Our brain's ability to accurately perceive what is going on in the body depends on our mind's representation of said body via brain maps. Those who are well practiced at a particular skill have an appreciable gain in the cortical mapping of that area - think of a pianist and their hands - and are better able to modulate attention and reaction to stimuli in those areas. (I've discussed previously the large representation of the foot and hand in the brain and how to train them.)
On the flip side, the inability to discern right vs left in those with persistent unilateral pain is well established. As is the loss of 2-point discrimination and fine motor control in acute and chronic pain states. The brain maps can and do become distorted based on various stages of disuse and loss of non-threatening stimuli. They shrink and we can't access them as well - essentially they are blind spots on the map. Like we can't even visualize the body regions clearly. I think this happens even in uninjured people who become neurologically locked into specific patterns of movement such as the Left AIC or PEC in PRI-nomenclature. Interestingly, when the mind wanders and attentional focus is lost even our visuospatial system loses symmetry. These asymmetries become further facilitated with each movement that produces successful completion of a task - which only serves to make the existing pattern stronger and perpetuate the blind spots. This can become an issue for those seeking improved output and performance because the brain will not allow high force output to a body region that it does not feel can safely tolerate it - like areas with blind spots. I often see this in people who are segmentally strong but poor integrators.
I mean, we see this everyday as coaches and physios. Here's a test: pick a problematic movement or body region that you or your athlete is struggling with like a chronic ankle issue. Have them visualize the area without actually looking at it. I will typically utilize the body scan method. A body scan is a mindfulness technique used to bring attention and awareness to the body in a thorough and systematic way. Here's a script and here's a guided one I'll often use - I really like how Todd Hargrove describes it in his most excellent book A Guide to Better Movement.
Have them focus on mentally tracing the outline of the affected region - is it clear? Can they picture the nuances and anatomy of the region as well as they can on the other side? Typically, the weaker and non-dominant side (usually the left side) is fuzzy in the mental eye with blind spots and inaccuracies. The lumbar spine is also often poorly visualized likely because we struggle with segmental control here as well as it's smaller real estate in the homunculus (might this be why so many experience poor lumbopelvic control and often revert to an extension dominant patterning?).
I find this body scan both diagnostic and therapeutic (and it is not going soft, for all the meatheads out there isn't this what Arnold did when he talked about visualizing the peak of contractions and the pump). Finding these blind spots seems to nearly always correlate with a current or old injury region or area of decreased output. Often they can't feel sensory input as well and struggle with even identifying the space around the blind spots. It is truly fascinating to try this as you will find areas that are a general struggle to visualize despite the preconceived notions of self.
Improving one's awareness of the blind spots can improve attentional focus and potentially optimize motor output without inducing a maladaptive response - such as pain, anxiety, excess muscular tension. Because the brain has already "been there" and explored the region, the sensory input (whatever the mode) is likely much less threatening to the system. And it makes the outputs more efficient as found by the lead researchers in my former lab at PT school. The ability to shift attention from one body region to the other has been found to improve with practice and aids motor control by allowing the brain to recognize salient inputs for processing. Look, informational processing is what sets apart those who are robust high performers from the posers.
Think of this as an augmentation or extension of the movement practice. Most recommendations are for 10-20 minutes per day with a systematic toe to head approach using guidance (such as the script above) initially. Though I don't think we necessarily need to limit it to a separate time of day away from our movement practice. In fact this visualization can occur right before or during a big lift or planned movement - clearly visualizing the left hip and getting deep into left stance during a deadlift for example seems to help prime the nervous system. Just as true motor learning takes time, so does the ability to focus attention - but over time this becomes more automated and effective at shrinking the blind spots and maintaining healthy brain maps.
The bottomline is to seek out the blind spots and then gradually shrink them over time - improving performance in the process.
I get a high volume of questions regarding my recommendations on reading material. Like many of my colleagues and mentors, I'm a vociferous reader and love the feeling that comes from engaging in material from the minds of brilliant authors and curators. In order to save time and make it a bit more public, I have finally made a Recommended Readings page for this here website, which I'm pretty excited about.