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Frontiers in veterinary science2024; 11; 1470039; doi: 10.3389/fvets.2024.1470039

Non-invasive scalp recording of electroencephalograms and evoked potentials in unanesthetized horses using a 12-channel active electrode array.

Abstract: Despite the long history of the horse-human bond, our understanding of the brain and mind of horses remains limited due to the lack of methods to investigate their brain functions. This study introduces a novel methodology for completely non-invasive, multi-channel recording of electroencephalography (EEG) and evoked potentials in awake horses to examine equine auditory cortical processing. The new approach utilizes specially designed brush-shaped active electrodes that facilitate stable signal acquisition through the hair coat by penetrating electrode pins and integrated pre-amplifiers. A 12-channel electrode array provided greater scalp coverage than prior work. As a proof of concept, clear cortical auditory evoked potentials (CAEPs) were recorded in response to sound onsets and offsets. The equine CAEP waveform morphology resembled the human P1-N1-P2-N2 complex, although the latencies were shorter than typical human values. The CAEP amplitudes were maximal at centroparietal electrodes, contrasting with the frontocentral distribution seen in humans, potentially explained by differences in auditory cortex orientation between species. This non-invasive multi-electrode method enables the evaluation of cognitive abilities, normal and abnormal brain functions, and advances scientific understanding of the equine mind. It offers potential widespread applications for recording EEGs and evoked potentials in awake horses and other medium-to-large mammalian species.
Publication Date: 2024-12-02 PubMed ID: 39687848PubMed Central: PMC11647030DOI: 10.3389/fvets.2024.1470039Google Scholar: Lookup
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  • Journal Article

Summary

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The research presents a new methodology of using a 12-channel active electrode array for non-invasive recording of electroencephalography (EEG) and auditory evoked potentials in awake horses. The developed method can provide greater insights into the cognitive abilities, normal and abnormal brain functions of horses, thus enhancing the scientific understanding of their minds.

Introduction

In this study, the researchers introduced a novel method for investigating the brain functions of horses. Traditionally, understanding equine brain and mind has been limited because of the lack of suitable methodologies. The research focuses primarily on the experimental recording of electroencephalography (EEG) and evoked potentials from horses that are awake.

Methodology

  • The new method utilizes specially designed brush-shaped active electrodes. These electrodes can penetrate the hair coat of the horses to acquire stable signals.
  • The electrodes also integrate pre-amplifiers, which play a crucial role in the enhancement of the signals before they are processed.
  • A distinctive feature of the new methodology is the use of a 12-channel electrode array. This offers more scalp coverage than prior methods used in similar research.

Results and Discussion

  • As part of their proof of concept, the researchers recorded clear cortical auditory evoked potentials (CAEPs) from the horses. These potentials were observed in response to sound onsets and offsets.
  • The waveform morphology of the equine CAEPs bore a resemblance to the human P1-N1-P2-N2 complex. However, the researchers note that the latencies observed in horses were shorter than the typical values found in humans.
  • The maximum CAEP amplitudes occurred at the centroparietal electrodes. This contrasts with the frontocentral distribution that is usually seen in humans. The researchers suggest that these differences might be due to the differences in auditory cortex orientation between the two species.

Conclusion and Future Research

Their method, which was described as non-invasive and multi-electrode, could potentially be used to evaluate cognitive abilities and brain functions in horses. Both normal and abnormal brain functions can be analyzed using this method. This can further enhance and advance the scientific understanding of the equine mind. The researchers concluded by stating that their method offers potential widespread applications beyond horses with possible usage in recording EEGs and evoked potentials in other medium-to-large mammalian species.

Cite This Article

APA
Itoh K, Kikumura N, Maeda T, Hirata S, Ringhofer M. (2024). Non-invasive scalp recording of electroencephalograms and evoked potentials in unanesthetized horses using a 12-channel active electrode array. Front Vet Sci, 11, 1470039. https://doi.org/10.3389/fvets.2024.1470039

Publication

ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 11
Pages: 1470039

Researcher Affiliations

Itoh, Kosuke
  • Center for Integrated Human Brain Science, Brain Research Institute, Niigata University, Niigata, Japan.
Kikumura, Norihide
  • Faculty of Life and Environmental Sciences, Teikyo University of Science, Uenohara, Japan.
Maeda, Tamao
  • Wildlife Research Center, Kyoto University, Kyoto, Japan.
  • Research Center for Integrative Evolutionary Science, The Graduate University of Advanced Science (SOKENDAI), Hayama, Japan.
Hirata, Satoshi
  • Wildlife Research Center, Kyoto University, Kyoto, Japan.
Ringhofer, Monamie
  • Faculty of Life and Environmental Sciences, Teikyo University of Science, Uenohara, Japan.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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