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Pinned Tweet
20 Aug 2024
Excited the bulk of my PhD work is now out in @NeuroCellPress
If you're interested in how motor cortex and striatum work together for behavior take a look at the tweet print or here
tinyurl.com/M1Lesions
#neurotwitter #phdlife #neuroscience @CMU_Bio
20 Aug 2024
1/5 NEW in NEURON! We asked what forelimb M1 contributes to striatal and behavioral dynamics. Short answer: almost everything*. @Markolas11 trained mice to perform a joystick reaching task, w/ and w/out a go cue, then lesioned CFA tinyurl.com/M1Lesions
@cmuneurosci @CmuScience
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16 Nov 2025
Interested in how cortex and striatum contribute to trained vs spontaneous behavior??
If you're at #sfn25, check out @pgmid talk Sunday at 1
@SfNtweets #Neuroscience
16 Nov 2025
If you're at SfN, stop by my teeny tiny nano talk Sunday at 1:
"Neural population dynamics during naturalistic versus task-related behavior" w/
@YttriLab
@Markolas11
@adenoeagle
NANO017.01
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Mark A Nicholas retweeted
11 Nov 2025
Huh, it's been 8 months since I was on here. Better late than never. I hope this new-ish paper will challenge people to think about the interpretations of our models
STRIATUM SUPPORTS REINFORCEMENT AND NOT ACTION SELECTION (!!!)
cell.com/cell-reports/fullte…
@CmuScience @cmuneurosci
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23 Sep 2025
I started studying neuroscience back in 2012.
This week I will be defending my PhD from the @YttriLab at @CarnegieMellon
If you are interested in the Zoom option, please reach out.
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Mark A Nicholas retweeted
30 Jul 2025
Excited to share my postdoctoral work, with Ilana Witten and @scott_bolkan at @PrincetonNeuro.
TL;DR - we show that two basal ganglia pathways oppositely affect decision-making by very precise control of cortical subpopulations that encode accumulated sensory evidence.
30 Jul 2025
Striatal pathways oppositely shift cortical activity along the decision axis biorxiv.org/content/10.1101/… #biorxiv_neursci
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4 Apr 2025
Thank you so much to @BirnbaumJackie1 and @MunibHasnain for presenting their recent paper today at @CMU_Bio @cmuneurosci
Exciting approach to understand how to explain neural data and movement
nature.com/articles/s41593-0…
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Mark A Nicholas retweeted
27 Nov 2024
#JNeurosci: @andrewpapale1, @hooks_mac, et al. mapped out connections between neurons in mice that form the cellular basis of coordinated movement planning across the two hemispheres of the frontal cortex. @PittMed
jneurosci.org/lookup/DOI/10.…
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Mark A Nicholas retweeted
7 Nov 2024
The first preprint of my postdoc with @jtdudman
is now online! Here we wanted to understand the algorithms mice use when learning to forage in large environments with many potential resources. 1/n biorxiv.org/content/10.1101/…
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Mark A Nicholas retweeted
28 Oct 2024
Pls RT!! Do you study the brain and how we can make use of its signals? Come join our exciting faculty at CMU and @cmuneurosci.
As please feel free to reach out with any questions.
jobs.chronicle.com/job/37737…
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Mark A Nicholas retweeted
19 Oct 2024
26 years after Larry Swanson emphasized “the amygdala is neither a structural or functional unit” we used sn-RNAseq to answer the question:
“What is the [primate] amygdala?”
Check out the preprint 👇
biorxiv.org/content/10.1101/…
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Mark A Nicholas retweeted
16 Oct 2024
Neuro Robotics at @cmuneurosci!
Who wants to come join our amazing community at CMU?
@SCSatCMU @CMUEngineering @CmuScience @CMU_DietrichHSS @CMU_Robotics @CMU_ECE @CMU_Bio @cmualumnihouse @NeuroMechLabX @CMUGroverLab @YttriLab @xaqlab
Please share!
ALT Job ad for tenure-track position in CMU's Neuroscience Institute in the area of NeuroRobotics. Asst or Assoc level. Apply at https://apply.interfolio.com/157182
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9 Oct 2024
Hey if you are still around #Sfn24 this afternoon and interested in cell type-specific cortex and striatum concurrent recordings during trial and error learning, come check out our work
@YttriLab @SfNtweets #sfn2024
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Mark A Nicholas retweeted
24 Sep 2024
I am glad to share our @BrunoAverbeck @rbartolo_phd recent work published in @NeuroCellPress. We examined the neural mechanisms involved in learning from the gains and losses of symbolic reinforcers in the ventral frontostriatal circuitry. 🧠authors.elsevier.com/a/1jpyf…
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Mark A Nicholas retweeted
13 Sep 2024
When you fail to perform at your best right when it matters the most, what's going on in your brain? We can now provide an explanation: Exceptionally high stakes interfere with motor preparation. We can see this in motor cortex. Next up: finding out why.
sciencedirect.com/science/ar…
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Mark A Nicholas retweeted
13 Sep 2024
After some lovely updates thanks to reviewer/editor feedback, this work is now published in Neuron!
cell.com/article/S0896627324…
We find monotonic reward signals in M1/PMd, and interactions of reward value with neural reach signals that correlate with an inverted-U in performance
17 Apr 2023
Excited to announce “A neural basis of choking under pressure” is up on biorxiv, where we look at motor cortical population correlates of reward-mediated performance in primates.
biorxiv.org/cgi/content/shor…
Summary in thread below (1/11)
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Mark A Nicholas retweeted
11 Sep 2024
Hello all! Please give this a read - and amplify! #SimCo2024 #ThankAMonkey #EndSufferingThruScience
jneurosci.org/content/44/37/…
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Mark A Nicholas retweeted
4 Sep 2024
Researchers in @YttriLab discovered how the motor cortex and striatum work together to create movement.
cmu.edu/mcs/news-events/2024…
ALT A cross section rat brain with the primary motor cortex removed.
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Mark A Nicholas retweeted
27 May 2024
*New preprint* - We (Tim Verstynen, Jonathan Rubin and I) show how cortico-basalganglia-thalamic networks can maximize reward rate 🙂 - biorxiv.org/content/10.1101/…
22 May 2024
How cortico-basal ganglia-thalamic subnetworks can shift decision policies to maximize reward rate biorxiv.org/cgi/content/shor… #biorxiv_neursci
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6 Mar 2024
Yes there was a time in lab where I did have to care for slime molds...
6 Mar 2024
When you ask your boss @YttriLab to come on your podcast to discuss neurobehavior, and all he wants to talk about are octopuses and slime molds...
Kidding. Mostly.
Eric and I chat about how brains do behaviors and why that's not a simple question.
braininspired.co/podcast/185…
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Mark A Nicholas retweeted
21 Feb 2024
1/5 NATURE METHODS TWEETPRINT! Do you have a specific, nuanced, or rare set of behaviors you want to extract from video/pose estimation data? Want to extract those better and with a tenth of the training?
Regardless of species, A-SOiD is here to help
nature.com/articles/s41592-0…
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