The human brain has evolved to help us do some really clever things that no other species is capable of. For example, we can overcome really complicated challenges, problem solve, we can be creative and develop new things like technology. Unfortunately, the brain is also capable of creating highly negative emotions that we can struggle to understand or manage. It can also do this when we think about the future, or pains from the past, or when we attack ourselves with criticisms and judgements.

If we had a say in how our brains developed, we probably would not have chosen to include these less helpful processes, unwanted thoughts, images, or emotions. However, we did not have a choice, and it is not our fault that our brains evolved this way.

The other problem with our brains is that they do not know the difference between the past, present and future threats. Internal and external threats are treated exactly the same way by our brain, and this is where the first of these emotional systems comes in, the threat system.