are bits of writing from many sources such as personal correspondence,
posts to on-line discussion groups, notes, and occasionally even some journaling.
All of this is informal in nature, but contains some interesting and/or
in your brain
[Posted to the neuroscience
group on MySpace.com]
>Is this passage
telling me that there is a part of my brain that tells me that my "soul"
(so to speak) is inside my flesh and not inside that box of Swoops I'm
holding in my picture?
Not exactly. It's
just that you know where you are in physical space. Rather than the awareness
of this, people general speak in terms of the sensory component, something
called "proprioception" that monitors where your body parts are relative
to one another. This is why you can put your arm over your head and know
which direction you are pointing your index finger even though it isn't
in your field of vision (unless you look up, of course).
Then there are "place
cells" that keep track of where you are as a person. (I don't know if this
awareness has been assigned a term yet; there isn't an obvious sensory
component since this is achieved through vision whereas proprioception
is accomplished via mechanoreceptors in your muscles). These cells fire
up if you are in, for example, the corner of a room vs. the center of it.
No one has figured
out how higher levels of awareness arise that let us interpret these signals.
This is part of what consciousness is, and so far no one has even been
able to satisfactorily define that concept, let alone to formulate an operational
definition that would allow anyone to test hypotheses concerning the workings
However, if conscious
awareness of where you are equates to having a "soul," then a few stiff
drinks and you'll lose your soul. So the Baptists were right!
in the brain (cont'd)
[Posted to the neuroscience
group on MySpace.com]
>Is there really
a part of my brain that tells me that I'm sitting in the chair?
Yes. If you think/feel/sense/recall/etc.
something, there's a part of your brain that is involved in it (and since
most mental processes are multi-faceted, there is usually a system of parts
coordinated in that process; see also "association cortex").
Most functions can
even be localized with a high degree of specificity. Even the more general
mental processes like memory or consciousness (whatever that is) still
have a clearly physical basis as evidenced by the altered/reduced/eliminated
states induced by trauma, injury, drugs, tumors, surgery, electrical/magnetic
stimulation, or anything physical that touches them.
The fact that you
are aware of your brain chemistry and can observe it objectively makes
it an interesting phenomenon, so you appreciate its manifestation even
though are are affected by it on a separate level.
[Posted to the neuroscience
group on MySpace.com]
One of my professors
works with chronic pain using animal models. He admits that one of the
frustrating things about research in his area is that you don't really
know if the animal is indeed in pain. Unlike humans (who can at least use
subjective assessments like Likert scales, etc.), you can't just get an
assessment of the degree of pain to see if the phenomenon you intend to
study and treat is even present in the first place.
Until we get a firmer
grip on what an emotional or other cognitive state is in terms of neuroscience,
there will always be a degree of uncertainty in much of the research conducted
into problems like this.
[Posted to the neuroscience
group on MySpace.com]
>Has anyone here
heard about those who can't feel pain?
Yes. I have no idea
what this is called, though. Apparently, it's quite rare.
>Or that they have
a missing limb but it still feels like they still have it.
This is commonly
known as a phantom limb. It comes from retaining the internal representation
of the limb(s) and the fibers leading up to those representations (e.g.,
in the dorsal nuclei, thalamus, and, finally, in the somatotopic cortex).
Those areas are still activated and have a limb (so to speak) long after
the physical limb has been lost, although this does diminish with time
depending on a lot of factors relating to brain plasticity (e.g., the age
at which the limb was lost, etc.).
>Or that let's say
when they're shaving they feel it on another part of their body.
This is called referred
sensation. It's especially common for people to have referred pain, however.
For example, when someone is in the beginnings of a heart attack, they
typically feel pain in one arm. This is (thought to be) due to convergence
of fibers from two regions. Unfortunately, the brain often misinterprets
which region a signal is originating from, so you think the pain has a
different cause unless there is strong evidence to the contrary (which
doesn't change the actual sensation, of course).
I took a "brain
test." My scores were:
These were about
what I expected after the first few questions. I usually come out like
this on these sorts of tests. The L/R and Vis/Aud dichotomy is largely
redundant. The left side of the brain is responsible for language in all
but 1% of the population. In fact, I amazed the students in the lab I teach
the other day when I deduced that a student's grandmother was left-handed
based on the symptoms she experienced following a stroke (language difficulty
and left side paralysis).
about the brain test and testing in general
I didnít re-attempt
the test after the first time, but the comments were fairly accurate in
my case. The more extreme you are, however, the better the accuracy because
of what are called ceiling and floor effects. Once you reach a limit, you
canít compensate for the effects. The reason why this test can report on
people with a high accuracy is not so much because these questions tell
a lot about your personality, but because they tell a lot about the about
the way your brain is organized. From that, the leap into personality can
occur. There has been an enormous amount of research into this area as
organizations use it for placing employees in the best positions, etc.
Schools are beginning to employ personality tests and the like for the
purpose of finding the best means of assessing kids, the rationale being
that the more appropriate the test, the better the school will look in
terms of test scores.
An interesting extension
of this field is the area of emotion intelligence (EQ, as opposed to IQ).
This looks at people in terms of personal motivation, empathy, interpersonal
skills, etc. This touches on something I alluded to earlier with respect
to Robert Downey, Jr. and his infamous drug problems. All our experiences
and much of our personalities reside in the frontal cortex. However, the
pre-frontal cortex can over-ride intelligent decision-making and run a
life into the ground through poor choices (which, most importantly, run
counter to everything an individual may have been taught, believes, and
professes publicly). This is the next frontier in psychology and especially
with respect to pharmacology.
more about the brain test
C took the brain
test and scored mostly right brain/visual, which is not especially surprising
knowing her, but unusual given in her area of teaching. I probably mentioned
to you that "Auditory" is a misnomer for what they are testing for; this
test looks for language preference. Believe it or not, I tend to be more
language-oriented than in most areas. For example, she teaches English
mainly through literature, whereas the sciences often require very precise
(and certainly specialized) use of words; and I tend to do better than
average in this area. I drive my students crazy making revisions to their
lab reports, and used to proof anything anyone in my lab wrote.
There are a lot
of perceptual studies that show that people can pick up on little things
that aren't quite right. For example, if you are shown a photograph of
someone with the image reverse, you will notice that something is a little
off. Similarly, they can make a perfectly bi-lateral image by duplicating
one side of your face and flipping it. People look at those images and
can't place it, but they know there's something different. On the other
hand, I had a nose job and no one noticed. Go figure.
If you want to learn
about a real "sixth sense" we all have (no, not the dvd in your living
room), then you might want to read this article:
Brown JW, Braver
TS. Learned predictions of error likelihood in the anterior cingulate cortex.
Science. 2005 Feb 18;307(5712):1059-60.
Here's the abstract:
The anterior cingulate
cortex (ACC) and the related medial wall play a critical role in recruiting
cognitive control. Although ACC exhibits selective error and conflict responses,
it has been unclear how these develop and become context-specific. With
use of a modified stop-signal task, we show from integrated computational
neural modeling and neuroimaging studies that ACC learns to predict error
likelihood in a given context, even for trials in which there is no error
or response conflict. These results support a more general error-likelihood
theory of ACC function based on reinforcement learning, of which conflict
and error detection are special cases.
This story was carried
by a number of sources in the popular press when it first broke last February.
Here's a good one:
Also, Malcolm Gladwell's
latest book "Blink" deals with a lot of the rapid and completely unconscious
processing that looks to us to be intuition or something else paranormal
(Just to ruin it for you: No spirits were required). He's very readable,
and it's good stuff. There are sample chapters on his site as well.
>I'll probably get
the wisdom teeth taken out soon, though. :)
I didn't have a
bad experience with this at all. In fact, I has a good time on the gas.
I remember laughing at some really strange stuff that was going on. For
example, two of the nurses (assistants?) were talking. One was telling
a story about how she and her brother ran into one another at a wedding
the previous weekend and they were very cold to one another. For some reason
(okay, it was the gas), I thought this was possibly the funniest thing
I had ever heard, but I kept trying not to laugh because I wanted them
to continue with this "hilarious" story.
I also remember
looking down at my feet, only I couldn't see them since my head was pretty
far back in the chair. I looked down and saw the wall in front of me. Since
the wallpaper was vertically striped, I was really confused because my
show laces were horizontally striped, so what was going on? It finally
clicked that I was looking at the wall, and I started laughing again at
that. Fun stuff!
There is a mental
phenomenon known as PPI that most people have, but is lacking in people
with ADD/ADHD. Here's a (relatively) brief overview I wrote up for another
discussion group a while back. This is fairly technical, but give it a
read (all the way through this time, guys!). I think many of you will find
PPI (short for "Pre-Pulse
Inhibition") is a feature absent in a lot of mental disorders where afflicted
individuals have trouble filtering out intense sensory stimuli (e.g., loud
noises, bright lights). Some of these disorders include ADD/ADHD, schizophrenia,
autism (including Asperger's), and OCD, among others.
Where the name comes
from is that, in most individuals, a "warning shot" (i.e., pre-pulse) will
prevent a second, larger stimulus from making them jump when it arrives
moments later. For example, if I say "Boo!" you might jump. But if I say
"boo" (normal speaking voice) and then give you the big scare a second
later, odds are it won't spook you as much. This is not the case in individuals
with the disorders highlighted above, hence ADHD kids attend to the least
distraction, autistic individuals are bothered by physical contact and
deviations from routine, and so on. I'm sure many of you reading this can
think of examples of sensory stimuli that you could not filter out such
that it either became painful or at least intrusive enough to keep you
like having a hangover or some forms of migraines in which sensitivity
to stimuli is increased... only it's like that all the time. Some people
who have this to a large extent find that they are irritated by loud noises
and/or bright lights more than their peers. (I'm one of these people, incidentally.)
As for what you
can do about it... that's a tougher problem. If it is part of a larger
condition that can be diagnosed (e.g., ADD/ADHD), doctors can then treat
the big picture and (hopefully) deal with that component in connection
with the rest. However, there are certain modifications you can make yourself
like avoiding clubs with loud music (try a coffee house instead?) and carrying
a pair of ear plugs. That doesn't look cool, but if you're going to be
miserable otherwise, which would you prefer? I would also suggest explaining
what PPI is to your friends so they won't think you're being rude if you
have to distance yourself from unbearable stimuli.
That's hardly the
last word on the subject. I'm sure there is much better advice out there,
but this is a framework for understanding what you're dealing with.
Concerts don't bother
me so long as I have earplugs handy. If it is a constant level (albeit
a loud one) I can adjust. However, there's a neurologic ability most people
have that I don't: pre-pulse inhibition. "Normal" people can filter things
to a certain level after their first exposure, but I can't. It's a sensory
gating phenomenon, and it's one of the core things in autism than makes
this kids freak out when they are exposed to unexpected stimuli.
ADD/ADHD kids have
the same problem, although they are "driven to distraction" rather than
annoyance in most instances. That being said, extreme levels have the effect
on them that you usually see around me. I think my dad has the same problem
because he is bothered by a lot of the same sounds as I am, particularly
kids screaming spontaneously and unnecessarily. He and I both want to kick
them in the teeth when they pull that shrill, obnoxious shit while standing
right next to you.
Whereas most people
are just annoyed, it is not a very pleasant experience when you can't filter
it out enough to make it less than outright painful.
I know a lot of
people have "cosmic" experiences on LSD. I had one of those momentarily
as a result of sleep deprivation. This was when we were still lying in
Folsom, and I had been out all weekend camping with a couple of friends.
We stayed up all night running around the woods and riding bikes on the
highways (Statistically I should have been dead sometime in the early '90s),
so we never got any sleep. At one point we went over to the home of one
of my friends we were out with so he could pick something up. Since I was
all muddy, I laid down on the patio and was halfway asleep within seconds.
My eyes were barely open, and I saw a little string dangling down from
the cushion on the seat of one of the patio chairs. In my mind that string
was the most important thing in the universe. I couldn't tell you now what
the hell I was supposed to do with it or how to tap into its incredible
power, but it was the culmination of billions of years of work that would
save us all. Or something like that. I woke myself up laughing as I realized
what I was thinking lying half-asleep on a patio in Folsom all covered