About

Adam E. Cohen is a Professor of Chemistry and Chemical Biology and Physics at Harvard University, affiliated with the Departments of Chemistry and Chemical Biology and of Physics. His research focuses on understanding brain function through the development of advanced imaging tools and techniques. He has developed methods for high-resolution genetically targeted voltage imaging of neural populations in awake, behaving animals, and combines this with targeted optogenetic perturbations to investigate how neural circuits transform inputs to outputs. His current research includes studying the control of attention in cortical Layer 1 and mechanisms of plasticity in the hippocampus. Cohen's lab also works on creating new tools for probing the brain, such as techniques to increase the number of neurons that can be recorded simultaneously, all-optical tools for neural circuit mapping in vivo, and mapping the spatial structures of memories. His lab members come from diverse backgrounds including neuroscience, physics, chemistry, and molecular and cellular biology.

Research topics

• Neuroscience
• Biology
• Physics
• Psychology

Selected publications

• A dendrite-resolved, <i>in vivo</i> transfer function from spike patterns to dendritic Ca ²⁺

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-01-21

  articleOpen accessSenior authorCorresponding

  Abstract Dendrites transform local electrical activity into intracellular Ca 2+ signals that drive plasticity 1,2 , yet the voltage→Ca 2+ mapping during natural behavior remains poorly defined. Here, we measure this transfer function via simultaneous voltage and Ca 2+ imaging throughout the dendritic arbors of hippocampal CA2 pyramidal neurons in behaving mice. Dendritic Ca 2+ exhibited a hierarchical activation pattern dominated by back-propagating action potentials: simple spikes primarily drove somatic and proximal Ca 2+ , whereas complex spikes produced larger somatic Ca 2+ signals and propagated farther into distal dendrites, sometimes in a branch-selective manner. Dendrite-restricted co-activation of voltage and Ca 2+ without concurrent somatic events was rare. A biophysics-inspired model accurately predicted local Ca 2+ transients from local voltage waveforms. Our data and model provide a quantitative understanding of when – and why – dendritic Ca 2+ signals in CA2 pyramidal cells arise during behavior.

  PublisherOA PDFDOI

• Fast dendritic excitations primarily mediate back-propagation in CA1 pyramidal neurons during behavior

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-01-03 · 2 citations

  articleOpen accessSenior authorCorresponding

  Abstract Dendrites integrate synaptic inputs to trigger action potentials, and dendrites carry back-propagating action potentials (bAPs) to synapses where these signals contribute to plasticity. Despite strong evidence for a rich repertoire of nonlinear dendritic excitations, the in vivo roles of these excitations in dendritic integration and back-propagation remain uncertain. Here, we used high-speed voltage imaging through a chronically implanted microprism to map membrane potential dynamics from basal to apical dendrites of CA1 neurons in mice navigating in a virtual reality environment. Despite complex dendritic branch morphology, the dynamics were largely captured by 2 or 3 electrical compartments: basal, soma, and apical. Fast dendritic spikes almost always started from bAPs, indicating that dendritic spikes are primarily a consequence rather than a cause of somatic spiking. These fast spikes sometimes triggered slower apical dendritic plateau depolarizations, which drove complex spikes at the soma. We found that the biophysics of dendritic excitability determined the distribution of simple and complex spikes across a place field. Our results show how CA1 pyramidal neurons convert synaptic inputs to spiking outputs and suggest a primary role of dendritic nonlinearities in mediating activity-dependent plasticity.

  PublisherDOI

• DMD-patterned structured illumination for imaging brain activity

  2026-03-05

  article1st authorCorresponding
  PublisherDOI

• Mechanism of giant magnetic field effect in a red fluorescent protein

  2026-03-04

  article1st authorCorresponding

  We found that mScarlet3 fluorescence in E. coli reversibly decreased by 21% in the presence of a 60 mT magnetic field, the largest magnetic field effect (MFE) reported in any fluorescent protein. We developed a quantitative model of the giant MFE in mScarlet3. Our quantitative model of the photocycle provides a framework for the design and optimization of magnetic-field-sensitive proteins, opening possibilities in fluorescent protein-based magnetometry, magnetic imaging, and magnetogenetic control.

  PublisherDOI

• Ether lipids influence cancer cell fate by modulating iron uptake

  Nature Communications · 2026-01-27 · 1 citations

  articleOpen access

  Cancer cell fate has been widely ascribed to mutational changes within protein-coding genes associated with tumor suppressors and oncogenes. In contrast, the mechanisms through which the biophysical properties of membrane lipids influence cancer cell survival, dedifferentiation and metastasis have received little scrutiny. Here, we report that cancer cells endowed with high metastatic ability and cancer stem cell-like traits employ ether lipids to maintain low membrane tension and high membrane fluidity. Using genetic approaches and lipid reconstitution assays, we show that these ether lipid-regulated biophysical properties permit non-clathrin-mediated iron endocytosis via CD44, resulting in significant increases in intracellular redox-active iron and enhanced ferroptosis susceptibility. Using a combination of in vitro three-dimensional microvascular network systems and in vivo animal models, we show that loss of ether lipids from plasma membranes also strongly attenuates extravasation, metastatic burden and cancer stemness. These findings illuminate a mechanism whereby ether lipids in carcinoma cells serve as key regulators of malignant progression while conferring a unique vulnerability that can be exploited for therapeutic intervention. The contribution of ether lipid species in cancer cell fate has not been fully understood yet. Here the authors show that malignant cancer cells employ ether lipids to modulate membrane biophysical properties, enhancing iron endocytosis and ferroptosis susceptibility.

  PublisherDOI

• EPSILON: a method for pulse-chase labeling to probe synaptic AMPAR exocytosis during memory formation

  Nature Neuroscience · 2025-03-31 · 7 citations

  articleSenior authorCorresponding
  PublisherDOI

• Mechanism of Giant Magnetic Field Effect in a Red Fluorescent Protein

  Journal of the American Chemical Society · 2025-05-15 · 8 citations

  articleSenior authorCorresponding

  Several fluorescent proteins, when expressed in E. coli, are sensitive to weak magnetic fields. We found that mScarlet3 fluorescence in E. coli reversibly decreased by 21% in the presence of a 60 mT magnetic field, the largest magnetic field effect (MFE) reported in any fluorescent protein. Purified mScarlet3 did not show an MFE, but the addition of flavin mononucleotide (FMN) and simultaneous illumination with blue and yellow light restored the MFE. Through extensive photophysical experiments, we developed a quantitative model of the giant MFE in mScarlet3-FMN mixtures. The key reaction step involved electron transfer from fully reduced FMNH2 to triplet-state mScarlet3 to form a triplet spin-correlated radical pair. The magnetic field then controlled the branching ratio between singlet recombination vs triplet separation. Our quantitative model of the mScarlet3-FMN photocycle provides a framework for the design and optimization of magnetic-field-sensitive proteins, opening possibilities in fluorescent protein-based magnetometry, magnetic imaging, and magnetogenetic control.

  PublisherDOI

• Swimming motions evoke Piezo1-dependent Ca2+ events in vascular endothelial cells of larval zebrafish

  Current Biology · 2025-11-13 · 3 citations

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Electrophysiology in nanoscale compartments

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-09-04

  preprintOpen accessSenior authorCorresponding

  ABSTRACT Voltage-gated ion channels play important roles in many membrane-enclosed structures, including synaptic vesicles, endosomes, mitochondria, chloroplasts, viruses and bacteria. Here we study how compartment size and channel gating interact to shape voltage dynamics and ion content in sub-micron structures. In small compartments, assumptions underlying conductance-based (Hodgkin-Huxley type) models of membrane voltage must be relaxed: [1] stochastic gating of individual ion channels can quickly and substantially change membrane voltage; [2] these changes can equilibrate faster than channel state transitions; and [3] ionic currents, even through as few as two channels, can substantially alter ionic concentrations. We adapted conductance-based models to incorporate these effects, and we then simulated voltage dynamics of small vesicles as a function of vesicle radius and channel density. We identified regimes in this parameter space with qualitatively distinct dynamics. We then performed stochastic simulations to explore the role of Na V 1.5 in maturation of macrophage endosomes. The stochastic model predicted dramatically different dynamics compared to a deterministic approach. Electrophysiology of nanoscale structures can be very different from larger structures, even when ion channel composition and density are preserved. SIGNIFICANCE With tools of optical electrophysiology, one can measure and perturb membrane voltage in sub-micron structures. Recent experiments in organelles, dendritic spines, and bacteria motivate a re-examination of basic assumptions about bioelectrical phenomena in these compartments. This paper provides a framework for predicting and interpreting bioelectrical dynamics in small structures.

  PublisherOA PDFDOI

• Distribution of Eigenvalues of the Kohn Laplacian on Sphere Quotients

  ArXiv.org · 2025-09-14

  preprintOpen access1st authorCorresponding

  We prove a Weyl-type theorem for the Kohn Laplacian on sphere quotients as CR manifolds. We show that we can determine the fundamental group from the spectrum of the Kohn Laplacian in dimension three. Furthermore, we prove Sobolev estimates for the complex Green's operator on these quotient manifolds.

  PublisherOA PDFDOI

Recent grants

• NIH Grant DP2OD007428

  NIH · $2.5M · 2015

• Trapping single small molecules in solution

  NSF · $552k · 2009–2013

• Engineering Microbial Rhodopsins as Optical Voltage Sensors

  NIH · $371k · 2010–2014

• Brain-wide correlation of single-cell firing properties to patterns of gene expression

  NIH · $1.2M · 2018–2021

• Engineering Microbial Rhodopsins as Optical Voltage Sensors

  NIH · $1.1M · 2010–2014

Frequent coauthors

• Vicente Parot

  Pontificia Universidad Católica de Chile

  35 shared

• Christopher A. Werley

  34 shared

• Yoav Adam

  Hebrew University of Jerusalem

  32 shared

• Daan Brinks

  Delft University of Technology

  30 shared

• Peng Zou

  China Tobacco

  29 shared

• Dean A. Hendrickson

  West Virginia University

  28 shared

• Miao‐Ping Chien

  Erasmus MC

  25 shared

• Joel M. Kralj

  University of Colorado Boulder

  25 shared

Labs

• Adam E. Cohen LabPI

Education

• Ph.D., Neuroscience

  Harvard University

  2008

• B.A., Psychology

  University of California, Berkeley

  2002