Borderline Personality Disorder is a difficult disorder to understand and treat. Briefly, people who suffer from BPD tend to have a heightened sensitivity to rejection. When they feel that they are being rejected they can react with strong feelings of anger. Their emotions can be very intense and vary widely during the day. This can also make their relationships very unstable. They can also be very impulsive. However, a recent fascinating piece of research used a mobile device and what’s called an “experience sampling” technique to gain further insight into what it is like to have BPD. In this episode I discuss that research and then wonder what else we might be able to learn as our mobile devices become even more powerful.