Humans are hardwired to remember things that threaten or are very rewarding to them. You have learned that what is threatening may be painful and what is rewarding may offer pleasure. These pleasures and pains trigger emotions that elevate the status of any would-be memory.
Individuals with defensive or low self-esteem typically focus on trying to prove themselves or impress others. They tend to use others for their own gain. Some act with arrogance and contempt towards others. They generally lack confidence in themselves, often have doubts about their worth and acceptability, and hence are reluctant to take risks or expose themselves to failure. They frequently blame others for their shortcomings rather than take responsibility for their actions.
Humans are learning machines. When you learn, you organize, shape, and strengthen your brain. A hundred billion or more nerve cells are crammed into three pounds of complex tissue inside your skull. From the day you are born and even before, your brain is ready to capture your experiences and encode them into a web of connections. These connections are the nuts and bolts of the learning machine that is the human brain.
So much of what you achieve results from a lifetime of decisions, large and small. You choose your clothes, job, relationships and everything in between. Your choices may lead you to the peak of your potential, or leave you meandering in the valleys of doubt and guilt. Yet despite their power, most decisions happen so automatically you barely even realize you're making them.