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Brain Scan of Stroke Survivor
As a writer, my passion for the last five years has been to explain
Chinese medicine to regular people. I'm on the verge of publication
of my first full book on that topic.
As a thinker, one of my biggest curiosities is about how Chinese
medicine can be explained in terms of Western medicine, and how
Western medicine might be clarified or interconnected by Chinese
medicine. This is one reason I'm preparing to go to medical school
in 2006.
The first thing I learned about that stimulated my interest in
this area was Zang-Hee Cho's experiments with acupuncture and
PET-scans of the brain (I've described this elsewhere).
Then, while writing other articles, I made many forays into the
vast wilderness of PubMed, the National Library of Medicine's
database of millions of abstracts of scientific research. On one
such journey, I found another interesting integrative connection…
Strokes, Difficulty Speaking, and Acupuncture
After a stroke, some people have difficulty speaking. This is
called aphasia. It may be due to an inability to control the muscles
of speaking (the tongue and/or muscles of the jaw), or the stroke
may have damaged the language centers of the brain.
The first study I ran across on this topic was a 2003 University
of Hong Kong fMRI study of acupuncture on 17 healthy males.(1)
The acupuncture points stimulated were San Jiao 8 (SJ8) and Du15,
both of which were called "language-implicated acupoints."
This may have been a reference to other research on the effect
of these acupoints on the brain's language centers.
Traditionally, SJ8 is said to improve conditions of the throat,
(and perhaps by extension, the vocal cords), and Du15 benefits
the tongue, treats muteness, treats flaccid tongue, loss of voice,
and stiff tongue with inability to speak.
In the experiment, the Hong Kong researchers stimulated one or
the other acupoint with electricity (it doesn't state that they
needled them as in typical electroacupuncture, so it may have
simply been a TENS, or transcutaneous electrical stimulator).
They report getting the same brain activity results on the fMRI
from either point.
The brain activity from these points was in the "right inferior
frontal gyrus and in the left and right superior temporal gyri.
Nevertheless, no activation was seen in the left inferior frontal
gyrus." The reason they thought it significant that there
was no activation in the left inferior frontal gyrus was that
this is the side where normal speech originates. (ERROR corrected
from print version) Normal "syntactic and semantic processing"
activates the inferior frontal gyrus on both sides. (2) The Hong
Kong researchers concluded that, "although (their) results
support the notion of acupoint-brain activation, applying acupuncture
at SJ 8 or Du 15 does not activate the typical language areas
in the left inferior frontal cortex."
Seemingly, they were baffled by the results, and went no further
with their investigation. But I wondered, why would they get results
atypical of normal speech from points that should restore normal
speech? I also wondered when else this strange grouping of three
brain areas would become active. So, I searched PubMed for that
information.
Not coincidentally, I found a study of how the brain compensates
for how strokes impair normal language operation.(3) They found
that stroke survivors with aphasia who recover language ability
use the exact areas of the brain activated by acupuncture in the
other study. As they said, "these differential activation
patterns suggest a hierarchy within the language-related network
regarding effectiveness for improvement of aphasia; ie, right
hemispheric areas contribute, if left hemispheric regions are
destroyed."
This aphasia study had nothing to do with acupuncture. It's possible
neither group of researchers knows the others' research exists.
Each contained a piece of the puzzle. The picture formed by both
pieces suggests that acupuncture could increase the ability of
aphasic post-stroke patients to recover normal speech.
Of course, more research should be done to compare two groups
of stroke survivors- we need a study that compares an acupuncture
group to a control group. In the meantime, clinicians can add
acupuncture to the stroke recovery regimen.
References:
- Li G, Liu HL, Cheung RT, Hung YC, Wong KK, Shen GG, Ma QY,
Yang ES. An fMRI study comparing brain activation between word
generation and electrical stimulation of language-implicated
acupoints. Hum Brain Mapp. 2003 Mar;18(3):233-8. This is not
a large group, and wouldn't be sufficient for an RCT, but for
a mechanism study like this, it is enough to establish a pattern.
- Ni, W., Constable, R.T., Mencl, W.E., Pugh, K.R., Fulbright,
R.K., Shaywitz, S.E., Shaywitz, B.A., Gore, J.C., Shankweiler,
D. An event-related neuroimaging study distinguishing form and
content in sentence processing. Journal of Cognitive Neuroscience
12 (1), pp. 120-133. 2000.
- Heiss WD, Kessler J, Thiel A, Ghaemi M, Karbe H. Differential
capacity of left and right hemispheric areas for compensation
of poststroke aphasia. Ann Neurol. 1999 Apr;45(4):430-8.
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