The universal trigger for fear is the threat of harm, real or imagined. This threat can be for our physical, emotional or psychological well-being. While there are certain things that trigger fear in most of us, we can learn to become afraid of nearly anything.
Fear can be learned through direct experience with a threat, but it can also be learned via social means such as verbal warnings or observ-ing others. ... These findings demonstrate that the amygdala is in-volved in learning fear even without direct experience with the aversive event.
Primary osteoarthritis is mostly related to aging. With aging, the water content of the cartilage increases and the protein makeup of cartilage degenerates. Repetitive use of the joints over the years causes damage to the cartilage that leads to joint pain and swelling
