@article{18879,
  abstract     = {Our brain has remarkable computational power, generating sophisticated behaviors, storing memories over an individual’s lifetime, and producing higher cognitive functions. However, little of our neuroscience knowledge covers the human brain. Is this organ truly unique, or is it a scaled version of the extensively studied rodent brain? Combining multicellular patch-clamp recording with expansion-based superresolution microscopy and full-scale modeling, we determined the cellular and microcircuit properties of the human hippocampal CA3 region, a fundamental circuit for memory storage. In contrast to neocortical networks, human hippocampal CA3 displayed sparse connectivity, providing a circuit architecture that maximizes associational power. Human synapses showed unique reliability, high precision, and long integration times, exhibiting both species- and circuit-specific properties. Together with expanded neuronal numbers, these circuit characteristics greatly enhanced the memory storage capacity of CA3. Our results reveal distinct microcircuit properties of the human hippocampus and begin to unravel the inner workings of our most complex organ. },
  author       = {Watson, Jake and Vargas Barroso, Victor M and Morse, Rebecca and Navas Olivé, Andrea C and Tavakoli, Mojtaba and Danzl, Johann G and Tomschik, Matthias and Rössler, Karl and Jonas, Peter M},
  issn         = {1097-4172},
  journal      = {Cell},
  number       = {2},
  pages        = {501--514.e18},
  publisher    = {Elsevier},
  title        = {{Human hippocampal CA3 uses specific functional connectivity rules for efficient associative memory}},
  doi          = {10.1016/j.cell.2024.11.022},
  volume       = {188},
  year         = {2025},
}

@article{20099,
  abstract     = {The hippocampus, critical for learning and memory, is dogmatically described as a trisynaptic circuit where dentate gyrus granule cells (GCs), CA3 pyramidal neurons (PNs), and CA1 PNs are serially connected. However, CA3 also forms an autoassociative network, and its PNs have diverse morphologies, intrinsic properties, and GC input levels. How PN subtypes compose this recurrent network is unknown. To determine the synaptic arrangement of identified CA3 PNs, we combine multicellular patch-clamp recording and post hoc morphological analysis in mouse hippocampal slices. PNs can be divided into distinct “superficial” and “deep” subclasses, the latter including previously reported “athorny” cells. Subclasses have distinct input-output transformations and asymmetric connectivity, which is more abundant from superficial to deep PNs, splitting CA3 locally into two parallel recurrent networks. Coincident spontaneous inhibition occurs frequently within but not between subclasses, implying subclass-specific inhibitory innervation. Our results suggest two separately controlled sublayers for parallel information processing in hippocampal CA3.},
  author       = {Watson, Jake and Vargas Barroso, Victor M and Jonas, Peter M},
  issn         = {2211-1247},
  journal      = {Cell Reports},
  number       = {8},
  publisher    = {Elsevier},
  title        = {{Cell-specific wiring routes information flow through hippocampal CA3}},
  doi          = {10.1016/j.celrep.2025.116080},
  volume       = {44},
  year         = {2025},
}

@article{12515,
  abstract     = {Introduction: The olfactory system in most mammals is divided into several subsystems based on the anatomical locations of the neuroreceptor cells involved and the receptor families that are expressed. In addition to the main olfactory system and the vomeronasal system, a range of olfactory subsystems converge onto the transition zone located between the main olfactory bulb (MOB) and the accessory olfactory bulb (AOB), which has been termed the olfactory limbus (OL). The OL contains specialized glomeruli that receive noncanonical sensory afferences and which interact with the MOB and AOB. Little is known regarding the olfactory subsystems of mammals other than laboratory rodents.
Methods: We have focused on characterizing the OL in the red fox by performing general and specific histological stainings on serial sections, using both single and double immunohistochemical and lectin-histochemical labeling techniques.
Results: As a result, we have been able to determine that the OL of the red fox (Vulpes vulpes) displays an uncommonly high degree of development and complexity.
Discussion: This makes this species a novel mammalian model, the study of which could improve our understanding of the noncanonical pathways involved in the processing of chemosensory cues.},
  author       = {Ortiz-Leal, Irene and Torres, Mateo V. and Vargas Barroso, Victor M and Fidalgo, Luis Eusebio and López-Beceiro, Ana María and Larriva-Sahd, Jorge A. and Sánchez-Quinteiro, Pablo},
  issn         = {1662-5129},
  journal      = {Frontiers in Neuroanatomy},
  publisher    = {Frontiers},
  title        = {{The olfactory limbus of the red fox (Vulpes vulpes). New insights regarding a noncanonical olfactory bulb pathway}},
  doi          = {10.3389/fnana.2022.1097467},
  volume       = {16},
  year         = {2023},
}

@article{9438,
  abstract     = {Rigorous investigation of synaptic transmission requires analysis of unitary synaptic events by simultaneous recording from presynaptic terminals and postsynaptic target neurons. However, this has been achieved at only a limited number of model synapses, including the squid giant synapse and the mammalian calyx of Held. Cortical presynaptic terminals have been largely inaccessible to direct presynaptic recording, due to their small size. Here, we describe a protocol for improved subcellular patch-clamp recording in rat and mouse brain slices, with the synapse in a largely intact environment. Slice preparation takes ~2 h, recording ~3 h and post hoc morphological analysis 2 d. Single presynaptic hippocampal mossy fiber terminals are stimulated minimally invasively in the bouton-attached configuration, in which the cytoplasmic content remains unperturbed, or in the whole-bouton configuration, in which the cytoplasmic composition can be precisely controlled. Paired pre–postsynaptic recordings can be integrated with biocytin labeling and morphological analysis, allowing correlative investigation of synapse structure and function. Paired recordings can be obtained from mossy fiber terminals in slices from both rats and mice, implying applicability to genetically modified synapses. Paired recordings can also be performed together with axon tract stimulation or optogenetic activation, allowing comparison of unitary and compound synaptic events in the same target cell. Finally, paired recordings can be combined with spontaneous event analysis, permitting collection of miniature events generated at a single identified synapse. In conclusion, the subcellular patch-clamp techniques detailed here should facilitate analysis of biophysics, plasticity and circuit function of cortical synapses in the mammalian central nervous system.},
  author       = {Vandael, David H and Okamoto, Yuji and Borges Merjane, Carolina and Vargas Barroso, Victor M and Suter, Benjamin and Jonas, Peter M},
  issn         = {1750-2799},
  journal      = {Nature Protocols},
  number       = {6},
  pages        = {2947–2967},
  publisher    = {Springer Nature},
  title        = {{Subcellular patch-clamp techniques for single-bouton stimulation and simultaneous pre- and postsynaptic recording at cortical synapses}},
  doi          = {10.1038/s41596-021-00526-0},
  volume       = {16},
  year         = {2021},
}