Work

The mirror preference test: A reverse translational approach to study anomalous subjective experience in rats

Year: 2025

Type: article

Abstract: Significant advancements have been made in the treatment of psychotic disorders, yet current pharmacotherapy remains inadequate. Symptoms related to the misinterpretation of reality are crucial for diagnosis but pose challenges for preclinical research. In humans, a Mirror-Gazing test is used to examine abnormal self-experience and to predict the risk of schizophrenia. To address this, we developed a task to evaluate anomalous subjective experiences in rats using a Mirror-Preference test. Here we demonstrate that naive rats show a preference for a mirror chamber, which was followed by significant habituation over a series of trials. In subsequent tests, we utilized dimmed lighting and net-covered mirrors to induce incomplete mirror images. Acute stimulation with amphetamine (AMPH, 3 mg/kg, i.p.) further increased the preference for the mirror. In a model of psychosis induced by chronic AMPH administration, rats showed fewer and shorter interactions with the mirror but maintained their preference for the chamber where psychotic-like animals were given additional AMPH stimulation (1.5 mg/kg, i.p.) before testing. Here, a surprising reversal in chamber preference was observed, along with decreased frequency and duration of mirror contact, suggesting mirror avoidance. The AMPH-presensitized rats also exhibited hyperlocomotion and elevated anxiety, indicative of psychotic-like behaviour. Although self-recognition in rodents is debatable, recent studies suggest they can discriminate mirror images. We propose that limited visual perception that meets brain monoamine sensitization may trigger visual illusions as part of a psychotic-like state in rats. This novel approach can be utilized to test intervention strategies for psychosis in rats. • A task to evaluate anomalous subjective experiences in rats using a mirror test was developed. • Naive rats show a preference for a mirror chamber, but with a significant habituation. • Acute stimulation with amphetamine (3 mg/kg, i.p.) increased the preference for the mirror. • In a model of psychosis, rats showed fewer and shorter interactions with the mirror. • Psychotic-like animals with additional amphetamine (1.5 mg/kg, i.p.) show a reversal of the mirror preference.

Source: Brain Research Bulletin

DOI: 10.1016/j.brainresbull.2025.111247

Authors: Daria Chestnykh, Liubov S. Kalinichenko, Stephan von Hörsten, Johannes Kornhuber, Christian P. Müller

Institutions: Friedrich-Alexander-Universität Erlangen-Nürnberg, Universitätsklinikum Erlangen, Heidelberg University, Central Institute of Mental Health, Medizinische Fakultät Mannheim

Language: English

Topic: Schizophrenia research and treatment

Subfield: Psychiatry and Mental health

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,280