I am responding to the assertion that "sometimes you need a good amount of fear or anxiety to kick you in the ass..." This supposition is not merely factually f

I am responding to the assertion that "sometimes you need a good amount of fear or anxiety to kick you in the ass..." This supposition is not merely factually false, but is actually dangerously harmful, especially to one's mental (but also physical) health. First, what's important to realize is, when you say it can be positive, you are thinking of incidental stressors. But that's not the case here. The sort of fear/anxiety that occurs is constant and long term, rather than incidental (e.g. worrying about something abstract, rather than fleeing from a predator). Indeed, incidental stress can be / often is productive. However, it differs fundamentally from anxiety, which is considered a mental disorder that results among others when fear / mental stress become long term / constant (such as when worrying about an abstract notion that has no direct effect on one's situational survival). Anxiety adversely affects the amygdala and hippocampus, in particular. It causes a growth in the former, which results in intensified bodily responses to anxiety; so in that sense, it acts as a positive feedback loop that worsens the effects of anxiety as time goes on. At the same time, long term effects result in the hippocampus shrinking, which reduces a person's ability to form long term memories, or contextualize emotional responses. Needless to say, that in itself severely curtails the ability to reason on a higher level.