I've been talking to my therapist a lot about what caused my BPD, Experts/researchers believe it's a combination of biological, environmental, and hereditary.
Biological: People with BPD are said to have an enlarged and overactive Limbic system, especially Amygdala. The Limbic system supports a variety of function including emotion, behavior, motivation, and long-term memory. It's primary function is emotional life (are you seeing how this relates to people with BPD?). According to wiki, " the amygdalae perform primary roles in the formation and storage of memories associated with emotional events. The amygdala, especially the basolateral nuclei, are involved in mediating the effects of emotional arousal on the strength of the memory for the event." People who are exposed to trauma in childhood are unable to tell a linear history of that time. There are parts of my childhood I only know exist through pictures, and while I can remember certain events in details the details of when and where are often foggy. Often I'll remember different events as happening within a short time frame of each other, when in reality they may have happened years apart.
Hereditary: Research show that the temperament a someone inherits can contribute to the onset of BPD. I inherited my Dad's, very sensitive, This combined with my biological factors played a big role in developing my disorder. As a child I was super sensitive, very stubborn, cried at the drop of a hat, and I hated being punished.
Environment: This aspect played a huge role in the onset of my disorder. I was emotionally and psychologically abused by my step mother, I dealt with a lot of loss in a short time frame (parents divorcing, grandmother dying, moving, Dad moving out) which my brain didn't respond to like others, and unfortunately neglected in some way by both my parents. Unfortunately neglect isn't always obvious and does not always come in the form of not feeding your kids or leaving them alone for hours. When my parents divorced and my Father re-married he continuously chose his wife over his kids, and I sadly was not as close to him. Living with my Mother was hard because he and my sister were much closer and I often felt like an outcast. When I was a little older (late teens) I got in really bad fights with my Mom, and I often felt like she favored my sister over me (sometimes she'd get away with stuff I got in trouble for). I am certain my parents weren't neglectful on purpose, but because of my head, because of my temperament I didn't get the amount of attention I needed.
It's hard to talk about this stuff out loud. I feel like I'm blaming people for my problems. But, I've never talked about like I have been. I guess it feels good to get it out.