
Brain scans reveal how LSD affects consciousness - etiam
http://www.nature.com/news/brain-scans-reveal-how-lsd-affects-consciousness-1.19727
======
omginternets
I'm a Ph.D student in Cognitive Science and I'm currently writing my
dissertation on the topic of conscious perception.

I think this study is pretty damn interesting because the cingulate cortex
(ACC & PCC) along with the thalamus are implicated in states of consciousness
(i.e. wake/sleep/coma/vegetation/etc) and also in "access consciousness"
(i.e.: “consciousness” in the sense of “I am conscious ​ _of_ ​ such and
such”). Subjects dosed with psilocybin have decreased BOLD (blood-oxygen
level-dependent) signals in these regions.

BOLD signal essentially tells you how active a brain region is (the more
active the region, the more energy it needs, so the more irrigation it
requires), so this tells us that the thalamic and cingulate regions are
relatively suppressed by psilocybin.

This is congruent with a longstanding (albeit simplistic) theory on how
hallucinogens work. The idea is that hallucinogens would actually be
inhibitory in their function, but they would selectively inhibit regions that
are, themselves, inhibitory.

So in a hand-wavy way, you can think of the ACC as keeping imagination in
check. It inhibits perceptual areas (that are also activated by imagination)
so that when you imagine a tiger, you don’t actually ​_see_​ a tiger. With
psilocybin & LSD, this function is suppressed so you see the tiger.

Again, I'm simplifying to the point of risking a collective beat-down from my
colleagues and lab-mates, but I thought it might help illustrate what's groovy
about this study.

~~~
mettamage
I forgot where I read the idea but some neuroscientists proposed that
consciousness in the brain is more a measure of interconnectivity of activated
brain regions. Basically, whatever brain region communicates with each other
allows for mixed matching, whatever that brain region does (synesthetic people
are very concrete examples of this).

What do you think? Could this be true?

I find it interesting to consider but have a hard time understanding how the
brainstem fits into this.

\-- psych. & computer science student with a strong interest in cognitive
science & neuroscience

~~~
Balgair
Continue your passion! Neuro is so cool and we need comp-sci people, at the
least to process the data and help out with connecting VGA cables (I shudder
at bio people's hard-coding).

Interconnectivity in the brain is very stereotyped. Certain areas typically
only talk to certain others. The 'connectome' in the brain is being mapped
these days and there is a lot to learn, but I think we can say that the
connectome is stereotypical. That's good, we can make a road map then!

Consciousness is a tougher nut to crack, though. Many questions arise from
disease studies like this one:
[https://www.newscientist.com/article/dn12301-man-with-
tiny-b...](https://www.newscientist.com/article/dn12301-man-with-tiny-brain-
shocks-doctors/) . Obviously from that patient, he lives a normal life (within
the IQ standard deviations) and no-one else saw deficits in him worth concern.
Other patients report only balance issues and delayed speech with having half
of all the body's neurons not develop:
[https://www.newscientist.com/article/mg22329861-900-woman-
of...](https://www.newscientist.com/article/mg22329861-900-woman-of-24-found-
to-have-no-cerebellum-in-her-brain/). Still other people have extreme deficits
in short term memory from having comparatively small portions removed :
[https://en.wikipedia.org/wiki/Henry_Molaison](https://en.wikipedia.org/wiki/Henry_Molaison)
.

What I am saying is that the brain is a confounding mystery and we need the
help of people in comp-sci. If you have the time, try to volunteer at your
local university, we need the help.

~~~
stuxnet79
> Continue your passion! Neuro is so cool and we need comp-sci people, at the
> least to process the data and help out with connecting VGA cables (I shudder
> at bio people's hard-coding).

What do you mean by the connectome is stereotypical? I was reading up on
connectomes and was pleasantly surprised to find out that model organisms like
C Elegans have been fully mapped but I haven't heard of any large insights
being derived from this.

In general what are the computational stumbling blocks in Neurosci at the
moment? (I have a genomics background)

I'd like to do a Phd in Cog Sci or Neurosci (computational) but I've been so
stress free ever since moving to industry (from academia) 10 months ago I
can't really see myself going back for the long haul.

~~~
Joof
About the stress of academia...

I did some work with a cognitive science / computer science researcher while
in undergrad and know plenty of PhDs in various fields. Academia is seeping
with stress. Grad students have a very high rate of mental illness. I greatly
admire the people who do that work, especially if they are working towards
tenure. The work is incredibly fun, but you have to be a certain kind of
person to handle the tenure route.

~~~
stuxnet79
So did you stop at the Bsc level or did you go ahead and do a Masters? Tenure
is basically not worth it to me. If I went back to grad school I'd go with the
intention of moving right back to industry afterwards. While I don't miss the
constant stress I do miss the challenge, progression, joy of discovery and
relative independence of Grad School.

------
justsaysmthng
LSD and psychedelics are the next frontier in science IMHO. And I don't mean
just neural science, psychology or psychiatry.

It seems that these substances hold the key to how the brain "produces"
reality and that could open doors to areas such as computer-brain interfaces,
transfer of consciousness, fully immersive "life-long" virtual reality and so
on. But that's just peanuts.

There's the social aspect - psychedelics have had a strong influence on
millions of people when they became popular in the '60s, shifting their
worldview, which in turn lead to new directions in music, art, film,
literature, science and society in general.

Then there is the "ecological" aspect. Many people report "feeling one" or
"connected" to everything including other living beings when tripping on
psychedelics.

That metaphor persists after coming down and many people become aware of their
place in nature, what they eat, how they treat animals and plants and
eventually other humans. "Flower power" might just be what's necessary to curb
humanity's most stringent problems, such as "climate change".

"Make love not war" hippy slogan will also help given how armed the world is
right now. I would add "use condoms !" to it though - there's too many of us
here already! :).

The MRI images are a confirmation of the "mind expanding" term used so often
in conjunction with these substances.

Maybe "mind expansion" is what's needed in order to combat the "mind
shrinking" that is so beneficial to the few, who, with their ignorance and
greed, are about to run this ship into the ground.

I'd love to see more research, a lot more research with these substances.

Understanding these links is very important, because right now there is a new,
larger, global wave of psychedelic use which is unprecedented.

~~~
MrBra
If you guys want to start soft with some small dosages of mdma at home, I
definitely recommend you to spend some time watching Daft Punk videos on
YouTube, you won't regret that! It will a be somewhere in the middle between
sweet, smooth, nice and brainfucking! You won't forget the music and the mood
for long...

------
nefitty
Pretty cool. I'd like to point out that meditation might have a similar
dampening effect on the default mode network as well.
[http://www.ncbi.nlm.nih.gov/pubmed/25904238](http://www.ncbi.nlm.nih.gov/pubmed/25904238)

The question arises again, can psychedelics have lasting effects or is
meditation the only way to create permanent positive change in that direction?

Finally, a quote from a letter to Osho: "Many people are experimenting with
the drug ecstasy. I heard you say once that a lie is sweet in the beginning
and bitter in the end, and truth is bitter in the beginning, and sweet in the
end. I have been meditating, but I don't have the experiences people report
from the drug ecstasy. Is the drug like the lie, and meditation the truth? Or
am I missing something that could really help me?"

~~~
lossolo
I did ecstasy and i did LSD. Ecstasy is like a lie in this quote comparison.
You get high in the beginning and it brings you down at the end, really awful
feeling at the end. LSD is different, i experienced world differently even for
couple of days after i took LSD. World seemed different. I knew what was
important in life and what not, very clear.

I can't describe how you feel on LSD, and people that didn't took LSD or
ecstasy are not aware what their brain is capable off.

When i first took ecstasy i didn't believed that you can feel that way. So
different from alcohol, weed. You feel love. LSD was even weirder experience.
On LSD you can shape reality, you can feel reality so well, like you are part
of it, connected. I saw snail on the road, everything was blurry around him,
but he was visible, so sharp, i could feel him as part of me, connected, in
this journey called life.

Everything was so obvious, answer for question "why?" was known, even if i
couldn't say it out loud, i could feel that answer for this question was
somewhere in my mind, but i just couldn't access it. Feeling that it's there
made everything clear, i felt peace.

Everything that i did in life before and what i would in future seemed such
trivial and not important. That connection with reality, understanding
different forms of it, changed me. I feel like LSD can give you answers,
answers for questions that you would not find without it.

~~~
lsd_throwaway
For a counterpoint to this - I decided to do 150 micrograms of LSD after
reading a lot about it on HN, talking with many friends that had tried it or
do it fairly regularly and reading as much as I could find (Sam Harris,
Huxley, What the Dormouse said etc.).

Nothing can really prepare you for it - the dream like state, the visuals and
just the capacity of how different things can be. When looking at things I saw
them shift, it felt similar to those computer vision machine learning videos
from google. As if I could see my vision attempting to resolve images into
objects that fit their parameters. I felt like I got some insight into how
consciousness works by messing with it.

The trip itself was mostly pleasant - the next day and several months were
not.

The next day I couldn't stop pacing, couldn't relax - kept hyperventilating. I
couldn't eat either, basically kept having panic attacks. Over the next few
weeks I felt outside of myself - like it was weird to be alive and in a
person. I was terrified that I was going schizophrenic or losing my mind. I
thought I might have a psychotic break. All of this paired with
insomnia/general sleep disturbances (which scared me too). I thought I might
have to stop working, I had anxiety with real physical effects (headache, lack
of appetite, extreme fear). Even watching TV was difficult/overwhelming.

I had serious existential fear about dying and the inevitability of my family
dying (and still do to some extent) - sometimes feeling that everyone else is
insane for not being afraid.

I didn't end up taking SSRIs, but I did tell people and got help - it's about
seven months later and I feel mostly better.

I'd caution people against trying it.

~~~
throwaway163
I had a similar experience. Except it was caused by marijuana.

It sounds like a classic case of Depersonalization disorder, which is a
subset/interconnected with anxiety. Google it.

The consensus is that it can be triggered by substances in approx 3% of the
population. Weed, mushrooms, ectstacy and LSD are the most common culprits.
It's extremely common, though it has very little mindshare among mental health
professionals. Probably because there is no pharmaceutical treatment.

It took me about 2 years to get back to reality after my trip. I'm still not
quite the same. But I'm thankful for the experience because it's been the
hardest thing I've experienced and I've learned a lot about myself, self care
and the importance of relationships

Good luck sailor!

~~~
throwaway102942
I tried marijuana and my experience with it was a lot more like what my
friends and you describe LSD or similar drugs to be like. Before marijuana I
already had mild hallucinations and I was diagnosed with schizophrenia from a
mild psychosis. It's definitely made my existing hallucinations much stronger
even years after smoking.

For me the general feel of the trip was as if some sort of filter had been
removed so you get to experience things you probably shouldn't experience.
This includes experiencing experiences (fractals). What we experience tends to
be individual so I won't go into that. But you get a wider eye view, motions
are more defined, shapes are more defined, etc. It's like a burn in effect (in
an image editing sense) but applied to other senses as well.

My favorite was probably not being able to determine the size of objects (or
that it would fluctuate) which made sitting in front of a computer like
sitting in a gigantic room with a gigantic tv.

It was a bit uneasy after the trip at first but I got used to it quickly. I've
already had similar experiences but of course not as strong.

In my experience with all of this so far the best tool for me is being
skeptic. My only fear is that I'll lose the ability to reason forever, which I
have already lost in short bursts here and there.

~~~
ethanbond
I'm immediately skeptical of people who claim to have felt "similar" effects
to LSD without LSD, but that's a pretty interesting scenario involving weed
(how much?!) and schizophrenia. No clue how close you could get to emulating
it, but it sounds like at least a few of the common effects of an acid trip.

~~~
soundwave106
There does seem to be _some_ links between the endocannabinoid system (the
primary target of marijuana) and the serotonin system (the primary target of
LSD). EG:

[http://www.ncbi.nlm.nih.gov/pubmed/17944876](http://www.ncbi.nlm.nih.gov/pubmed/17944876)
[http://www.jneurosci.org/content/27/43/11700.abstract](http://www.jneurosci.org/content/27/43/11700.abstract)

From what I can see, the relationship isn't terribly clear at this time. As
dopamine and serotonin systems are linked to schizophrenia, until more is
known, I personally think anyone with even mild signs of schizophrenia would
do best to avoid chemicals like marijuana, LSD, stimulants, etc.

------
CitizenKane
Very fascinating continuing research!

This group has been doing a number of studies on psychedelics and this is not
their first rodeo.

You can see some of their previous research here
[https://www.researchgate.net/publication/267512525_Homologic...](https://www.researchgate.net/publication/267512525_Homological_scaffolds_of_brain_functional_networks)
(PDF) which talks about the brain under the effects of Psilocin, which is the
active chemical which comes from Psilocybin Mushrooms.

It's a fascinating area of research, and I've found it surprising how few
drugs are actually examined in this manner. The lack of rigor that goes into
the law with regard to drugs is deplorable.

------
jdpigeon
Finally some good research on LSD in humans.

Very interesting finding about the increased connectivity to the visual
cortex. It certainly vibes with my anecdotal experience -- the whole visual
world just seems more meaningful and 'in focus'. Tripping in an art gallery
can be a real treat :)

~~~
stevedekorte
I tried that at the Van Gough museum but got creeped out at seeing everyone
ignoring each other and staring at walls and had to escape to a nearby park.

~~~
de_Selby
Sounds like a pretty normal art gallery experience then.

------
neurobuddha
That is the most "lit up" MRI scan that I've ever seen. Obsessive compulsive
people have highly activated brains, and I know musicians activate many parts
of the brain - but not like this.

~~~
matthewwiese
Interesting comment on OCD, given that I have the disorder. Could you link me
a source for that claim? Many friends of mine study neuroscience so I'm
inadvertently becoming more interested as an amateur.

~~~
neurobuddha
This scan shows glucose metabolism vs "normal":
[https://www.pinterest.com/pin/264445809342542302/](https://www.pinterest.com/pin/264445809342542302/)

------
techload
Interesting also the linked study on Psilocybin, which seems to decrease
activity among brain hubs:
[http://www.pnas.org/content/109/6/2138.full](http://www.pnas.org/content/109/6/2138.full)
"Psilocybin caused a significant decrease in the positive coupling between the
mPFC and PCC. These results strongly imply that the subjective effects of
psychedelic drugs are caused by decreased activity and connectivity in the
brain's key connector hubs, enabling a state of unconstrained cognition."

------
jarmitage
I backed this study on Walacea, you should check it out if you're interested
in this research getting funded whilst governments etc play catch up

[https://walacea.com/](https://walacea.com/)

Edit: watch out for this study's results soon:

[https://walacea.com/campaigns/dmt/](https://walacea.com/campaigns/dmt/)

------
stared
See also how brain connectivity gets changed by psilocybin (magic mushrooms):
[http://mindblog.dericbownds.net/2014/12/psilocybin-
changes-b...](http://mindblog.dericbownds.net/2014/12/psilocybin-changes-
brain-connectivity.html) (and the actual paper:
[http://rsif.royalsocietypublishing.org/content/11/101/201408...](http://rsif.royalsocietypublishing.org/content/11/101/20140873)).

In short: you get more long-range correlations, so the perceived synesthesia
may have very "hardware" basis.

------
payamb
For me LSD & Mushrooms were eye opening experience, I was born in a huge city,
I grow up far away from nature, surrounded with cars, Millions of people .

I think psychedelics opened my eyes to nature, To what we were created from,
We are a part of that but today we are so busy progressing in our careers,
Buying bigger house and saving more money we ignore our real nature.

Earth is not just ours, Its home to million of other creatures that we ignore
to see, Its what feed us and there are a lot of amazing secret living there.

I believe in third eye. and i believe psychedelics opened that third eye for
me.

------
Mahn
I spent an hour reading this thread and I still have no idea whether I should
try it or not. I always leave confused when I read about LSD, as if it's both
amazing and horrible.

~~~
johnthedebs
As someone that's done it (a dozen or so times), I always read these threads
and feel confused about whether I should recommend it to other people. I
usually do recommend it, though, with plenty of caveats.

It can be an incredible experience if only for the shift in perception that it
causes. It makes you see that the way your mind operates day-to-day (through
highs, lows, and in-betweens) does not even come close to the range of
experience that's possible.

It can be euphoric, and it can be scary, and depending on your predispositions
it can probably improve your life significantly (given that you integrate
insights from your experience into "normal" life), or really mess with your
head (esp. if you have latent schizophrenia or similar - I'm admittedly pretty
ignorant about this so obviously do your own research).

Anyway, my recommendation to people using it for the first time is to start
with a low dose (you often won't even realize it's having any effect until
after the trip is over – I didn't believe it my first time), make sure you are
in a safe place where you can be left alone to relax if you need to, and
ideally make sure to have someone with experience & that you trust to spend
time with you and guide the trip.

Also, here's some recommended listening:
[http://fourhourworkweek.com/2015/03/21/james-
fadiman/](http://fourhourworkweek.com/2015/03/21/james-fadiman/)

------
TheOtherHobbes
This is sadly anecdotal because I can't find a reference online, but there was
a story a decade or two ago about someone who sold completely inert blotting
paper tabs at a festival.

No LSD, nothing at all. 100% placebo.

And people still tripped on them - to the extent that some of them came back
and wanted to buy more, telling him how amazing the LSD was.

Perhaps the science is a little less straightforward than it seems.

~~~
conceit
That's what hippies call the setting. That's literally what the hip in hippie
means to me, the ridiculous enthusiasm. I don't mean offense, but I find other
words for the kind of careful optimism that is necessary to keep this ignorant
excitement going.

That said, the article's link to the paper seems broken. Because there's no
correct link to the paper yet in this discussion, my impression that most
comments here don't really hold scientific merit gets stronger. I will admit
that I don't understand enough of statistics to judge the methods used, if
there was any control group at all.

------
keypusher
I used to work with fMRI scanners, and I would definitely not want to lay
inside completely still while tripping on acid for 8 hours. Interesting
results though.

------
caycep
there's also the new 5HT2a inhibitor, pimavanzserin...as a thought experiment,
what would scans w/ this medicine AND LSD onboard show?

~~~
tpm
A hint may be somewhere here:
[http://journals.plos.org/plosone/article?id=10.1371/journal....](http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0009019)

------
mavci
Fringe, anyone?

~~~
mavci
[https://www.youtube.com/watch?v=sTskUKq81MQ](https://www.youtube.com/watch?v=sTskUKq81MQ)

