In an unprecedented leap forward in neuroscience, researchers have unveiled groundbreaking findings that elucidate the phenomenon of microstates in rodent electroencephalography (EEG). While microstates—transient, quasi-stable patterns of electrical activity in the brain—have been extensively studied in humans, this pioneering study extends the concept to rats, shedding light on fundamental mechanisms of brain function and offering new vistas for translational psychiatry. The study, led by Piorecka, V., Vejmola, C., Peskova, P. et al., was published on November 21, 2025, in Translational Psychiatry, marking a milestone in cross-species neural dynamics research.
Microstates are brief periods, milliseconds in duration, during which the brain’s global electrical activity exhibits a consistent topographic pattern. In humans, these microstates are thought to represent the ‘building blocks’ of cognitive processing and reflect coordinated brain network activity underlying perception, attention, and consciousness. Until now, capturing these subtle but revealing electrical signatures in non-human animals has been technically challenging due to differences in brain architecture and EEG recording methodologies. This study innovatively bridges that gap by demonstrating that rats too display definable microstate dynamics, providing a powerful preclinical platform to explore neuropsychiatric disorders.
The researchers employed advanced EEG recording techniques adapted for the rodent brain, ensuring high-resolution temporal and spatial data acquisition. Their methodology involved recording electrical activity from the cortical surface while rats engaged in resting and behavioral tasks. By applying computational algorithms traditionally used in human EEG microstate analysis, the team uncovered distinct microstate classes in rat EEG data, analogous in temporal parameters and spatial topographies to human counterparts. This approach validates the translational potential of rodent microstate research to human cognitive neuroscience.
One of the study’s most compelling findings is that rat microstates are characterized by a unique repertoire of topographies that persist for tens of milliseconds, mirroring human EEG microstate durations. Such temporal stability indicates an organized neural basis for these microstates across species. This revelation challenges assumptions that microstates are exclusive to the complex human cerebral cortex, instead positing that microstate-like phenomena may be a fundamental neurophysiological principle conserved through evolution.
The authors also explored how different behavioral states influence microstate dynamics in rats. They discovered that transitions between microstate classes correlated with changes in behavioral context, akin to observations in human EEG studies where microstate configurations fluctuate with cognitive demands and emotional states. This behavioral linkage confirms that rat microstates are not ephemeral artifacts, but robust neural signatures tied to brain function.
Another salient component of the study was the examination of microstate alterations induced by psychopharmacological manipulations. By administering drugs affecting neurotransmitter systems implicated in psychiatric disorders, the team observed predictable modulations in microstate parameters. These pharmacological effects underscore the utility of rat microstate analysis in preclinical models for drug development and screening for psychiatric therapeutics.
Technically, the study leverages machine learning and sophisticated signal processing pipelines to segment continuous EEG data into discrete microstates. This automated classification enables objective quantification of microstate features such as duration, occurrence, and transition probabilities. Such detailed characterization surpasses traditional EEG analyses and opens avenues for detailed mechanistic insights into brain network dynamics underpinning behavior and mental health.
The implications of this proof-of-concept study are vast and multifaceted. By establishing microstate analysis in rats, researchers now have access to a powerful experimental platform where invasive techniques, genetic manipulations, and longitudinal studies can elucidate the neural substrates of microstate phenomena. This addresses a critical limitation in human EEG research, where non-invasive recordings restrict mechanistic explorations.
Moreover, this research paves the way for innovative translational applications. Microstate abnormalities are emerging biomarkers in psychiatric conditions such as schizophrenia, depression, and bipolar disorder. Understanding how these microstate configurations arise, stabilize, or degrade in animal models that recapitulate human psychopathologies can accelerate the development of targeted interventions and personalized medicine strategies.
The study also emphasizes the evolutionary conservation of brain network dynamics. By pinpointing microstates in rodents, the findings suggest that the neural architecture responsible for generating these patterns is deeply rooted in mammalian brain organization, reflecting fundamental principles of cognitive processing and consciousness. This cross-species perspective invites a reevaluation of how we conceptualize mental processes in non-human animals.
From a methodological standpoint, the successful adaptation of human EEG microstate analytical frameworks to rats signifies a methodological breakthrough. It underscores the value of interdisciplinary approaches combining neuroengineering, computational neuroscience, and behavioral neurobiology. Such integration is vital to unravel the complex interactions between neuronal populations that manifest as emergent global electrical states.
The researchers also highlight that while similarities exist between human and rodent microstates, species-specific differences in microstate topology and dynamics reflect divergent anatomical and functional brain features. Careful comparative analyses will be essential to interpret translational findings appropriately, ensuring that rodent models accurately recapitulate key aspects of human brain function.
In addition to behavioral correlations, the study reveals that microstate transitions exhibit non-random patterns influenced by underlying neural oscillations and connectivity networks. This insight suggests that microstates are emergent properties of coordinated neuronal ensembles engaging transiently to support information processing. Deciphering these interactions at fine temporal scales enriches our understanding of brain function beyond traditional firing rate or connectivity metrics.
Critically, the team calls for future research incorporating simultaneous EEG and invasive electrophysiological recordings in rodents to map microstates onto cellular and circuit-level processes. Such multimodal approaches will clarify how neuronal spiking and synaptic interactions generate the macroscopic microstate activity observed in EEG. This multilayered analysis is poised to unravel the biological meaning of microstates and their relevance to cognition and disease.
This pioneering study stands at the forefront of neural network research, promising to revolutionize how we investigate brain states and their perturbations in health and disease. By demonstrating that rats share key microstate properties with humans, it establishes a vital translational bridge, fostering advancements in psychiatric research, neuropharmacology, and cognitive neuroscience.
In summation, the proof-of-concept achievement of detecting and characterizing microstates in rat EEG not only validates a novel biomarker for brain function but also opens a rich vein of scientific inquiry into the neural bases of cognition, emotion, and neuropsychiatric disorders. The work of Piorecka et al. heralds a new era in which rodent models can be intimately leveraged to decipher the complexities of brain network dynamics observable non-invasively in humans.
Subject of Research: Neural microstates as observed in electroencephalography (EEG) of rats, investigating their similarities with human EEG microstates to advance translational psychiatry.
Article Title: Microstate in rats’ EEG: a proof of concept study.
Article References:
Piorecka, V., Vejmola, C., Peskova, P. et al. Microstate in rats’ EEG: a proof of concept study. Transl Psychiatry 15, 494 (2025). https://doi.org/10.1038/s41398-025-03702-y
Image Credits: AI Generated
DOI: 10.1038/s41398-025-03702-y (Published November 21, 2025)
