USMLE® Step 1 style questions USMLE
USMLE® Step 2 style questions USMLE
A 35-year-old man comes to the clinic because he has been feeling "strange" since he was a passenger in a violent motor vehicle collision 6 months ago. He was uninjured in the trauma, but states that he has often felt like he is "living in a movie" since that time. He has been reprimanded at work for apparent "daydreaming" and is afraid that he may lose his job. His medical history is noncontributory. Family history is significant for depression in his mother and brother. He denies ever using alcohol, tobacco, or recreational drugs. His temperature is 37.0°C (98.6°F), pulse is 79/min, respirations are 14/min, and blood pressure is 128/84 mm Hg. Physical examination shows a male who appears mildly anxious with downcast eyes. Routine laboratory studies show no abnormalities. Which of the following is the most likely diagnosis?
Maybe you’ve had the experience of driving on “autopilot.”
One minute you got in your car, and the next minute you’ve arrived at your destination, but you can’t actually remember the details of the drive.
This is an example of normal, everyday dissociation, a term that describes a mental state of disconnection from what’s going around you.
This daydream-like state doesn’t normally last very long, and most people can snap out of it if something or someone requires their attention.
But for some people, dissociation is more pervasive, and can’t be turned off so easily.
In fact, this feeling of “disconnectedness” may become so intense and happen so often that it stops a person from functioning in their daily life.
When this is the case, we say the person has a dissociative disorder.
Dissociative disorders are a group of disorders that impair awareness of your own actions, thoughts, physical sensations, and even your identity, or sense of who you are.
Dissociative disorders stem usually stem from trauma (usually early childhood abuse or neglect) and are thought to be a way of adapting to negative feelings and experiences.
Dissociative disorders are divided into three main types: depersonalization/derealization disorder, dissociative amnesia, and dissociative identity disorder.
Each of these disorders can be lined up along a spectrum of severity, with depersonalization/derealization disorder being the least severe of the dissociative disorders, dissociative amnesia falling somewhere in the middle, and dissociative identity disorder being the most severe.
Typically, individuals with more severe dissociative disorders have elements of less severe ones as well.
With depersonalization/derealization disorder, depersonalization refers to a feeling of detachment from oneself, of one’s own person, while derealization refers to a feeling that that the world around you is not fully real.
Those with the disorder often feel as if they’re watching themselves from the outside, like they’re watching a movie about their life.
They might feel emotionally or physically numb, or have a weak sense of self.
Individuals with depersonalization/derealization disorder might speak in a deadpan manner, with little emotion, and have trouble forming relationships.
In severe cases, a person might have trouble recognizing familiar places, people, or objects, which can make it had to learn tasks.
Other symptoms include an altered sense of time, where things seem to move too fast or slow, brain fog or light-headedness, and being prone to rumination and anxiety.
Dissociative amnesia is when a person blocks out or forgets important personal information that most people would remember for a lifetime, like where they lived as a child, or what their mother was like.
Dissociative amnesia can be divided into four types: localized, generalized, systematized, and continuous.
Most people with dissociative amnesia have localized amnesia, meaning they have trouble recalling a traumatic event.
Sometimes the memory loss is broader, and includes months or years surrounding the event.
Generalized amnesia is where a person can’t remember any of their past, even the non-traumatic parts.
The onset of generalized amnesia can be sudden, stress-induced, and may be accompanied by a dissociative fugue, meaning a temporary period of disorientation and wandering or travel.
In a fugue state, a person may be confused about who they are, or they may believe they are someone else.
They may also temporarily lose deeply-ingrained skills. For example, a computer engineer might forget how to use a laptop.
In systematized amnesia, a person only forgets a category of information in some way associated with a trauma, like forgetting everything about a certain person, or a specific location, even if it was a significant part of their life.