Maithe Arruda Carvalho

Identification of an engram ensemble mediating memory forgetting in the dentate gyrus Hu et al. show that the dentate gyrus engram comprises two neuronal ensembles: one supports remembering, and the other promotes forgetting. By shifting the balance between these ensembles via Rac1 sig...

Identification of an engram ensemble mediating memory forgetting in the dentate gyrus
www.cell.com/neuron/abstr...

13% success rates at #CIHR, is a really 87% fail rate for>4000 scientists. At a time when 🇨🇦 is investing millions to recruit more scientist into a broken funding environment. 🇨🇦, U need a strong science foundation 2 attract success. #CIHR, fix your science foundation, it is eroding in real time

#JNeurosci: Johantges et al. used mice to study excitatory and inhibitory synaptic connections in the CA1 region, creating a circuit map with cell-type resolution that will guide future research on how the hippocampus supports learning and memory.
https://doi.org/10.1523/JNEUROSCI.1102-25.2025

Let’s be clear, no funder can absorb a 50% increase in application over a period of two years without a significant increase in resources. It is unsustainable and will trigger significant policy changes, which will cause significant challenges. This needs everyone working together.

We were on the cusp of changing medicine forever. Curing things that had no cure. mRNA vaccines are revolutionary

The shingles vaccine has demonstrated in what is now a 4th replication that it results in a ~20% reduction in dementia. This is better than any drug ever designed and tested for Alzheimer’s.

This amazing woman worked so hard for science and sport in Canada. She set up the Standing Committee on Science and Research, was a powerful voice for science in parliament and after being diagnosed with two cancers continued to advocate for good. Proud to have known the Rt Hon Kirsty Duncan. RIP 💔

Save the date for the annual "Neural Circuits and Behaviour" satellite conference at the Canadian Association for Neuroscience annual meeting, cohosted by @franklandlab.bsky.social and myself on May 18, 2026. We have a great speaker lineup and will be selecting 4 trainees talks from our registrants!

Agriculture and Agri-Food Canada is closing seven of its research operations Work force will be reduced by about 665 positions, organization says, as part of government’s effort to shrink public service

Cuts to the research & scientific expertise that guard public health - in this case food safety - are very troubling in light of Canada’s weakened ability to rely on US science.

Protecting Canadians requires more, not less, in these areas.

www.theglobeandmail.com/canada/artic...

100%. I wrote about how Carney needs to strengthen Canada's regulatory capacity, esp. in food & health, as the US guts its regulatory & science capacities. Carney's cutting the public service is dangerous & plans use AI chatbots instead in govt is foolhardy. policyoptions.irpp.org/2025/12/trum...

Maturation of hippocampus-medial prefrontal cortex projections defines a pathway-specific sensitive period for cognitive flexibility Cruz-Sanchez et al. show that the maturation trajectory of ventral and intermediate hippocampus-medial prefrontal cortex connectivity displays distinct anatomical and synaptic developmental signatures...

Happy to share the latest from our lab published @cp-cellreports.bsky.social, where we delineated the synaptic maturation trajectory for vCA1 and iCA1 projections to mPFC, and pathway-specific effects of vCA1- and iCA1-mPFC juvenile inhibition on cognitive flexibility

www.cell.com/cell-reports...

A prefrontal cortex map based on single-neuron activity - Nature Neuroscience The authors mapped spontaneous and choice activity across mouse prefrontal cortex. The activity maps aligned with intrinsic connectivity rather than anatomical subregions, suggesting that connectivity...

Main postdoc study out! We can redefine prefrontal cortex regions with single-unit activity! Grateful to @carlenlab.bsky.social and @weltgeischt.bsky.social who made this crazy project real. Thanks to all co-authors, collaborators, and reviewers.
www.nature.com/articles/s41...

Registration is filling up fast!

Prefrontal neural geometry of learned cues guides motivated behaviours
www.nature.com/articles/s41...

Viral delivery of microRNA in patients with Huntington's - years of basic science at Universities, Colleges & Medical Centers make this possible. Hopeful & Exciting

I meet a lot of pregnant women at work.
A grand total of 0 (ZERO!) have been advised to get a COVID vaccine in pregnancy.
I would say the majority have bought into the misinformation that the vaccine is dangerous in pregnancy, which is the opposite of the truth.

Examining the Three‐Dimensional Spatial Architecture of Mouse Amygdala Engram Ensembles Memories are stored in a sparse population of neurons active at the time of an event, an engram ensemble, and reactivation of the engram ensemble drives memory recall. Although the amygdala is essent...

New Year, new paper from our lab. Emily Kramer used 3D light-sheet imaging and tissue clearing to examine the spatial architecture of mouse amygdala engram ensembles.

onlinelibrary.wiley.com/doi/10.1002/...

We talked about running these numbers at UM soc when it became so obvious that women TAs got more complaints for the same classes. Glad someone tested it formally.

We published some a few years ago. You can find the link to the files in the paper: www.eneuro.org/content/eneu...

The Injunction Against Bill 26 Has Been Lifted: Affirming care ban to come into effect. Despite our best efforts, today the Government of Alberta was able to bring an end to the injunction against Bill 26 on the basis of its use of the notwithstanding clause. This is a cruel and dangerous move by a government that will harm vulnerable young people. Egale Canada and Skipping Stone will not stop fighting. Together, with lawyers from McCarthy Tétrault LLP, we will be seeking a new injunction based on constitutional arguments not subject to the notwithstanding clause. To the trans youth and families in this province, know that while the Government has violently taken away your rights, they can never legislate away your transness, your beautiful existence or how deserving you are of all the beauty and happiness this world has to offer.

Heartbreakingly, despite our best efforts, today the Government of Alberta was able to bring an end to the injunction against Bill 26 on the basis of its use of the notwithstanding clause.

This is a cruel and dangerous move by a government that will harm vulnerable young people.

📣We have 2 open faculty positions for senior researchers in Neuroscience at Queen's University!

healthsci.queensu.ca/administrati...

1. a new Director for our Centre for Neuroscience Studies
2. a non-human primate NeuroAI researcher

Please share widely and reach out for questions!

Yet one more reason we cannot allow LLMs to serve as epistemic grounding is that we cannot triangulate among them the way you can among reasonable independent sources. They bullshit in the same way and end up agreeing with one other about things that are completely false.

COVID Vaccines Slashed Kids’ ER Visits by 76 Percent, Study Finds A report published by the CDC reaffirms the effectiveness of COVID vaccines at preventing severe disease in children

COVID Vaccines Slashed Kids’ ER Visits by 76 Percent, Study Finds www.scientificamerican.com/article/covi...

Highly recommend!!!

Breaking: Spain brings masks back.

Mandatory in hospitals, primary care, and long-term care—for patients, visitors, and staff.
Strong recommendation everywhere else.
Public health moving where evidence points.

Note: Really worth upgrading to respirators.
euroweeklynews.com/2025/11/28/s...

Australia just recorded zero cervical cancer cases in women under 25 for the first time since records began in 1982. The amazing result of HPV vaccination.

Join us Dec 8 with Dr. Deena Walker to learn how drugs of abuse disrupt thyroid signaling, how this alters reward pathways, and how a CNS-specific thyromimetic may reduce reward-driven behaviors.

🔗 Register: eventbrite.com/e/thyroid-ho...

#AddictionScience #SexDifferences

230,000 Deaths and the ‘Calculated Silence’ of the Medical Establishment About the COVID Inquiry The Covid Inquiry Report is a devastating critique of the medical establishment which led the UK to the worst public health disaster in a century, argues Anthony Costello

🔴230,000 Deaths and the ‘Calculated Silence’ of the Medical Establishment About the COVID Inquiry

The Covid Inquiry Report is a devastating critique of the medical establishment which led the UK to the worst public health disaster in a century, argues Anthony Costello

Seventh patient ‘cured’ of HIV: why scientists are excited A man in Germany is HIV-free after receiving stem cells that are not resistant to the virus.

A 60-year old man in Germany became the seventh person with HIV to be announced free of the virus after receiving a stem-cell transplant

go.nature.com/48C68Ib

Thalamocortical transcriptional gates coordinate memory stabilization - Nature The sequential recruitment of a thalamocortical transcriptional cascade enables memory maintenance over long timescales.

Thalamocortical transcriptional gates coordinate memory stabilization
www.nature.com/articles/s41...