Differential place and response learning in horses displaying an oral stereotypy.

The research investigates the difference in learning patterns between horses that display an oral stereotypy (repeating physical behaviors) and those who don’t. The findings suggest that horses with this phenomenon primarily use ‘response’ learning and this form of learning may increase due to stress-related effects on the brain.

Research Background

• Oral stereotypy in horses refers to repeated, fixed behaviors like crib-biting or wood-chewing. Earlier studies have identified a link between these behaviors and conditions of chronic stress or environmental deprivation.
• In humans and animals, stress and exposure to certain drugs have been found to alter midbrain neurophysiology in a comparable manner, causing a switch from response-outcome (R-O) to stimulus-response (S-R) learning style. R-O learning is where the organism changes its behavior based on the result of previous experiences, while in S-R learning, cues in the environment trigger the organism’s behavior.
• This study seeks to explore this altered learning pattern in horses displaying oral stereotypy. Recognizing such changes could contribute valuable data towards the development of a model for the causes of stereotypy.

Research Methodology

• The researchers conducted three experiments using variations of the place/response paradigm, a common method in determining learning styles. This involved setting up tasks for the horses to teach them how to get through a maze, and modifying the entrance points and directions to encourage different learning styles.
• The control group was composed of horses that did not display oral stereotypy.

Research Findings

• The initial experiment revealed that crib-biting horses tended to rely on ‘response’ learning after 20 trial sessions. The control group, on the other hand, leaned toward ‘place’ learning.
• When the maze entry points and directions were modified, the crib-biting horses accomplished the task faster than in the previous experiment.
• In the final experiment, an arena test confirmed that crib-biting horses are capable of ‘place’ learning, although they evidently prefer ‘response’ learning.

Implications

• This is the first study to show that horses exhibiting oral stereotypy prefer ‘response’ learning, a learning style often linked with stress and brain activity modifications.
• The research provides valuable insights for the development of models determining the causes of stereotypy, and the potential connection between this behavioral phenotype, chronic stress, and changes in learning patterns.