Mice: The Visual-stimuli Four-arm Maze Test

based on:  https://pubmed.ncbi.nlm.nih.gov/34909455/

In a fascinating study published on Pubmed (November 2021), researchers have developed a novel tool for assessing cognitive and visual impairments in mice, particularly relevant to Alzheimer’s disease (AD). This innovative tool, named the Visual-stimuli Four-arm Maze (ViS4M or visual x-maze), promises to enhance our understanding of how neurodegenerative diseases affect vision and cognition.

Study Overview

The research team, led by Jean-Philippe Vit and colleagues, designed the ViS4M to evaluate both color and contrast vision alongside cognitive functions in mice. This versatile, x-shaped maze is equipped with spectrum- and intensity-controlled LED sources and dynamic grayscale objects, making it a comprehensive tool for studying various aspects of visual and cognitive impairments.

Key Features of the ViS4M

1. Color Vision Testing:
   • The maze is divided into four homogenous spaces, each with distinct chromaticity and luminance, tailored to the mouse visual system.
2. Contrast Sensitivity Testing:
   • Four grayscale objects are placed in the center of each arm, providing a contrast against the maze’s black walls and white floors.
3. Behavioral Tracking:
   • The maze allows for precise tracking of exploratory behavior, entry sequences, and transition patterns, providing detailed insights into the cognitive and visual functions of the mice.

Significant Findings

1. Healthy Wild-type Mice:
   • Wild-type (WT) mice showed spontaneous alternation between arms, even under equal illumination, indicating the use of both color and brightness cues for navigation.
2. Alzheimer’s Disease Model Mice:
   • Double-transgenic APPSWE/PS1ΔE9 mice (AD+ mice) exhibited significant deficits in alternation behaviors in both color and contrast modes, highlighting early impairments in color discrimination and contrast sensitivity.
3. Age-related Impairments:
   • The study also revealed that aging WT mice show distinct exploratory patterns compared to younger WT and AD+ mice, providing a nuanced view of how aging and AD affect vision and cognition differently.

Practical Applications

The ViS4M test is particularly valuable for profiling the progression of visual and cognitive impairments in neurodegenerative disease models. By analyzing the alternation pathways and exploration patterns, researchers can differentiate between functionally intact and impaired mice with high precision and reproducibility.

Conclusion

The introduction of the ViS4M test marks a significant advancement in behavioral neuroscience research. By enabling detailed assessments of color and contrast vision along with cognitive functions, this tool offers new avenues for understanding the complexities of neurodegenerative diseases like Alzheimer’s. As researchers continue to refine and utilize this tool, we can expect more insights into the intricate relationships between vision, cognition, and neurodegeneration.

For a deeper dive into the methodology and findings, you can access the full study on Pubmed.