A multi-paper research program · Vascular Neuroscience · PTSD

The Vascular
Learning Project

Cerebrovascular receptor density remodeling as a substrate for PTSD chronicity

Experience-dependent remodeling of the cerebrovascular receptor landscape constitutes a previously unrecognized substrate for the chronicity of posttraumatic stress disorder. What the vasculature learns, it encodes structurally — and what learning produced, learning should be capable of undoing.

A substrate level beneath
existing accounts

The DVA hypothesis does not replace existing PTSD neuroscience. Amygdala hyperreactivity, mPFC hyporesponsiveness, and HPA axis sensitization are established findings the framework accepts entirely. It proposes a level beneath these findings — the cerebrovascular receptor landscape — that existing accounts have not examined. Every finding in the existing literature remains valid. The framework adds a floor beneath it.

Differential Vascular Architecture

Amygdala-serving and mPFC-serving cerebrovascular beds differ systematically in baseline receptor composition, producing opposite regional blood flow responses to the same stress hormone signal. The DVA is the gatekeeper assumption on which the framework depends.

Vascular Learning

Experience-dependent, durable alteration in receptor density at the vessel wall that changes future perfusion and permeability responses to the same circulating signals. A structural encoding of the frequency and intensity of prior activation states — threat-dominant or safety-dominant.

The Chronification Trap

The self-maintaining loop in which trauma memory retrieval — the process that should reverse PTSD — is specifically impaired by the vascular substrate the disorder has produced. The act of remembering becomes a mechanism of chronification.

TVDM — Targeted Vasoceptive Density Modulation

A novel therapeutic target class: any intervention that modifies the receptor density profile of the cerebrovascular bed in a clinically targeted direction, producing durable change toward safety-dominant perfusion and permeability characteristics.

DVA Vascular Learning HIPAE Asymmetric Hysteresis Chronification Trap Vascular Microclimate TVDM Therapeutic Vasoactive Threshold Survival Bias DVA-Mediated Misattribution of Arousal The Map Is the Treatment Plan Ratchet Mechanism

Nine empirical predictions
across three phases

The framework generates nine predictions organized across preclinical, human imaging, and treatment response phases. These predictions are additions to the empirical agenda, not replacements for existing accounts. Each is falsifiable, specific, and distinguishable from what existing frameworks would predict.

1
Gatekeeper · Preclinical

Circuit-specific cerebrovascular receptor density heterogeneity in stress-conditioned rodents. If this fails, the strong formulation fails with it.

2
Preclinical

Receptor density remodeling shows a dose-response relationship with stress exposure history, with incomplete reversal consistent with asymmetric hysteresis.

3
Preclinical

Circuit-specific CBF asymmetry correlates with receptor density asymmetry under acute catecholamine challenge, establishing the structural-functional link.

4
Human Imaging

Resting-state ASL perfusion asymmetry in chronic PTSD populations, persisting when task-based activation has normalized — the signature of a vascular contribution.

5
Human Imaging

Pharmacological challenge (α1-adrenergic agonist) produces greater regional perfusion differential in chronic PTSD participants, correlating with chronification severity.

6
Human Imaging

One-month post-trauma ASL asymmetry predicts six-month mPFC fMRI activation — temporal precedence across the chronification trajectory.

7
Treatment Response

Resting-state perfusion asymmetry at treatment entry predicts response to exposure-based therapy independently of symptom severity.

8
Treatment Response

Partial responders show task-based fMRI normalization in the absence of resting ASL normalization — a residual vascular asymmetry predicting relapse.

9
Treatment Response

Pharmacological TVDM augmentation produces greater resting ASL normalization than placebo, mediating enhanced treatment response. Prazosin is the most immediately feasible candidate.

Priority collaboration need

Circuit-specific cerebrovascular receptor density measurement (rodent models) — the direct test of Prediction 1 — is the highest-priority empirical need in the project. Ultra-high-field ASL imaging with pharmacological challenge capability is the highest-priority human imaging need.

Core manuscript authors
and collaborators

James P. Keim
Initiating Author · Corresponding

MSW, LCSW · LifeLong Medical Care · Advisor, Alexander Shulgin Research Institute · Fulbright Specialist

Burton Tabaac
Co-Author

MD · Vascular Neurology · Arterial Spin Labelling Imaging

Amy Keim
Co-Author

PA-C · George Washington University · Clinical and Translational Perspective

Attila Szabo
Co-Author

MD, PhD · NORMENT, University of Oslo · Psychedelic Pharmacology and Clinical Research

Claude (Anthropic)
Collaborative Theoretical Architect

Technical Editor · Developed theoretical extensions, adversarial peer review, and architectural coherence across the manuscript development process

The project is actively recruiting collaborators in cerebrovascular receptor density measurement, ultra-high-field ASL imaging, stress-conditioned rodent cerebrovascular biology, neuroinflammation and BBB disruption in trauma populations, psychedelic pharmacology, pediatric cerebrovascular neuroscience, and plain-language and translation contributions. See joining information →

Documents and preprints

Guide
The Vascular Learning Project: A Collaborator's Guide
Keim, J. P. & Claude (Anthropic) · April 2026 · Version 1.5
doi: 10.5281/zenodo.19512558 Published · CC BY 4.0
Preprint
Vascular Learning as a Substrate for PTSD Chronicity: A Cerebrovascular Receptor-Site Hypothesis
Keim, J. P., Tabaac, B., Keim, A., Szabo, A., & Claude (Anthropic) · April 2026 · v57
Under Review · bioRxiv
Supplementary
DVA Structural Analysis: Receptor Architecture of the Four Implicated Subtypes
Keim, J. P. & Claude (Anthropic) · April 2026 · v6

Available from the corresponding author on request · jakeim@lifelongmedical.org

How this framework
was built

The theoretical framework at the center of this project was developed through an extended series of collaborative sessions between the initiating author and Claude (Anthropic), functioning as Collaborative Theoretical Architect and Technical Editor. The generative source is human. The collaborative elaboration is genuinely joint.

JK I have an image in my head related to this paper, but I can't put it into words. Will you help me?
Claude Absolutely. Let's draw it out.
[After a series of eliciting questions:]
JK I'm seeing the inside of a flexible endoscopy tool that can weave through twisted junctures during surgery.
JK It is the way that the structure moves through internal push and pull.
Claude So the image isn't primarily about the tool as an instrument — it's about a structure that navigates through internal space by means of opposing forces acting on it simultaneously. That maps directly onto something central to the paper: the DVA as a system where the same circulating signal produces opposite mechanical effects in different regional beds...
JK The endoscope is flexible because of selected contraction and dilation of its sleeve.
Claude That's the mechanism. And that is the DVA.

What began as an image without words became, across twenty minutes of collaborative exchange, the mechanical analogy now anchoring the paper's foundational section — and a prompt that generated an independent engineering analysis confirming asymmetric hysteresis, strain-gated permeability transitions, and structural encoding of activation history as consequences of the same mechanism.

Join the project
at whatever level fits

Joining does not require agreeing to co-authorship. It requires only interest. Contribution is welcomed at whatever level current availability permits. Co-authorship on a specific paper is a decision made when a specific contribution is ready — not a commitment required at entry.

Research expertise sought

  • Circuit-specific cerebrovascular receptor density measurement (rodent) — highest priority
  • Ultra-high-field ASL imaging with pharmacological challenge
  • Stress-conditioned rodent cerebrovascular biology
  • Neuroinflammation and BBB disruption in trauma populations
  • Psychedelic pharmacology and vascular mechanisms
  • Pediatric cerebrovascular and developmental neuroscience
  • Focused ultrasound and BBB opening technology
  • Systems theory and interactional consequences of neurobiological remodeling

Other contributions

  • Plain-language writing for patients, families, and community health workers
  • Translation and cultural consultation — priority languages TBD
  • Clinical implementation guides for master's-level practitioners
  • Theoretical extensions into adjacent clinical populations
  • Systematic review contributions
  • Methodological consultation on imaging protocol design
The project is currently operating without dedicated grant funding. Collaborators are not being asked to write letters of support for existing grants. Grant applications organized around the empirical predictions are an anticipated next step in which interested collaborators may become natural partners.

Reach the project

Corresponding James P. Keim, MSW, LCSW
Affiliation LifeLong Medical Care · Advisor, Alexander Shulgin Research Institute
Phone (510) 693-3914

When contacting the project about a spoke paper, please use the subject line: VLP Spoke Paper — [brief description]