Received: by alpheratz.cpm.aca.mmu.ac.uk id SAA18949 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-majordomo@mmu.ac.uk); Wed, 28 Nov 2001 18:49:26 GMT Date: Wed, 28 Nov 2001 13:43:56 -0500 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Subject: Fwd: Memories etch sense of self From: Wade Smith <wade_smith@harvard.edu> To: memetics@mmu.ac.uk Content-Transfer-Encoding: quoted-printable Message-Id: <E0ECDACE-E42F-11D5-86B0-003065A0F24C@harvard.edu> X-Mailer: Apple Mail (2.475) Sender: fmb-majordomo@mmu.ac.uk Precedence: bulk Reply-To: memetics@mmu.ac.uk
Memories etch sense of self
By Chet Raymo, Globe Staff, 11/27/2001
http://www.boston.com/dailyglobe2/331/science/Memories_etch_sense_of_selfP...
shtml
Neurologist Antonio Damasio suggests in his book ''Descartes'
Error'' that the great French philosopher got it backwards: Not
''I think, therefore I am,'' but rather ''I am, therefore I
think.''
Without a brain - those few pounds of red meat atop our spinal
columns - thinking is impossible. The mind, and therefore the
self, is inextricably embedded in our physical bodies.
But a newborn brain is not yet a self, at least not much of one.
A self is also a lifetime of remembered experiences, somehow
woven into hundreds of billions of cranial neurons like a
picture into a cloth tapestry.
I visited my 88-year-old mother recently in Chattanooga. At one
point in our visit, she entertained me with a song she had
learned more than 80 years ago, ''My Grandfather's Clock.'' Some
readers will know it:
My Grandfather's clock was too tall for its shelf, so it stood
90 years on the floor...
As my mother called up the words of the song out of the distant
past, I marveled that they still existed inside her brain, along
with countless other shared memories that she recalls more
vividly than I do. What a thing is human memory! No library can
touch it for speed of recall. No computer memory can equal it
for volume.
It was bought on the morn of the day he was born and was always
his pleasure and pride ...The words came tumbling out. How? How
can that song possibly still be in there, intact, able to be
extracted and sung without erasing? I could tell that she was
proud to remember the song, as well she should be. The song is
part of who she is, a brick in the mansion of her self.
The 2000 Nobel Prize in medicine went to Eric Kandel, Paul
Greengard, and Arvid Carlsson for studies on the physiology of
memory. In his address to the Nobel Foundation, Kandel recounted
his own journey into the mansions of self.
He first became interested in the study of memory in 1950 as a
result of his readings in psychoanalysis as an undergraduate at
Harvard. Later, as a medical student, he began to find
psychoanalysis limiting; it treated the brain as a black box,
observable only from outside. Kandel wanted to open the box, to
see what was inside - to explore the mansion of memory as flesh
and blood.
He was convinced that memory was biological and that human
memory might have much in common with memory in other organisms.
His approach, therefore, would be reductionistic: Start with the
rudiments of memory in a simple organism, with the hope of
eventually understanding the apparent miracle of human memory.
Kandel took the sea slug Aplysia as his model. This fist-sized,
shell-less, aquatic snail has several advantages as an
experimental animal: It has only 20,000 central nerve cells,
rather than the tens of billions in mammalian brains, and the
cells are big, ten times bigger than human neurons. And Aplysia
can be trained to respond to stimuli. It learns and remembers.
When a sea slug remembers, changes happen at the places where
nerve cells touch each other, the synapses. Kandel, and others,
worked out the biochemistry of these changes, for both
short-term and long-term memory, and they showed that the
cellular and molecular changes at work in Aplysia's rudimentary
brain are present in mammals, too.
There may be as many as 100 billion nerve cells in the human
brain, and each one is connected to thousands of others.
Memories are stored as electrical and chemical changes at the
synapses where cell communicates with cell. A scribble. A
lifetime of experiences scribbled into flesh.
Ninety years without slumbering, tick tock tick tock. Its life
seconds numbering, tick tock tick tock ..."
The biochemical approach to understanding memory has been
wonderfully successful, but it is a long way from a sea slug to
an 88-year-old human who can remember the words of a song
learned more than eight decades ago. And not just a song.
People, faces, voices, places, literature, music, telephone
numbers, travels, likes, dislikes, loves, hurts, grandparents,
grandchildren, birthdays, funerals, current affairs, and the
grand pageant of human history - a vast and unique accumulation
of memories, profound and trivial, which are a human self.
As Kandel pointed out in his Nobel address, there is lots more
yet to learn, and full understanding will require the combined
efforts of molecular biologists, cognitive psychologists,
neurologists, psychiatrists, and perhaps even computer modelers.
The 21st century promises to be the century when we explore
every corner of the mansions of self, and understand, at least
in principle, how the brain gives rise to mind.
The sea slug Aplysia has confirmed that Descartes was wrong; The
human self is not a dualism of mind and matter, but rather an
efflorescence of self from matter - tick tock tick tock - a
shimmering exuberance of the stuff of the universe gathered in
the human brain into biochemical webs of astonishing complexity.
Chet Raymo is a professor of physics at Stonehill College and
the author of several books on science.
This story ran on page C2 of the Boston Globe on 11/27/2001.
© Copyright 2001 Globe Newspaper Company.
===============================This was distributed via the memetics list associated with the
Journal of Memetics - Evolutionary Models of Information Transmission
For information about the journal and the list (e.g. unsubscribing)
see: http://www.cpm.mmu.ac.uk/jom-emit
This archive was generated by hypermail 2b29 : Wed Nov 28 2001 - 18:55:59 GMT