Transcript Psilocybin and Consciousness

Psilocybin and Consciousness
Andy Alexander, Zane Andre
Albert Anaya, Dan Lotz
COGS175
Dr. Pineda
March 12, 2008
Presentation Outline
Introduction and History of use (Dan)
Chemical properties and physiological
mechanisms (Dan and Zane)
Alternate State of Consciousness (Albert)
Sensory Effects and Sustained Revelations
Conclusion (everyone)
(Andy)
History of Magic Mushrooms
 First documented use found in cave
paintings depicting the shamanic use of
mushrooms in what is now North Africa
 Mayan and Aztecs relics have also been
found depicting the ritual use of
hallucinogenic mushrooms
 In the Aztec culture these mushrooms
were known as teonanácatl or God’s flesh
Psilocybin
 Psilocybin is the
psychoactive
component of
mushrooms
 Classified in the
tryptamine family
because of the indole
ring
 Other tryptamines;
DMT, Melatonin,
Serotonin, tryptophan
and LSD-25
Psilocybin continued…
 Psilocybin is converted to the
psychoactive metabolite Psilocin.
 Psilocin is a partial agonist at the 5-HT2A
serotonin receptor in the brain
 Psilocin is also an agonist 5-HT1A and 5HT2C receptors
Psilocybin
Psilocin
dephosphorilization
Other Psychoactive Compounds
 Two other psychoactive chemicals are present in many species of
psilocybe-containing mushrooms: Baeocystin and Norbaeocystin.
 It is important to note that while these are minor compounds to
Psilocin, a dosage as little as 10mg is reported to elucidate effects
 These chemicals have not been the subject of any major research,
and consequently no detailed information is available on them.
 It is known, however, that they are also
Baeocystin
Norbaeocystin
Indole Ring
 The indole ring is chemically known as a benzene ring fused to a nitrogen-
containing pyrrole ring, and can contain be found in many aromatic
compounds, such as orange blossom scent.
 The indole ring makes up the primary structure of serotonin and tryptophan,
and is also found in LSD, DMT, Psilocybin, Psilocin, Baeocystin,
Norbaeocystin and many other hallucinogenic compounds.
 It is theorized that the binding mechanism of these type of psychoactive
compounds is based on this chemical shape fitting the ‘keyhole’ of specific
serotonin receptors.
 Because they are not chemically identical to serotonin, they have manifest
varied effects, particularly at the 5-HT2A receptor.
Indole Configurations
Psilocin and Altered State
 Corticol-thalamic pathway modulation
 Hyperfrontality
Psilocin and Altered State (cont.)
 Decrease in alpha and increase in beta in
the neocortex
 Prepulse Inhibition
Psilocin and Altered State (cont.)
Comparison between Dietrich and
Vollenweider
•Study between druginduced ASC and
placebo
•Same corticalsubcortical
organization
•Frontal-parietal,
temporal, and
occipital cortex,
striatum, and
thalamus
•Frontal-parietal and
striatal network
General Effects
 Duration (orally ingested)
 Total duration: ~4-7hrs
 Onset: 15-60min
 Plateu: 2nd to 4th hours
 After effects:
 Headache
 In general, no physiological hangover/ day after
effects
Sensory Effects:
Visual Hallucinations (VUS subscale)
– Visionary restructuralization
Illusions/ hallucinations
synaesthetic phenomena
Enhancement of percepts
– Contour distortion
– Increased sensitivity to light
– Closed eye visuals
Auditory hallucinations
Alterations in perception of time and space
Sensation of buzzing in the peripheral limbs
Recollective/ analytical stage
Attribution of salience to random objects/ events
Affective States
Increases in:
– Oceanic Boundlessness Scale
Measures derealization and depersonalization
phenomena
Associated with a basic positive mood state
–
–
–
–
Heightened feelings to sublime happiness (euphoria)
Grandiosity
Alterations in sense of time and space
Giggling, giddiness, increased emotional sensitivity,
sleepiness
Affective states…
Increase in:
– AIA scale (dread of ego-dissolution)
– “Measures thought disorder, anxious egodisintegration, loss of control over body and thought,
and derealization phenomena associated with arousal
and anxiety.”
Comprises: intense feelings of fear, nausea, mild to severe
anxiety, confusion, can precipitate or exacerbate existing
mental disorders (i.e. schizophrenia), working memory
disruption
– Similarities between psilocybin-induced psychosis
and early stages/ mild schizophrenia…
Psilocybin-induced psychosis provides clues as
to the physiological mechanisms of
Schizophrenia
“Psilocybin induces schizophrenia-like psychosis in
humans via a serotonin-2 agonist action” Vollenweider et al. 1998
– Administered psilocybin to three groups who were pre-treated with
5-HT2 antagonist ketanserin, 5-HT/ D2 antagonist risperidone, or D2
antagonist haloperidol
Results:
– Pre-treatment with either ketanserin or risperidone dose-dependently
blocked psilocybin-induced psychosis on APZ-OAV scale
– Pre-treatment with haloperidol only reduced the effect of psilocybin on
the OSE subscale, no influence on psilocybin-induced visual
hallucinations
Haloperidol uniformly increased the AIA scores in all of the subjects treated
with psilocybin
– Also found that Psilocybin increased the RT on memory-guided delayed
response task during peak effects of drug (evidence of impairment of
working memory)
Analytical/ Recollective Stage, Mysticism
and Sustained Revelations

the Good Friday Experiment, Pahnke 1963
 Theological seminary students received either 30mg psilocybin or 200
mg of nicotinic acid in a group setting during a religious service
 Participants who received psilocybin showed significant elevations on
the Pahnke Mystical Experience Questionaire
 Reported positive changes in attitudes and behavior at 6-months and at
a 25-year follow up
Analytical/ Recollective Stage, Mysticism and
Sustained Revelations
 “Psilocybin can occasion mystical-type experiences having
substantial and sustained personal meaning and spiritual
significance” R.R. Griffiths, 2006
 2006. administered psilocybin or methylphenidate in double blind study to
36 adults in a personalized, comfortable setting.
 Subjects told to focus on spirituality, "look-within," strive for mystical
experience
 67% of the volunteers rated the experience with psilocybin to be either the
single most meaningful experience of his or her life or within the top 5 most
meaningful experiences
 Sustained revelations
Continued…
 Evidence of sustained revelations:
-family and close friends reported noticeably positive
behavior and attitudes on subjects up to 2 months postexperience
- longer follow up is in progress
Conclusion
 Frontal-parietal activation might be where
conscious is altered.
 Capacity for sustained alterations of
consciousness sets psilocybin
experiences apart from other
hallucinogens
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References
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