4: Dissociation

Dissociation is a defense mechanism that acknowledges what is perceived, but strips events of their emotional impact. Unlike denial, a person in a dissociative state acknowledges the facts that are plainly observable, and even grants credence to the allegations of others - what is denied is merely the emotional impact that they should have.

For example, a person who decides against a medical procedure for a parent may consider that the operation carries a high risk, has debilitating side effects, and even if successful will not extend their life by much - but refuse to consider their emotional attachment to their parent.

In that example, the ability to dissociate or to "put one's emotions aside" for the sake of making a rational choice is considered entirely rational - but in other instances dissociation seems an irrational choice and may even be classified as a mental disorder.

The author mentions a "possession trance" as a form of dissociation, in which an individual recognizes their actions but denies personal responsibility for initiating them - claiming to have been under the control of a supernatural force.

Stupor is another form of dissociation, in which a person simply refuses to react to stimuli. He may hear a person call his name but refuse to react in any way, or to hold still even when someone inflicts pain upon him - recognizing that damage is being done to his body, but not being concerned enough to react.

(EN: The author also lists amnesia and fugue as dissociations, but my sense is that those are of a different nature in that the individual refuses to acknowledge the facts themselves, not merely the consequences.)

The author reiterates that ego defenses are not mutually exclusive or a clearly separate set of categories, such that a person may be in denial of some things, repress others, and dissociate from others still. Or the defenses may evolve from one another - as a patient who previously denied something now acknowledges it, but remains dissociated from it.