Carl (CJ) Litif, Ph.D.

Drug‐Related Engrams and Their Role in the Persistence and Recurrence of Drug‐Related Behaviors Memory is a cornerstone of human behavior, and addiction offers a compelling model of its persistence and plasticity. The scope of engram research has rapidly expanded to include addiction-related ph....

First lab paper out today! Student authors: Mikayla Cutler and Abhi Thati 🎉🤩

Hippocampus | Neuroscience Journal | Wiley Online Library onlinelibrary.wiley.com/doi/10.1002/...

Long post ahead! I am very excited to be recruiting 1 to 2 #PhD students during this upcoming application cycle for Fall 2026 admission! The Clinical Psychology PhD program at The University of New Mexico (UNM) is absolutely stellar and accredited by both #APA and #PCSAS (Clinical Science model). 1/

So basically all the science that helps humanity…. 🤦‍♂️

A diagram showing dozens of brain regions densely interconnected by complicated loops

I think about this diagram a lot. This is a *simplified* schematic of *some of* the brain regions and circuits involved in behavioral control. (From: www.sciencedirect.com/science/arti...)

#eNeuro: @mattjwanat.bsky.social‬ et al. show that the cue-evoked dopamine response in rats signals the duration of the trace period between cue and reward, and relates to the response latency.
https://doi.org/10.1523/ENEURO.0016-25.2025

Models as Prediction Machines: How to Convert Confusing Coefficients into Clear Quantities Abstract Psychological researchers usually make sense of regression models by interpreting coefficient estimates directly. This works well enough for simple linear models, but is more challenging for more complex models with, for example, categorical variables, interactions, non-linearities, and hierarchical structures. Here, we introduce an alternative approach to making sense of statistical models. The central idea is to abstract away from the mechanics of estimation, and to treat models as “counterfactual prediction machines,” which are subsequently queried to estimate quantities and conduct tests that matter substantively. This workflow is model-agnostic; it can be applied in a consistent fashion to draw causal or descriptive inference from a wide range of models. We illustrate how to implement this workflow with the marginaleffects package, which supports over 100 different classes of models in R and Python, and present two worked examples. These examples show how the workflow can be applied across designs (e.g., observational study, randomized experiment) to answer different research questions (e.g., associations, causal effects, effect heterogeneity) while facing various challenges (e.g., controlling for confounders in a flexible manner, modelling ordinal outcomes, and interpreting non-linear models).

Figure illustrating model predictions. On the X-axis the predictor, annual gross income in Euro. On the Y-axis the outcome, predicted life satisfaction. A solid line marks the curve of predictions on which individual data points are marked as model-implied outcomes at incomes of interest. Comparing two such predictions gives us a comparison. We can also fit a tangent to the line of predictions, which illustrates the slope at any given point of the curve.

A figure illustrating various ways to include age as a predictor in a model. On the x-axis age (predictor), on the y-axis the outcome (model-implied importance of friends, including confidence intervals). Illustrated are 1. age as a categorical predictor, resultings in the predictions bouncing around a lot with wide confidence intervals 2. age as a linear predictor, which forces a straight line through the data points that has a very tight confidence band and 3. age splines, which lies somewhere in between as it smoothly follows the data but has more uncertainty than the straight line.

Ever stared at a table of regression coefficients & wondered what you're doing with your life?

Very excited to share this gentle introduction to another way of making sense of statistical models (w @vincentab.bsky.social)
Preprint: doi.org/10.31234/osf...
Website: j-rohrer.github.io/marginal-psy...

Very excited to share this major update to our paper delineating VTA GABA neuron encoding of valence and decision conflict. Studies led by the amazing @margestelzner.bsky.social. We leaned in here, taking the opportunity to add a lot of cool new data. www.biorxiv.org/content/10.1...

Congrats to Sven Bervoets and co-authors for our paper on fly Arc now out in @currentbiology.bsky.social !! This was an awesome collaboration with @thecaronlab.bsky.social’s lab @utah.edu

authors.elsevier.com/c/1lZlk3QW8S...

The many benefits of the LPU A Daniel Sarewitz wrote an opinion piece in Nature awhile back to argue that the pressure to publish regularly has driven down the quality of science. Moreover, he claims to have identified ……

Why publishing early and often advances science faster than complete story bullshit.

This is related to replication and generalization.

From the Archive: The many benefits of the LPU drugmonkey.wordpress.com/2016/06/29/t...

Individual differences in decision-making shape how mesolimbic dopamine regulates choice confidence and change-of-mind - Nature Neuroscience Differences in neuroeconomic decision-making influence nucleus accumbens dopamine dynamics and reflect choice confidence during evaluation, as well as past and future value during re-evaluation, which...

Dopamine dynamics in the nucleus accumbens core reflected decision confidence during evaluation of decisions in an economic foraging task in mice, as well as both past and future value during re-evaluation and change-of-mind

@perothwell.bsky.social

www.nature.com/articles/s41...

An integrated single-nucleus and spatial transcriptomics atlas reveals the molecular landscape of the human hippocampus - Nature Neuroscience The topographical organization of cells in the hippocampus reflects its ability to regulate mood and cognition. Here the authors generate a spatially resolved gene expression map in the human hippocam...

Excited to share this huge team effort collaboration supervised by Stephanie Page in Translational Neuroscience @lieberinstitute.bsky.social and @stephaniehicks.bsky.social @jhubiostat.bsky.social to generate a spatio-molecular resource of the hippocampus in human 🧠

www.nature.com/articles/s41...

The field of neuroscience views the goal of human genetics as "finding genes". This is an outdated view. In whole genome studies of rare variants, finding genes is the easy part. The more interesting and important goal is to map out the causal pathway from genes to brain function to cognitive traits

Good stuff from Alex. I touch on some of these themes here as well, from the perspective of an applied statistician (plus a few more refs on the topic).

statsepi.substack.com/p/statistica... (ICYMI)

Dr. Sudie Back - Prolonged Exposure for Substance Use Disorder and PTSD Podcast Episode · The Addiction Psychologist · 07/14/2025 · 1h 17m

Newest episode of The Addiction Psychologist (@addpsychpodcast.bsky.social) just dropped. In this episode, Dr. Sudie Back discusses Prolonged Exposure for Co-Occurring Substance Use Disorder and PTSD (COPE).

podcasts.apple.com/us/podcast/t...

Long-Term Effects of Adolescent 5F-MDMB-PICA Intravenous self-administration: Neurobehavioral Consequences and medial Prefrontal Cortex Dysfunction in Adult Mice https://www.biorxiv.org/content/10.1101/2025.06.26.661592v1

Winter Conference on Brain Research January 24th to 29th 2026 Big Sky Montana!

Submissions for #WCBR2026 open today! Please go to www.winterbrain.org Big Sky is my absolute favorite venue for this meeting. The science is top notch, the people are great, the meaning is inclusive, and I learned to ski as a 35 year old! Please repost!

Modulation of Dopamine Neurons Alters Behavior and Event Encoding in the Nucleus Accumbens during Pavlovian Conditioning When a cue is located away from its associated reward, some animals will learn to approach the site of reward (goal-tracking behavior) while others will approach the cue (sign-tracking behavior). The ...

We are delighted to have the cover article in J Neurosci this week! Briefly: inhibition of DA neurons at reward blocks the acquisition of sign tracking; stimulation (or bigger reward) doesn't alter it, but *stopping* stimulation halts acquisition in its tracks. www.jneurosci.org/content/45/2...

Pict of article titled Adolescent and young adult access to opioid use disorder care

📣New paper out in Pediatrics about Adolescent & Young Adult OUD Care Access, by part of our UW team💕, & co-first-author, Dr. Alexis Ball!

📝Documenting part of what we already know in practice:

real care options & honest conversations @ drug use matter a lot.

publications.aap.org/pediatrics/a...

Judge Rejects Trump’s ‘Appalling’ NIH LGBTQ, Race Grant Cuts (1) The Trump administration’s cuts to scientific research grants for focusing on gender and diversity, equity and inclusion are illegal and vacated, a federal judge in Massachusetts ruled from the bench ...

news.bloomberglaw.com/health-law-a...

So are they going to reinstate those that were cut? 👀

Today, my NIH colleagues and I did something scary but really important. We spoke up about egregious harms we are seeing happen to research participants and public health through thoughtless and politicized policies at NIH. 🧵1/3

apnews.com/article/nih-...

OPINION: Federal cuts put addiction treatment and recovery at risk I vividly remember growing up and my grandmother warning me to be careful with alcohol — because addiction “runs in our family.” She wasn’t wrong. For generations, both sides of

New op-ed out in the Albuquerque Journal. I share about the importance of federal substance use and addiction funding for families like mine.

www.abqjournal.com/opinion/arti...

and in case you hit a paywall: unmm-my.sharepoint.com/:b:/g/person...

Why use a $20k+ centrifuge to spin your qpcr plate when you have $20 salad spinners 🤣

Newest version of Cellpose can spot cell boundaries even in cloudy conditions Picking out individual cells in distorted microscopy images is now as easy as clicking a button. A new version of Cellpose – the popular tool that maps the boundaries of diverse cells in microscopy

🖱️ Picking out individual cells in distorted microscopy images is now as easy as clicking a button, thanks to Cellpose3: www.janelia.org/news/newest-...

Motor learning refines thalamic influence on motor cortex - Nature Imaging and optogenetics in mice provide insight into the interplay between the primary motor cortex and the motor thalamus during learning, showing that thalamic inputs have a key role in the executi...

Our paper is out in Nature.

By examining various inputs to the motor cortex during learning, we found that thalamic inputs learn to activate the cortical neurons encoding the movement being learned.

Tour de force by Assaf in collab with Felix and Marcus. Congrats!

www.nature.com/articles/s41...

Sex differences are often claimed based on faulty comparison of statistical significance status rather than direct comparison.

That's the upshot of an amazing talk I got to hear this week from Donna Maney @ Emory based on this paper & others: elifesciences.org/articles/70817

#stats #neuroskyence

Circulating Immune and Endocrine Markers in Currently Drinking and Abstinent Individuals With Alcohol Use Disorder and Controls Circulating concentrations of BDNF, GLP-1 and IL-8 were altered only in abstinent individuals with AUD, likely reflecting greater disease burden and comorbidities compared to current drinkers.

My first post doc data paper!!

onlinelibrary.wiley.com/doi/10.1111/...

informative thread here

Me to my brain organoid in an operant chamber after animal research is defunded

Molecular and genetic mechanisms of plasticity in addiction Drugs of abuse result in well-characterized changes in synapse function and number in brain reward regions such as the nucleus accumbens. However, rec…

New review from Kasey Brida on transcriptional & molecular mechanisms in drug-induced plasticity. Here we focused on mechanisms that determine which neurons are activated by drugs, and dynamic transcriptional cascades that facilitate plasticity in these cells.
www.sciencedirect.com/science/arti...