with what’s going on. It might be as simple as trying to wake up in the morning, when your brain is still trying to catch up. At other times, you could be talking and suddenly can’t find the right word. It’s right there on the tip of your tongue, but it won’t come out. Maybe you’re too tired and burnt out to be fully productive at work, or you’re out with friends and can’t quite keep up.
It’s clear that there are limits to what the brain can accomplish at any given moment. It has to piece together all of the things happening at this very moment, everything we sense in the environment, manage our body, track the situation we’re in. It has to integrate all of these things in an instant to construct the current conscious moment, the ‘now’ that we experience.
Without this integration our consciousness may not exist at all. Every night we seem to disappear entirely as the brain changes modes and limits its inputs, closing off the bridge at the brain stem. The same thing happens when patients are put under general anesthesia before surgery. By blocking a significant amount of nervous signals, it somehow is able to induce a temporary coma making the brain unable to feel anything. When the drugs wear off, the consciousness magically returns.
A crucial part of integration, of our conscious and unconscious experiences, is timing.
Neural Runtime
Information travels along nerves and up the spinal cord to the brain from all parts of the body. They also travel from the brain towards the body when we move. All of this feels like it happens in an instant, yet they actually all happen at different times. Neural signals travel at speeds ranging from 0.5–2 m/s for pain signals upwards to 70–120 m/s for motor signals. The nerves in the face are much closer to the brain than the ones from the fingers and toes, and this difference in distance creates a difference in travel time. For someone 6 feet tall, it can take about 18ms from the feet compared to 1ms for a few inches in the head. That’s almost 20 times longer.
Timing is also highly affected by processing time. All the senses on the head, the eyes, ears, nose, and mouth don’t have to travel far to the brain, yet they all take different amounts of time. In foot races, a gun is used to start the race because it is processed faster than vision even though light travels faster than sound. Reaction times to sound can be up to 25% faster than sight. Vision is vastly more data-heavy than hearing. It takes in large amounts high resolution image data in a 2D plane on the retina very rapidly, in approximately 60–90 frames per second. Meanwhile, sound consists of only 1D frequencies across time. This is the same reason why video takes up so much more space on computers than audio. Sight is inherently spatial while hearing isn’t.
On top of this raw sensory reaction time, there are more complex assessments and skills that require even further processing. Listening to someone talking is different than reacting to a bang. Words require networks of language processing to interpret and extract meaning from the raw sound. It needs to travel to the appropriate regions, parse out the words, interpret the tone, and recognize the voice. The same happens with vision. It has to figure out color, size, shape, distance, and speed to determine what the objects are and how they are moving. Like computer algorithms, each has its own level of complexity and, therefore, its own algorithmic runtime.
Try taking this Stroop test for example.
This test forces a competition between your word recognition and visual recognition of color. It takes additional conscious effort to figure it out, dramatically slowing it down by up to double or triple the time.
Even more work is required when cross referencing multiple senses and movements. When we have a conversation, we are not only listening for words and tone, we are exchanging looks and facial expressions, gesturing with our hands and bodies, all while trying to keep track of what’s been said and come up with the right reply. We might also be eating at a cafe, walking in the park, or driving down the road. Some people may have brains that combine all of this information efficiently, while others can only pay attention to certain pieces, needing more focus and taking more time.
A difference of 10 or 20 or even 100 milliseconds may not seem like much, but it might be enough to trip over our own feet, spill a cup of coffee, or stumble over our own words. If each of the signals are not coordinated and synchronized properly, the resulting lag has real consequences on our perception and behaviors. This is even more critical for professional athletes. Pro baseball pitches travel at about 150 km/h and tennis serves about 180 km/h, and Olympic records can differ by less than 100 ms. These delays can be the difference between the Olympic podium or making that championship winning point.
The time it takes to react to such fast pitches and serves is, on average, less than half a second. This means reading the trajectory, moving to the right position, winding up, and aiming the swing. All of this processing takes so much time that simply reacting isn’t enough. It has to be predicted.
Mapping the Future From the Past
To see how this might work, we can look at a similar problem that happens in computer networks through a different kind of sport, e-sports.
In online shooters and fighting games, the timing of player inputs is crucial to making the matches fair. Each player may have different internet speeds at different distances away from game servers, so they all end up traveling to and from the servers at different times. Signals can also be lost along the way as packets get dropped due to imperfections in the network. The netcode coordinating all these variations in timing has to work impeccably in order for every player in a match to feel as if it was all happening at the same time. In order to pull this off it uses various tricks to distribute the computational processing needed. The heavier computation to render the world, the characters, and animations are loaded onto the client side, or the local machine playing the game. This allows the network traffic to be fast and lightweight, only sending the tiny input signals from button and keyboard clicks.
To actively adjust for timing differences, it has to resort to prediction algorithms. These algorithms anticipate what might happen next based on what happened before and try to synchronize what the players see on each client end. It includes various tricks to cover missing frames, continue to play animations while waiting for updates, and will also roll back certain frames once it confirms what really happened. The main goal is to account for slight variations in network traffic and come up with an integrated flow that is the least disruptive. When it all works, the players don’t even notice any of the magic happening in the background. The few frame adjustments happen in milliseconds that most gamers would never even notice and doesn’t limit the incredible reaction times of pros.
What allows professional athletes to perform superhuman reaction times is also due to their brain’s ability to make extremely accurate predictions. Professional tennis players have played countless matches over many years since childhood. They have been exposed to increasingly faster serves and different types of serves from all kinds of players. They’ve practiced bolting to the right position and swinging their racquet to make good returns countless times. All of these instances are drilled into their neural circuits, which not only improves their raw reaction time, but allows them to make otherworldly predictions about which serve is going to happen and how to best respond to it.
Every little cue from the type of opponent, how they toss the ball, how they wind up their swing, their feet positioning, are all taken in unconsciously to let the body respond with the highest chance of success. When this process is disrupted by conscious analysis or doubt, it casts negative impacts, dropping their overall performance. It is thought that conscious processing is slower and more expensive to execute because it is actively tuning attention to adjust to new and unexpected information. This makes conscious effort invaluable during training to build up those circuits, but it becomes detrimental during a live match. Their own mind becomes their foe.
This is why many athletes often develop superstitious level rituals. They bounce around on their feet, touch their face, click their equipment in a very specific sequence in order to quiet their thinking mind and let the automatic one take over. Many little things can interrupt this delicate balance though. Something in the equipment or clothing feeling a little off, going against a losing streak, or a persistent heckler in the crowd. Pros have to find ways to tune out these hacks into their conscious minds and let their automatic training shine through.
It’s All Coming Together
Whether a professional is stepping up to bat against the fastest pitches in the world, or trying to nail that perfect sequence of headshots, their inner psychology is working at full speed predicting, estimating, and reacting with great precision. Any slips during game day or any concerns from surrounding life events can throw off that timing. For the rest of us without a need for superhuman speed, the regular speed of the brain is still extremely impressive. It is able to synchronize all kinds of information, thoughts, and abilities together so seamlessly that it feels like everything is happening all at once. It creates an illusion of perfect timing that we never question. It never feels like there are any delays even though they are happening all the time.
One lesson we can learn from the pros, is that sometimes it is best to get out of our own way. Maybe we aren’t so bad at starting conversations, doing the work, or setting up dates, but when we start second guessing ourselves it makes us stumble. It interferes with the way we usually are, injecting extra processing, and introducing more brain lag. It lets the nerves take over and jumble everything up, making the game much harder to play than it really is. Learn to trust your training, reduce your doubt, and let yourself perform at its best.
Maybe we could all use a little ritual here and there to remind us to just let things happen and not overthink things.
At least once in a while.
