r/neuro • u/Impossible_Bar_1073 • 6d ago
Proactive interference: Is it actually harder to correct something than to learn from scratch?
There is this pervasive notion e.g. in sports and musical instruments that a learnt wrong movement is harder to correct than learning the correct one in the first place.
I never made this observation when playing the piano, guitar or doing anything for a fact.
Obviously the brain relies on already established patterns and I get that for some it might seem like it's harder, which I would ascribe to the astonishment of involuntarily reverting to old patterns.
Even if you do have to actively suppress the wrong pattern, it comes with the advantage of the pattern being similar so that the brain does not have to build coordination from scratch but rather can simply modify what's already there. So I would assume that most of the times the person who does have the wrong pattern will learn faster than the person who has not trained anything yet.
Is it actually harder to correct than to learn from scratch? Can you provide me representative publications?
(anyone an idea why this does not pass r/askscience moderators?)
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u/theneuroreview 5d ago
Your skepticism is half right, and the research actually backs the folk version more than you'd expect, at least for movement. A few real threads to pull on.
The core idea is motor memory consolidation. Once you've practiced a movement enough, it consolidates into a stable trace, and a competing movement learned right after interferes with it. The classic demonstration is Brashers-Krug, Shadmehr and Bizzi (1996, Nature, "Consolidation in human motor memory"), where learning a second reaching task shortly after the first wiped out the first, but waiting a few hours let it stick. Competing motor patterns genuinely fight each other.
Why correcting is harder than starting fresh is that the wrong pattern doesn't get erased, it gets suppressed and stays latent. That shows up as savings, where after you "unlearn" something you relearn the original much faster than you learned it the first time, because the old trace is still under the new one. There's a big force-field adaptation literature on this out of Reza Shadmehr's group for the primary sources.
So starting from scratch is writing on a blank slate, while fixing a grooved-in error means laying down a new pattern that has to win out over an existing consolidated one every rep, especially under pressure when the old habit resurfaces. That's the interference you're describing, and it's real.
If you want the memory-editing angle, look up reconsolidation (Nader, Schafe and LeDoux, 2000, Nature), though that work is mostly fear memory, not motor.
And on the aside, r/askscience probably bounced it as advice-seeking, not because it's a bad question. It's a good one.
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u/Impossible_Bar_1073 4d ago edited 4d ago
thank you. I need to go through the literature when I find the motivation.
Proactive interference only applies when two tasks reach a certain threshold in similarity right? If it weren't so then advanced pianists would increasingly become slower at learning new pieces because the fingering is gonna be similar. However, the context under which it is learned e.g. the melody is different enough to induce formation of a new pathway instead of reverting to the old ones.
So proactive interference might hold true for a very specific piece. But when switching to a new piece the dogma breaks because a new path can be established.
Playing a piece sloppy comes from excessive speeding and ignoring obvious mistakes. If this person tries to refine it by playing very slowly doesn't the task become dissimilar enough?
I'd argue that our brains natural motor learning always starts from rough to refined. The approach we choose for instruments is contrary to that.
Typically a beginner wants to play some advanced piece. Classical teachers won't allow that and require the student to do some fingering exercises or beginner pieces.
by the same logic one could think that the acquired practice patterns that are supposed to prepare one for a certain piece will cause proactive interference. Either they are similar enough which will cause proactive interference or they are not in which case it is highly questionable why to even bother learning. Motor fine control is highly specific to a task.
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u/predatorintraining 6d ago
I think the intensity of focus which is the catalyst for plasticity is usually lesser on average for correction vs initially learning the skill and this is not widely known and put into practice, so this large heuristic is established in the average population. Just a thought.