Lateral vision in horses: a behavioral investigation.

This study explores the lateral vision (side vision) of horses from a behavioral aspect, by using a unique experimental design and real-life stimuli. The results of the research indicate that horses are capable of detecting and identifying objects located within most of their panoramic field of view.

Introduction and Methodology

• Researchers carried out a study to examine lateral vision in horses, marking the first time such an investigation had been done from a behavioral perspective.
• The experiment involved three horses and implemented an innovative design to ascertain the range of the animals’ lateral (side) and caudolateral (rear-side) vision as it pertains to stimulus detection and discrimination.
• The setup engaged a curvilinear wall, where real-life stimuli were presented in one of four positions and at top or bottom heights on both sides of the horse.
• Two different tests were conducted: One was to determine if the horses could detect the correct stimulus when paired against a control; the other was to find out whether the horses could discriminate the correct stimulus when paired against another object.
• In order to indicate whether they detected or recognized the correct stimulus, the horses were trained to push one of two paddles.

Key Findings

• All the horses were able to detect the correct stimulus significantly more than chance would allow, irrespective of the stimulus’s position or location.
• The horses accurately discriminated between stimuli when the objects were located in positions A, B, and C, regardless of whether they were placed at the bottom or top locations.
• However, when stimuli were placed at position D, the horses failed to differentiate between them.

Conclusions and Implication

• The findings of this research back up physiological descriptions of the equine eye.
• Furthermore, it contributes new behavioral data, demonstrating that horses are capable of detecting objects within a nearly full circle all around them.
• This research also shows that horses can identify individual objects within most – but not all – of their panoramic field of view.
• This information helps to enhance our understanding of the capabilities and limitations of equine vision, which could have practical implications for the way we handle horses in various settings.