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Sam McDougle

@actlab.bsky.social

psychology prof @yale http://actcompthink.org

290 Posts3310 Follower1188 Folgt
Reza Shadmehr@rezashadmehr.bsky.social · 2w ago

If an action results in error, each neuron requires an individualized teaching signal that guides change in its output. This is the credit assignment problem of learning. Are there neurons in the brain that can compute such a sophisticated teaching signal? Yes. www.biorxiv.org/content/10.6...

Climbing fibers encode the gradient of a loss function for the cerebellum

Neurons in the brain are often many synapses away from motoneurons, yet if a movement results in error, each distant neuron needs a teacher that considers its specific contribution to production of th...

biorxiv.org

Jeremy Hogeveen@jeremyhogeveen.bsky.social · 2w ago

Population geometry reveals largely distinct value-coding dimensions for saccades vs. reaches across 8 cortico-basal ganglia nodes—challenging motor-invariant RL models: doi.org/10.64898/202...

Embodied reinforcement learning in the primate cortico-basal ganglia system

Learning the value of environmental stimuli from reward experience allows animals to make advantageous choices. Existing biological accounts of reinforcement learning (RL) often assume that this value is represented as a single, motor-system-invariant neural signal. Here we recorded neuronal activity across eight nodes of the macaque cortico-basal ganglia system — from limbic to neocortical regions — while monkeys learned stimulus-reward associations using either saccades or reaches as the required motor response. The geometry of population activity revealed largely distinct value-coding dimensions for saccades and reaches, including in limbic regions typically associated with motor-system-invariant value coding. Consequently, value information was substantially reduced when read out across motor systems. These results provide circuit-wide evidence that challenges existing neural implementations of RL. They link biological accounts of value learning to embodied frameworks in cognitive science and artificial intelligence, in which behavior is grounded in an agent’s physical structure rather than abstracted from it. ### Competing Interest Statement The authors have declared no competing interest. Custom code used to generate the results reported in this study is publicly available at <https://github.com/GiarroccoFranco/Cortico-BasalGanglia>. The data supporting the findings of this study will be made publicly available in a suitable repository upon publication. Prior to publication, the data are available from the corresponding authors upon request. NIH, ZIAMH002928

doi.org

Andrew Pruszynski@andpru.bsky.social · 2w ago

We're hiring! Postdoc position to study the neural control of reaching using high-density multi-area electrophysiology. 5 years of funding, great collaborative environment. Please share with anyone who may be interested. For details, see: docs.google.com/document/d/1...

Pruszynski Postdoc 2026

Postdoctoral Researcher, Control Policies in the Primate Motor Circuit Pruszynski Lab @ Sensorimotor Superlab​ The Pruszynski Laboratory at Western University is seeking a postdoctoral researcher to j...

docs.google.com

Sam McDougle@actlab.bsky.social · 3w ago

The cerebellum plays a role in motor learning and reinforcement learning. But does cerebellar learning generalize to all sorts of tasks? Here we test strong prediction: that cerebellar activity tracks passively learned sensory-sensory associations (statistical learning). See below for the answer!

bioRxiv Neuroscience@biorxiv-neursci.bsky.social · 3w ago

Unsupervised nonmotor learning in the human cerebellum https://www.biorxiv.org/content/10.64898/2026.07.22.740142v1

Irene Echeverria-Altuna@irenetxeberria.bsky.social · 4w ago

Interested in timing, motor control, attention, working memory and/or stuttering? ⌛️ Curious to see how we try to bring these together in one study? 🧐 Check out our most recent, hot-off-the-press manuscript, born out of fun cross-field and cross-lab discussions ✨ Very excited to see this out ☀️🍾

Brain and Cognition Lab@brognition.bsky.social · 4w ago

🧵 New paper led by @irenetxeberria.bsky.social in press at Current Biology! A collaborative effort between the Brain and Cognition Lab and the Brain, Speech & Language Lab ⭐ Does the temporal organisation of action selection differ in stuttering? www.sciencedirect.com/science/arti... A thread 👇

Jordan Uhl@jordanuhl.com · last mo.

This isn’t even a case of Argentina being overrated, they’re not. It’s a matter of Cabo Verde being underestimated. Really incredible cup for them.

Sam McDougle@actlab.bsky.social · last mo.

Our cerebellum+RL paper is now out in the Journal of Neuroscience! "The Human Cerebellum Encodes Temporally Sensitive Reinforcement Learning Signals" @sfnjournals.bsky.social @sfn.org www.jneurosci.org/content/46/2...

The Human Cerebellum Encodes Temporally Sensitive Reinforcement Learning Signals

In addition to supervised motor learning, the cerebellum also supports nonmotor forms of learning, including reinforcement learning (RL). Recent studies in animal models have identified core RL signal...

jneurosci.org

Sam McDougle@actlab.bsky.social · last mo.

New preprint, led by Naser Al-Fawakhiri w/ Vik Chib, showing that the value of different movement goals affects motor adaptation. We think the results reflect a novel "instrumental-motor transfer" effect (à la Pavlovian-Instrumental transfer). Feedback welcome! www.biorxiv.org/content/10.6...

Instrumental-Motor Transfer: The Relative Value of Competing Movement Goals Modulates Implicit Motor Learning

Multiple learning signals can shape motor output, including reward and punishment (via value-based reinforcement learning) and sensorimotor error (via motor adaptation). However, it is unclear if acti...

biorxiv.org