Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/432450

Maternal immune activation specifically increases diagonal domain volume in the rat brain during early postnatal development

Wood, T. C.·Edye, M. E.·Harte, M. K.·Neill, J. C.·Prinssen, E. P.·Vernon, A. C.
View original source ↗Export metadata ↓

Abstract

Maternal immune activation (MIA) is consistently associated with elevated risk for multiple psychiatric and neurological disorders in the affected offspring. Converging lines of evidence from humans and animal models suggest a link between MIA and early entry into an atypical neurodevelopmental trajectory characterised by time- and sex-dependent abnormalities in brain structure and function. However to date, no such studies have investigated the brain-wide impact of MIA in the early post-weaning period, a critical and dynamic window of brain development. To address this, we acquired high-resolution ex vivo structural and diffusion tensor imaging (DTI) images from Wistar rat brains on postnatal day (PD) 21 following exposure to the viral mimetic poly (I:C) or sterile saline on gestational day (GD) 15 using a recently validated protocol. Using a combination of atlas-based segmentation and tensor based morphometry analysis we observed that MIA resulted in a significant increase in the relative volume of the diagonal domain (FDR q<0.1). Additional trend-level volume increases (p<0.05 uncorrected) were also found for the olfactory structures and preoptic area. Although not significant after FDR correction, we found trend-level evidence (p<0.05 uncorrected) for MIA x sex interactions in the volume of the diagonal domain, nucleus accumbens, pineal gland and anterior commissure. In contrast to volume, we found no evidence for microstructural alterations in our DTI dataset at PD21. These data provide new insights into the specific effects of MIA early in development, highlighting in particular, the diagonal domain as a target for future studies.

Explore related subjects

neurosciencePreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Wood, T. C., Edye, M. E., Harte, M. K., Neill, J. C., Prinssen, E. P., Vernon, A. C.. 2018-10-01. Maternal immune activation specifically increases diagonal domain volume in the rat brain during early postnatal development. https://doi.org/10.1101/432450

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Next generation Human Neocortical Neurosolver model with biophysically realistic somatic, dendritic and synaptic dynamics

The Human Neocortical Neurosolver (HNN) is an open-source biophysical modeling tool for multiscale interpretation of human electroencephalography (EEG) and magnetoencephalography (MEG) signals. HNN's foundation is a pre-tuned canonical neocortical circuit model consisting of excitatory pyramidal neurons and inhibitory interneurons in supra- (L2/3) and infragranular (L5) layers. This model was originally developed based on studies in rodent and non-human primate cortices when dynamics of human neurons were poorly characterized. Yet recent advances in recordings from human tissue now provide unprecedented detail to update the model. Here, we present a significantly updated model for use in the HNN software, with electrophysiological properties and synaptic connections tuned to human tissue. Beyond reproducing biologically realistic somatic dynamics, the pyramidal cells simulate dendritic calcium (Ca2+) spikes in the L5 extratelencephalic-projecting (ET) neurons, and shorter dendritic spikes in the L2/3 pyramidal neurons. We demonstrate how the updated circuitry and new features in the HNN software can be used to disentangle somatic, synaptic, and dendritic contributions to human E-/MEG signatures. The model is distributed with workflows to simulate event-related responses and oscillations, and tutorials demonstrating how membrane potentials, Ca2+ dynamics, and synaptic currents can be recorded and visualized. These enhancements allow extensive model validations based on in vitro and in vivo electrophysiology, voltage and Ca2+ imaging, and provide users with novel insights on the mechanisms underlying E-/MEG signals.

neuroscience↗
bioRxiv2026

A biological light sheet links cellular voltage to mesoscopic brain dynamics

Membrane voltage is the fundamental currency of neural computation, yet cellular-resolution voltage imaging of large neuronal populations in vivo remains limited by trade-offs among imaging speed, field of view, and optical sectioning. We overcome this challenge by encoding a biological light sheet in the brain: Selective Plane Expression (SPress) restricts fluorescent indicator expression to a user-defined, 20-m-thick plane, suppressing background at its source. Following one-time two-photon photoactivation, SPress enables standard widefield microscopes to capture high-contrast kilohertz voltage dynamics from hundreds of densely labeled neurons across millimeter-scale cortical sheets and columns in vivo. These recordings reveal mesoscopic subthreshold waves that flexibly reorganize population-wide spike timing, together with cellularscale wavefront microstructure that preserves stereotyped local recruitment biases. By shifting optical sectioning from instrumentation to gene expression, SPress makes kilohertz cellular resolution voltage imaging accessible across mesoscopic scales.

neuroscience↗
bioRxiv2026

Persistent hippocampal traces of lifelong spatial memory

Memory presents a biological paradox: the brain changes continuously, yet a brief experience can influence behavior for a lifetime. How such memories are stored in brain circuits remains unclear. Here we show that two days in a binary-tree maze leave mice with spatial memories that survive repeated 90-day absences over as much as a year. Across return visits, mice explored the maze more efficiently than when naive and resumed direct runs to a reward location sooner, both by a factor of 3. Chronic calcium imaging of the same hippocampal CA1 neurons showed that although most neurons had changed their preferred locations, the population activity at a given maze location still resembled the pattern from 90 days earlier. Furthermore, even when a neuron's place fields changed location, they tended to remain at the same branching level of the binary tree, reflecting the local geometry of the maze. In return sessions where the neural tuning for branching level was preserved more accurately, the mouse explored the environment more efficiently. Population patterns were best preserved near the reward location, and more reliable neural activity there accompanied earlier direct runs to the reward. With repeated experience, spatial representations changed less, both within a visit and across the long absences. A brief experience thus left selective hippocampal traces that survived months of absence despite drift, grew more durable with each return, and were correlated with memory in navigation behavior.

neuroscience↗