We don‘t use the mind to choose what emotions we want to work with. We simply allow emotions come up and usually the stronger the emotion is, the faster it will jump out.
Take me for an example, I do breathing exercise everyday to allow emotions come up and feel what emotions I have been suppressing. Most people have suppressed their emotions so much that intellectually they think they are one way, but in reality, they are another way. For instance, if a person think he/she is peaceful but get annoyed or frustrated by outside circumstances. Then this person has supressed emotions and the event serves to trigger his/her suppressed emotions. Psychologists call those subconscious emotions or beliefs. Most people project their own feelings and expectations on other people and outside circumstances. When a person close their heart that they become angry or frustrated which are fear based. In most cases, they are afriad of losing control and completely letting go.
Anger and fear are blocking/capping emotions. The real causal emotions are grief and shame that one has denied and suppressed.
Founder of MasterSource Spiritual Guidance