There is a really interesting article at this link titled "Spatial Reasoning and Laterality Affect Riding Horses' Behavior"
It's a summary of a research that was presented at at the sixth International Equitation Science Conference in Uppsala, Sweden, on July 31, 2010, and deals with how some horses seem to be able to asses situations and find the shortest way instead of just choose a preferred direction around an obstacle.
http://www.thehorse.com/ViewArticle.aspx?ID=16808
Thanks for sharing that with us all Kicki...interesting