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
Today I received a note from a grad student who lives in Tehran. Her note gives you firsthand experience of what it’s like to live in a city that is being bombed, and what it’s like to be young and feel despair about your future. rezashadmehr.blogspot.com/2026/03/hope...
Hopeless in Tehran
Essays on neuroscience
rezashadmehr.blogspot.com
80% of the neurons in our brain are in the cerebellum, and most of those are granule cells. What are these cells doing and why do we need so many of them? David DiGregorio will explain. The talks are open to all (contact me for link). Recorded talks: www.youtube.com/@shadmehrlab
NeuroBridges brings together students from the countries of the middle east to learn about the brain, and each other. Applications are now open. neurobridges.net/upcoming
Mark Goldman will present computational models of interacting cortical and nuclear plasticity and propose a metaplasticity mechanism that adaptively tunes spike-timing-dependent plasticity at the parallel fiber–Purkinje cell synapse. This is a zoom talk: all are welcome
Citing reduced federal funding, Johns Hopkins is exploring new low cost student housing.
Aleksandr Solzhenitsyn: “One should never direct people towards happiness, because happiness is an idol of the marketplace. One should direct them towards mutual affection...only human beings can feel affection for each other, and this is the highest achievement they can aspire to.”
Autism is a disorder that particularly affects the cerebellum. Synaptic protein abnormalities appear to underlie disrupted development, potentially resulting in cognitive symptoms. The recorded talks are available here: www.youtube.com/@shadmehrlab...
Neurobridges is a summer school that brings together students from the middle east, teaching them about synapses and circuits, but hoping to build understanding. Here is a little essay about some of the conversations that took place in 2025. rezashadmehr.blogspot.com/2026/01/neur...
The fastest inhibitory connection in the brain appears to be via a basket of axons electrically acting to inhibit Purkinje cells. The seminars are open to all (please contact me for link).
Happy New Year, everyone! Excited to share that our paper, “Goal uncertainty attenuates sensorimotor adaptation,” is now published in the Journal of Neurophysiology. Huge thanks to our collaborators—Sritej, Bobby, and Reza @rezashadmehr.bsky.social. Paper: tinyurl.com/yyfast5m
Goal uncertainty attenuates sensorimotor adaptation | Journal of Neurophysiology | American Physiological Society
Implicit sensorimotor adaptation—the automatic correction of movement errors—is driven by a perceptual prediction error, the mismatch between the perceived movement outcome and its intended goal. Alth...
tinyurl.com
Jonathan Tsay@tsay.bsky.social · last yr.New preprint with Sritej, rezashadmehr.bsky.social, and Roberta Klatzky now on biorxivpreprint.bsky.social! Motor adaptation—our ability to correct errors using feedback—is attenuated in a Bayes-optimal manner when goals are uncertain. Welcome any and all feedback! tinyurl.com/y9kjcfzj
My group of explorers, aiming to chart the cerebellum in 2026.
Are you interested in a MSc/PhD in human sensorimotor neuroscience? Learn to design experiments, analyze data, read & write papers, present at conferences, & work with a vibrant group of students & faculty in a world-class research environment. #neuroskyence #psychscisky gribblelab.org/join.html
Paul Gribble PhD
gribblelab.org
Jörn Diedrichsen@diedrichsenjorn.bsky.social · 9mo agoThe Sensorimotor Superlab with @gribblelab.org and @andpru.bsky.social is a unique place to work and learn. We are now accepting MSc and PhD applications for Fall 2026. Join our awesome team at Western University... For application instructions see diedrichsenlab.org and gribblelab.org/join.html!
Monogamy appears to coincide with the rise of cooperative society. But how monogamous are humans? DNA analysis suggests that humans are more monogamous than many other mammals, but unlike others, we live in groups in which multiple male-female pairs are monogamous and breed. tinyurl.com/mryrnufc
Human monogamy in mammalian context
Abstract. Monogamy has been argued to have played an important role in human evolution and, across animals more generally, evolutionary transitions to high
tinyurl.com
We tend to think of neurons as either excitatory or inhibitory, but some neurons chemically inhibit their downstream targets while electrically exciting their neighbors. What is gained by having an inhibitory neuron excite its neighbor? www.biorxiv.org/content/10.6...
Some forms of episodic ataxia are caused by mutations in the gene that encodes a calcium channel. Currently, no medications exist to treat it. Heather Snell presents new results on a potential therapeutic target for episodic ataxia. The seminars are open to all (contact me for zoom link).
A study finds that cats meow harder to greet their male caregivers than female. Females are more verbally interactive, more skilled at interpreting cat meows. Apparently males require more meows to notice and respond to the needs of their cats. onlinelibrary.wiley.com/doi/10.1111/...
Tenure track position in motor control at Northeastern University northeastern.wd1.myworkdayjobs.com/careers/job/...
Open Rank (Professor, Associate or Assistant) AI, Sensors, and Human Movement
About the Opportunity About Northeastern Founded in 1898, Northeastern is a global research university and the recognized leader in experience-driven lifelong learning. Our world-renowned experiential...
northeastern.wd1.myworkdayjobs.com
Shadows of our lab mates as the sun sets over San Diego and SFN comes to an end.
Our intelligence and cognitive abilities are perhaps due to an expansion of our cerebral cortex. But surprisingly, compared to highly intelligent birds, primates have many more neurons in their cerebellum as compared to the cerebral cortex. doi.org/10.1073/pnas...
The bird branch of evolution separated from mammals hundreds of millions of years ago. Yet, their cerebellum has the same structure as ours, including the zebrin bands. Here is the cerebellum of the zebra finch and the most amazing flyer of them all, the hummingbird. doi.org/10.1159/0005...
Birds are both intelligent and incredibly agile, yet they are quite small. How do they achieve this with their little brains? They have twice as many neurons per brain mass than mammals, including primates. www.pnas.org/doi/abs/10.1...
George Washington wrote to a Jewish congregation in Rhode Island that the United States was founded not on “toleration … as if it was by the indulgence of one class of people,” but on a government that “gives to bigotry no sanction.”
Tenure-track faculty position in motor neuroscience at Penn State. psu.wd1.myworkdayjobs.com/PSU_Academic...
Open-Rank Faculty Position in Sensorimotor Control and Rehabilitation Neuroscience
APPLICATION INSTRUCTIONS: CURRENT PENN STATE EMPLOYEE (faculty, staff, technical service, or student), please login to Workday to complete the internal application process. Please do not apply here, a...
psu.wd1.myworkdayjobs.com
I don't have much of a view from my office window, but this morning, the wind was brushing the vapor trails left by the rushing jets, leaving behind the froth of a cresting wave. If this was a superhero movie, there would be a surfer riding the waves in the sky.
Since start of 2025, as compared to the same period in 2024, Johns Hopkins has received 40% fewer federal awards, a decline of ~50% in research funding, a reduction of $500 million. University wide, international graduate student enrollment is down by 8% since last year.
The cerebellum receives a surprisingly rich amount of information regarding stimulus value via its climbing fibers. What role does this pathway play in learning to make better decisions? Haining Zhong will explain.
