Alex Huk

[Alex Huk @realAlexHuk]

@UCLANeuroTheme @UCLA Zili is a master of using very simple (elegant) visual displays to help us to think clearly about how the eye and brain make informed guesses about what is out there in the world.

[Alex Huk @realAlexHuk]

My lab at UCLA has an open spot for a postdoc to do 2P and Neuropixels in awake behaving marmosets. NHP background not required; imaging expertise strongly preferred. Email me at alexhuk at ucla dot edu for more info.

[Alex Huk @realAlexHuk]

@latimerkw @hcratigan I'll work up an invoice for that one paper, plus interest. Oh and let me know the authors so I can see how big the penalty should be :)

[Alex Huk @realAlexHuk]

@anne_churchland @CoryMillerMarmo @J_D_Crawford @mtraghavan @MIcheleABasso1 I'll work up a proposal

[Alex Huk @realAlexHuk]

@julie_charlton_ DLC is for the next wave of the project, to pick apart running from non-running movements/fidgets from general arousal (with, say, pupil as a metric for that). The version of the gain modulator model we got from Dan Butts and Jake is very applicable to that dissection.

[Alex Huk @realAlexHuk]

@julie_charlton_ Yes we dialed in the friction to make the animals comfortable-- not too fast and not too slow. There are a lot of measures of arousal and exertion that we want to unpack...

[Alex Huk @realAlexHuk]

@julie_charlton_ I forgot to mention, I think stride length on the treadmill is much shorter than the napkin calculation-- that # was likely from the "galloping" that they are capable of but which you won't see on a treadmill despite them seeming to be really booking when you watch them

[Alex Huk @realAlexHuk]

@julie_charlton_ (A subtlety: some of our analyses correlate a brain metric with running speed, as opposed to just binarizing by a threshold; we don't always show this in the ms but similar answers either way)

[Alex Huk @realAlexHuk]

@DavidAMcCormick @jcbyts Thanks! I'll see you and raise you that both running and not-running are likely different, cross species. For starters, we just speak to the objective reality that is running. But unpacking the underlying behavioral states and uses of vision for action is where we are going...

[Alex Huk @realAlexHuk]

We sought to test whether running modulates primate V1 like it does in mouse, but ended up fascinated by shared gain modulations and their relation to behavior. We think this lays groundwork for extracting general cross-species principles https://t.co/NGPmtNWzxs

[Alex Huk @realAlexHuk]

@julie_charlton_ That aside, I see your main point: running likely means something rather different with respect to mouse and marmoset; whether that's a quantitative or categorical distinction is, well, something that will take some very fun experiments to get at.

[Alex Huk @realAlexHuk]

@julie_charlton_ Fun stuff. Those are real world units, so speed on ground is as in the figure; speed of scurrying is however surely quite different, as those two species have very different bodies and running styles...

[Alex Huk @realAlexHuk]

@jcbyts @IntlBrainLab @AllenInstitute Strong agrees, both on how this was not easy to translate to NHP (again, super job by @j_liska on that!) and how building shared, large-scale, cross-species infrastructure could be really good.

[Anne Churchland @anne_churchland]

1/2 When neural responses differ across species, folks lose hope for shared computations. Should they? This paper explains how 1 mechanism-- trial-to-trial fluctuations of shared gain-- explains mouse & NHP V1, w/ variations in correlation sign & magnitude https://t.co/PseXCJmOie

[Alex Huk @realAlexHuk]

@_stah Thanks @_stah !

[Alex Huk @realAlexHuk]

@courellis That is likely the next paper! Saccades are a worthy deep dive in both species .... stay tuned; that analysis needs a finer-time-scale analysis that is within reach but not in this first manuscript. (That said I do not think saccades are driving the effects we see).

[Alex Huk @realAlexHuk]

And much gratitude to @AllenInstitute neuro folks for lovely mouse data and making it publicly accessible

[Alex Huk @realAlexHuk]

Was a great team effort, huge credit to @jcbyts and @NeuralCodeUMD on the analysis side, and @j_liska and @Dec_Rowley getting great data in a new rig

[Alex Huk @realAlexHuk]

@MingsChirps Thanks; interesting Qs! We are getting more Neuropixels data to answer the layer question. Will look into waveforms, although I've not been super compelled by that distinction in our hands and hope to follow up with more direct imaging measures...