Ive been experiencing now for about 7 years what i like to reffer to
as brain tingles.  Now while what I have to say might make me sound
like a parinoid dillusional i would rather not focus in on that
aspect.  Back seven years ago i had taken 8 tabs of LSD unknowningly
of the dosage.  I had what was commonlly reffered to most as a bad
"trip" to sum it all up, this was a life altering event that led to my
unevitable stoppage of ilegal drug usage.  I'm now suffering from
consipiracy issues and what the docotors say is to be schizo effective
disorder.  I, happen to beilieve that this is all just a government
coverup, regardless.  I have made several attempts to find out what
kind of experiments where done with lsd by the government back in the
60s and 70s but ran into many roadblocks during my research, my father
worked for the governemnt and as he knows of my condition i do believe
he had played a role in all of this.  I now suffer from these mind
tingles, they happen all over my brain including the stem and all
lobes. they seem to be either triggered by certain Pictures or
intuitive feelings, almost like a "spidey sense" and are to so degree
of a fair warning to pay attention to whats at hand. I don't know why
this has happened, nor if the LSD has anything to do with it,  I did
follow the "path" into the United State Military as i "saw the night
of my trip the next 4 years of my life unfold in my eyes" including
the departure into the United States Marine Corps.  I was only there
for a week and was discharged with many weird detailes to offer. since
then my life has been bound by rules and regualtions that "supposedly
only exsist in my mind"  and these brain tingles that no doctor nor
any reasearch i can conduct leads me to any kind answer. Does anyone
know this to be a typical side effect, or when i was younger that
scare on my forhead that was me supposedly cracking my skull ......
that i dont recall doing, was it something more to do with ....well,
you know use your imagination..

Zyprexa defficiency?

no, not zyprexa dyficency, but thanks for the moronic comment. 
Zyprexa is actually a shitty drug with a low success rate in treating
schizophrenia, and  on behalf of myself and anyone else who has been
prescribed this horrible drug, having it banned for its horrible side
effects would truely be a Godsend.

Yeah, that amount of LSD screwed you up. LSD causes significant
psychedelic effects with as little as 25 micrograms (less than what
you would get licking a laced postage stamp). (LSD is 3000 times more
potent than mescaline.) Your feelings of conspiracy, etc., are classic
signs of schizophrenia, most assuredly not caused from hitting your
head, but rather from the LSD, since LDS has been shown to lead to
psychotic disorders. I'm not really sure WHAT you think is a
conspiracy though. The government, just like everyone else, knew that
LSD was not good. It's not like the government forced you to take LSD
or anything. If you want to know what research has been done on lsd,
just look at old NIH grants, or look up on medline:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi where you will find 132
pages of research abstracts (quite technical though).

The effects of lsd include hallucinations, mood changes such as
elation, paranoia, and depression, intense arousal, sometimes even a
feeling of panic. Pupils dilate, bp and heart rate increase, flushing,
salivation, lacrimation, hyperreflexia, etc. The panic, anxiety, and
depression are all included in the "bad trip."

LSD is known to bind to all types of serotonin receptors on neurons in
the brain (also called 5-HT receptors). This includes the type 2
serotonin receptor, which is the same type of receptor that has been
found to be abnormal in schizophrenics. Serotonin receptors are also
the target of antidepressant drugs, as well as other things.

LSD, unlike pretty much any other drug, is actually well tolerated by
the body (in terms of metabolism, etc.). There have been no documented
fatalities from lsd overdose (although many cases of suicide and
accidental deaths from doing crazy things), which explains why you
didn't die from that much lsd. However, the effects of lsd are known
to last a lifetime, including paranoia, flashbacks, and visual
disorders, all of which can be triggered by mere stress, fatigue,
darkness, marijuana, other neuroleptics, and anxiety. So, what I have
to say to you is that you messed yourself up, but don't stress about
it. What's done is done. You may feel like there's some conspiracy or
something, but I promise you there's not. Your mind is just going
nuts. But try to get a grip on things. You can still live a good life.

I'm not a doctor, nor am I a google answers researcher. The answer
below is information obtained from web searches.

That being said - From your post, it seems that you have already
consulted with doctors about the symptoms that you've described.

Your description of brain tingles is similar to how some people
describe seizures. However, there are other things that can cause
similar sensations, including side effects from medication.

More information on epilepsy and seizures is available on this site:
http://www.epilepsy.com/epilepsy/main_epilepsy.html

Such symptoms do *not* appear to be a common long term side effect of
LSD usage, however.

There does appear to be a link between LSD usage and schizophrenia, in
people with a predisposition to it in the first place.

Please see this article for a more detailed answer on the connection
between the two: http://www.mhsource.com/expert/exp1121498a.html

Also, this article http://leda.lycaeum.org/?ID=8832 details some
studies done on the matter.

Some more information on LSD accelerating the onset of schizophrenia
is available on this page, under "DIFFERENTIAL DIAGNOSIS" -
http://www.vh.org/adult/provider/psychiatry/CPS/28.html

For more information on other possible causes of schizophrenia, please
see this article:
http://mentalhealthcare.org.uk/schizophrenia/causes/

If this isn't the information that you're looking for, please clarify
the kinds of information / sources that you're seeking.  No one, even
a doctor, is going to be able to diagnose you online. You're going to
need to see a neurologist in person for that. We can provide you with
more information on Schizoaffective Disorder, treatments, and support
groups; more information on (publicly available) studies on the
effects of LSD; and / or information on how to file for documents
under the Freedom of Information Act.  Would any of these be
considered an acceptable answer to your question?

I also wanted to mention from up above that yes, zyprexa will have
many side effects because it not only targets serotonin receptors, but
also muscarin, dopmine, and histamine receptors in the brain. Also,
more importantly, I forgot to actually answer your question. The brain
has no sensory receptors. This means that the brain itself cannot feel
touch, pain, etc. (which is why they can do open brain surgeries
without anesthesia). So the tingles you feel either come from the
meninges which surround the brain, or from the skin, or it may be a
type of parasthesia, where your brain thinks it's feeling something
there, but there's really no sensory info coming from that area of the
body. I'm trying to remember which drug it is-- cocaine I believe--
that can make you feel like there are bugs crawling on you. This is
that sort of thing. Anyway, it is likely an extension of the effects
that I wrote of above. Hope that helps.

Sorry, I forgot to document my source-- all the info I put up above
can be found in Goodman and Gilman's "The Pharmacological Basis of
Therapeutics," and can be confirmed by the medline "lsd" search I
mentioned (or search for lysergic acid diethylamide), as well as many
other on-line resources.