Andrew Pruszynski
@andpru.bsky.social
sports and neuroscience hot takes
Without having read it, I do think the OP paper takes the right approach. Have a network perform the task of interest and explore it as a means of generating hypotheses about how the brain does it and finding which tools would help you find out. "How does MotorNet do it" comes up a lot in our lab.
November 24, 2025 at 2:44 PM
Without having read it, I do think the OP paper takes the right approach. Have a network perform the task of interest and explore it as a means of generating hypotheses about how the brain does it and finding which tools would help you find out. "How does MotorNet do it" comes up a lot in our lab.
There is an ever growing set of tools available for dealing with population activity both in terms of describing it and, more interestingly I think, in terms of estimating the underlying dynamical structure. It is and will continue to be a challenge deciding which tool is right for which job.
November 24, 2025 at 2:22 PM
There is an ever growing set of tools available for dealing with population activity both in terms of describing it and, more interestingly I think, in terms of estimating the underlying dynamical structure. It is and will continue to be a challenge deciding which tool is right for which job.
I think Mark Churchland's recent review does a nice job of motivating how we got to where we are now in terms of population level descriptions with respect to motor cortex. Its not clear to me that this should generalize across the brain and across all behaviors. www.nature.com/articles/s41...
Preparatory activity and the expansive null-space - Nature Reviews Neuroscience
How does motor-cortex activity well before movement not drive motor outputs? In this Review, Churchland and Shenoy detail how searching for answers transitioned the understanding of neural activi...
www.nature.com
November 24, 2025 at 2:03 PM
I think Mark Churchland's recent review does a nice job of motivating how we got to where we are now in terms of population level descriptions with respect to motor cortex. Its not clear to me that this should generalize across the brain and across all behaviors. www.nature.com/articles/s41...
Dimensionality reduction on population activity is very useful but I have not been of the view that PCA (or whatever) *is the mechanism* so the issue of low/high-D has not been particularly bothersome to me -- some have taken strong stances on low-D and received lots of push back at the time.
November 24, 2025 at 2:00 PM
Dimensionality reduction on population activity is very useful but I have not been of the view that PCA (or whatever) *is the mechanism* so the issue of low/high-D has not been particularly bothersome to me -- some have taken strong stances on low-D and received lots of push back at the time.
I am just talking about his specific view on muscle synergies. Not EPH in general. Like he breaks it out here: pubmed.ncbi.nlm.nih.gov/20702893/
Motor synergies and the equilibrium-point hypothesis - PubMed
The article offers a way to unite three recent developments in the field of motor control and coordination: (1) The notion of synergies is introduced based on the principle of motor abundance; (2) The uncontrolled manifold hypothesis is described as offering a computational framework to identify and …
pubmed.ncbi.nlm.nih.gov
November 23, 2025 at 7:06 PM
I am just talking about his specific view on muscle synergies. Not EPH in general. Like he breaks it out here: pubmed.ncbi.nlm.nih.gov/20702893/
For sure. I'm not saying there is no physiological constraints on coactivation patterns (we've studied these in stretch reflexes for example and they can get very functional). Just that not every coactivation pattern (perhaps even not many) reflect such constraints.
November 23, 2025 at 7:03 PM
For sure. I'm not saying there is no physiological constraints on coactivation patterns (we've studied these in stretch reflexes for example and they can get very functional). Just that not every coactivation pattern (perhaps even not many) reflect such constraints.
Wouldn't Latash basically agree (if you didn't say OFC our loud)?
November 23, 2025 at 6:54 PM
Wouldn't Latash basically agree (if you didn't say OFC our loud)?
Yeah different lingo aside I think I mostly agree with Latash's views on muscle synergies. Though it's been a while since I have looked.
November 23, 2025 at 6:50 PM
Yeah different lingo aside I think I mostly agree with Latash's views on muscle synergies. Though it's been a while since I have looked.
Yeah, OFC or even simpler optimization schemes... like we showed here basically any cost function that penalizes energy gets you synergies because of multi-articular muscles. journals.physiology.org/doi/full/10....
Primate Upper Limb Muscles Exhibit Activity Patterns That Differ From Their Anatomical Action During a Postural Task | Journal of Neurophysiology | American Physiological Society
The present study examined muscular activity in the primate proximal forelimb during a posture task. By applying loads selectively to the shoulder, elbow, or both joints, we observed that monoarticula...
journals.physiology.org
November 23, 2025 at 6:37 PM
Yeah, OFC or even simpler optimization schemes... like we showed here basically any cost function that penalizes energy gets you synergies because of multi-articular muscles. journals.physiology.org/doi/full/10....
The fact low dimensional patterns are often observed doesn't mean they are the organizing principle per se. Lots of synergy work actively confuses the analysis/description for the mechanism. Can get synergies (systematic muscle activation correlations) when optimizing a range of cost functions.
November 23, 2025 at 6:27 PM
The fact low dimensional patterns are often observed doesn't mean they are the organizing principle per se. Lots of synergy work actively confuses the analysis/description for the mechanism. Can get synergies (systematic muscle activation correlations) when optimizing a range of cost functions.
It depends on your specific hypothesis/question.
November 23, 2025 at 4:43 PM
It depends on your specific hypothesis/question.
Synergies as description sure, synergies as mechanism no. The same is true 'manifolds' for neural activity.
November 23, 2025 at 4:33 PM
Synergies as description sure, synergies as mechanism no. The same is true 'manifolds' for neural activity.
You can find the link to the preprint here. doi.org/10.1101/2025...
YouTube
www.youtube.com
November 23, 2025 at 4:11 PM
You can find the link to the preprint here. doi.org/10.1101/2025...
They can't learn to completely ignore hunger just like they can't learn to completely control some arbitrary neuron or set of neurons.
November 23, 2025 at 2:09 AM
They can't learn to completely ignore hunger just like they can't learn to completely control some arbitrary neuron or set of neurons.
That's true but (a) preprints are a release valve and (b) IME, a lot of good important things happen in these final moments. What's a few weeks when good projects take years?
November 16, 2025 at 2:41 AM
That's true but (a) preprints are a release valve and (b) IME, a lot of good important things happen in these final moments. What's a few weeks when good projects take years?
Sure, this is basically how I do it but ... perhaps outside the discussion, I really don't think this would save all that much time/effort on a study.
November 16, 2025 at 1:46 AM
Sure, this is basically how I do it but ... perhaps outside the discussion, I really don't think this would save all that much time/effort on a study.
I add sentences until the paper says what it needs to say. Its not clear to me what the bullet points are ... are you imagining 5 bullets or 200?
November 15, 2025 at 10:51 PM
I add sentences until the paper says what it needs to say. Its not clear to me what the bullet points are ... are you imagining 5 bullets or 200?
What would a paper in bullet points actually mean? If your paper has sentences that are not simply not needed you can remove them now.
November 15, 2025 at 9:15 PM
What would a paper in bullet points actually mean? If your paper has sentences that are not simply not needed you can remove them now.
You can find the paper itself here: www.nature.com/articles/s41...
Mental graphs structure the storage and retrieval of visuomotor associations - Nature Human Behaviour
Trach and McDougle show that motor responses can form part of structured, graph-like memory representations.
www.nature.com
November 14, 2025 at 4:20 PM
You can find the paper itself here: www.nature.com/articles/s41...