Thursday, July 7, 2011

Dopamine and Dementors



Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope, and happiness out of the air around them... Get too near a Dementor and every good feeling, every happy memory will be sucked out of you. If it can, the Dementor will feed on you long enough to reduce you to something like itself...soulless and evil. You will be left with nothing but the worst experiences of your life.
-- Remus Lupin to Harry Potter
Harry Potter and the Prisoner of Azkaban

Been there?

While we wait with bated breath for the final episode of the Harry Potter movie series, here is a post on the neuroscience of Harry's worst nightmare.

Dementors, you see, are dopamine depleters.  They are not to be messed with.

Neither is any other kind of dopamine depletion.  Here is one clinical case, an experiment conducted on one highly-functional, never-a-whiff-of-mental-disturbance 21-year-old who received a dopamine depleting drug over the course of 25 hours.

  • Mr. A was a healthy, extraverted, very well functioning 21-year-old medical student without even minor psychological difficulties or psychiatric disorders in his family. His Global Assessment of Functioning Scale score was 97. Written informed consent was obtained from Mr. A. We will describe the spontaneous reported subjective experiences after he started the first dose of 750 mg AMPT at t=0 hours (1).
  • After 7 hours, Mr. A felt more distance between himself and his environment. Stimuli had less impact; visual and audible stimuli were less sharp. He experienced a loss of motivation and tiredness. After 18 hours, he had difficulty waking up and increasing tiredness; environmental stimuli seemed dull. He had less fluency of speech. After 20 hours, he felt confused. He felt tense before his appointment and had an urge to check his watch in an obsessive way.
  • After 24 hours, Mr. A had inner restlessness, flight of ideas; his ideas seemed inflicted, and he could not remember them. He felt a loss of control over his ideas. After 28 hours, he felt ashamed, frightened, anxious, and depressed. He was afraid that the situation would continue. At that time, blepharospasm, mask face, and tremor were noted. After 30 hours, he was tired and slept 11 hours. After 42 hours, he had poor concentration. In the next hours, he returned to normal.

Yup.  You can understand how dementors made good prison guards, and why the wizarding world was astounded when Sirius Black escaped.  Who could even get off the sofa?

Certain psychotropic meds have a dopamine depleting effect, most notably the antipsychotics used to treat schizophrenia and bipolar disorder.  Okay, Mr. A got an experimental dose.  This is not a riff on how psychiatry is an arm of the Dark Lord.  It is an explanation of the significance of this particular neurotransmitter.

Antipsychotics are given to reduce the positive symptoms of psychosis, delusions, hallucinations, disordered thinking -- dopamine gone awry.  But messing with neurotransmitters is a tricky business.  They always do more than what we intend to control.  So antipsychotics can make the negative symptoms of schizophrenia worse, that sitting on the sofa, unable to speak or even move except to stuff your face with Cheetos until you explode thing that is so unattractive.

Raging delusional states or living dead.  Searching for the knife's edge between the two.  God help us.

Researchers at the Universities of Ontario and Western Ontario conducted a study similar to the one cited above.  They gave AMPT to people with a diagnosis of schizophrenia who were off their meds, measured symptoms and side effects, and did SPECT brain scans.  It turns out, some people are more susceptible than others to the soul-sucking effects of these meds.  About a third of people with schizophrenia have fewer dopamine receptor cites on their neurons and also experience these more extreme side effects.

Professor Lupin told Harry the issue is past trauma.  Harry, who watched his parents murdered when he was a baby, and survived a murder attempt on his own life, then later was raised with the daily abuse of his unwilling foster family, passes out when dementors approach.  Ron Weasley, whose parents you'd trade your health insurance for, reports, I felt like I'd never be cheerful again.  I don't know of JK Rowling got her science right -- haven't found research yet on the relationship between trauma and dopamine receptor cites.  Anybody out there know anything about this?

Anyway, here is a modest proposal:  Before any psychiatrist or scientist be permitted to preach or publish on the subject of medical noncompliance and transference, noncompliance and lack of insight, noncompliance and lack of education or cultural conflict or stigma or attachment theory, noncompliance and whatever nonsense, he/she should be required to undergo the same protocol as medical student Mr. A did.  

Like, then try writing the paper while under the influence of the medication.

According to Professor Lupin, chocolate reduces time to recovery.  So the lab might want to put in a stock of the good stuff before running this experiment, if the publish deadline is looming.

There seems to be a post on dopamine and chocolate in Prozac Monologues' future...

flair from facebook


2 comments:

  1. Word.

    Too many pdocs are willing to prescribe regimens they've never experienced and can never imagine experiencing. If they did, I think a lot of the "noncompliance" BS would evaporate ... as if by magic.

    JK Rowling amazed me with her description of the Dementors -- including their banishment by means of chocolate. When I first started experiencing a mood/energy dip during the late afternoon, my pdoc suggested trying dark chocolate. That's when I decided to keep him :)

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