Are Horses That Crib Cognitively Impaired?

Cribbing is a familiar stereotype in horses that is believed to help horses handle stressful situations. It has been theorized that horses that develop cribbing behaviors are less-flexible thinkers than those horses that don’t crib because of a sensitization of the basal ganglia in the brain. Wild horses to do not crib.

Cribbing, where the horse places his top teeth on a fixed structure and contracts the lower-neck muscles, has no obvious function. Cribbing appears to arise during periods of chronic stress; a genetic predisposition may also be at play.

A Swiss study determined that horses that crib are just as capable of solving problems as their non-cribbing counterparts. Researchers S. Freymond, A. Ruet, M Grivaz, C Fuentes and K. Zuberbühler amd I. Bachmann found that all the 13 horses used in their study were able to recognize symbols and solve conclusion exercises, which are difficult for horses. The caveat? The horses had to be able to crib when asked to perform these tasks, which relieved their stress.

The four-part study was designed to determine if certain regions of the brain are impaired, which would limit learning outcomes. It used six horses that cribbed and seven control horses. They horses had to learn the difference between two colored symbols: A circle and a cross on a white or black background. The symbols were attached to two feed flaps in a random order; once the horse learned the correct symbol and pushed the flap, they were rewarded with food.

Once the horse completed the task six times, the goal was reversed and touching the original symbol produced no food. This step was the most difficult for the horses and required the most attempts. However, the horses were able to solve the second reversal question more quickly.

The scientists found no difference in the cognitive abilities of cribbers and non-cribbers in the study. They noted that the difference in their study and others that have been conducted is that the researchers allowed the horses to crib when they chose to.