Saccades are NORMAL ... but we sometimes perceive them as GLITCHES ... Doctor Andrew G. Lee explains how the brain succeeds and fails to track rapid movements of objects in our visual field by succeeding or failing to accommodate the natural twitch in our focussed attention
This experience is given an extra complication because the retina of the eye has a small blind spot quite close to the fovea, which is the part of the retina that sees things in extra fine detail when we are focussing.
Even after millions of years of evolution, the highly evolved brain cannot instantly respond to sudden changes ... there are always a few milliseconds of delayed reflex.
I experience this phenomenon every day in two contexts ...
ONE ... Watching a tiny tablet of sweetex dropping the short distance from the dispenser into a cup ... and seeing it twice in different positions rather than perceiving a smooth trajectory
and
TWO ... If I am painting, trying to follow a fine line with the fine tip of a sable paint brush ... and involuntarily allowing the hand that guides the brush to twitch as the eye re-adjusts its focus
https://en.wikipedia.org/wiki/Saccade
In the last few days I've been asking myself why my hand won't follow a smoothly drawn line ... I'm beginning to think that serious painters and calligraphers sometimes have to unlearn and re-program the involuntary processes that the mind might normally undertake.
Doctor Lee's excellent video is here on YouTube ...
https://www.youtube.com/watch?v=iIyEFTU3zOs
The next big question is ... how do surgeons cope ? ... or is this a trait that would disqualify someone from surgical practice ?
I asked ChatGPT about this problem and got a useful perspective ...
sccades ... are there any tricks that people who do very fine work, such as fine artists, or surgeons, can use to overcome the natural jerking movement of the eye ?
What you’re noticing is very real. The eyes don’t move smoothly most of the time. Instead, they make rapid jumps called Saccades, with brief stable periods in between called fixations. This creates a kind of “micro-jerkiness” in visual sampling that, at first glance, seems incompatible with extremely precise work.
Yet people like surgeons, watchmakers, and fine artists don’t eliminate this system. They learn to work with it, and in some cases, subtly train around its limits.
How experts deal with it
1. They rely on fixations, not motion
Precision happens during the still moments between saccades. Skilled practitioners naturally time their actions to coincide with these stable windows. For example, a surgeon placing a stitch or an artist drawing a fine line is effectively acting during a fixation, even if they aren’t consciously aware of it.
2. They slow down and segment tasks
Rather than trying to execute a long continuous motion under visual control, experts break actions into tiny chunks. Each micro-step is guided by a fresh fixation. This reduces the impact of the eye’s jumpy scanning.
3. They use “quiet eye” training
In fields like surgery and elite sports, researchers talk about the “quiet eye” phenomenon, where a person holds their gaze steadily on a critical point for slightly longer than average before acting. This improves accuracy and coordination. It’s not that saccades disappear, but their timing becomes more controlled.
4. They offload precision to the hands and tools
With practice, fine motor control becomes partly independent of continuous visual correction. Surgeons develop highly refined proprioception, and artists build muscle memory for strokes. Tools also help. Magnification systems, stabilizing rests, and robotic assistance all reduce reliance on rapid visual updates.
5. They control head and body movement
Minimizing larger sources of motion (like head sway or hand tremor) makes the small discontinuities of eye movement less disruptive. Many fine workers adopt very stable postures or brace their hands.
6. They use magnification and lighting strategically
Magnification doesn’t remove saccades, but it increases the amount of detail captured during each fixation. Better lighting reduces the need for frequent eye repositioning.
A subtle but important point
Your brain actively suppresses visual perception during saccades, a phenomenon known as Saccadic suppression. So you don’t actually see the blur or jump. Instead, your perception feels stable, stitched together from those fixation snapshots.
Experts are, in a sense, masters of this stitching process. They don’t fight the biology. They align their actions with it.
If you wanted to practice this yourself
People often improve fine visual precision by:
consciously pausing their gaze before acting
working slightly slower than feels natural
using reference points instead of continuous tracking
practicing under magnification (even simple reading glasses can help)
Over time, this builds a rhythm: look → stabilize → act → repeat.
It’s less about eliminating the “jerkiness” and more about learning the timing hidden inside it.
Of course, there is more to it ... the different sections of the human brain that process the perception of movement and the fine focussing functions ... are not simple !
https://www.youtube.com/watch?v=-gbMVjD3Bsw
https://www.youtube.com/watch?v=HBlRrUf29RE
