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Neurobiology I – Bio 334
Suhita Nadkarni ([email protected])
Raghav Rajan ([email protected])
Monday – 10:30 – 11:25 am
Thursday – 2:30 – 3:25pm
01st August 2013 1 Bio 334 - Lecture 1 - History of
Neuroscience
What is neurobiology?
• Scientific study of the nervous system
(Wikipedia)
• Many different sub-areas and sub-
categories
01st August 2013 2 Bio 334 - Lecture 1 - History of
Neuroscience
Why study neurobiology?
Men ought to know that from the brain, and from the brain only, arise our pleasures, joy, laughter and jests, as well as our sorrows, pains, griefs and tears
- Hippocrates (400 BC)
If our brains were simple enough for us to understand them, we’d be so simple that we couldn’t
- Ian Stewart (mathematician)
01st August 2013 3
Bio 334 - Lecture 1 - History of Neuroscience
History of Neuroscience
• Gives an interesting perspective
01st August 2013 4 Bio 334 - Lecture 1 - History of
Neuroscience
Early neurosurgery - Trephination or
Trepannation – as early as 6500 BC
• Skulls discovered in France had holes in them (about 40/120)
• To treat injuries, migraines, epilepsy, etc.
https://en.wikipedia.org/wiki/Trepanning
01st August 2013 5 Bio 334 - Lecture 1 - History of
Neuroscience
Ancient Egyptians did not consider the
brain important
• Yet, early references to the brain by
them in 1700 B.C.
• Possibly by Imhotep (Mummy fame!),
great Egyptian surgeon
• References in the Edwin-Smith surgical
papyrus of patients
http://faculty.washington.edu/chudler/papy.html
01st August 2013 6 Bio 334 - Lecture 1 - History of
Neuroscience
Case 6: A gaping wound in the head, fracture of the skull
and opening of the meninges. This case describes the:
1.Convolutions of the brain - the author of the papyrus
describes these "like those corrugations which form molten
copper." This most likely refers to the wrinkled appearance
of the brain created by the gyri and sulci of the brain.
"Corrugations" of the Brain
2.Meninges (coverings of the brain) - described as the
membrane enveloping the brain.
"Membrane" enveloping the Brain
3.Cerebrospinal fluid - described as the fluid in the interior
of the head.
"Fluid" in the Interior of the Head
Case 6 was "An ailment not to be treated." http://faculty.washington.edu/chudler/papy.html
01st August 2013 7 Bio 334 - Lecture 1 - History of
Neuroscience
Ancient Greeks divided in their opinion
• Mind-body dualism
• The mind and body are separate
• What is mind? No matter. What is matter?
Never mind. – George Berkeley (Irish philosopher)
01st August 2013 8 Bio 334 - Lecture 1 - History of
Neuroscience
Brain or cephalocentric hypothesis
started around ~550 B.C.
• Pythagorus, Alcmaeon of Croton
• Studied vision
• Concluded that the eyes are light bearing
paths to the brain
• Eyes have light (phospenes) and water
(dissection)
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 9
http://schatz.sju.edu/neuro/nphistory/nphistory.html
Hippocrates – theory of humors
• Human beings have a soul and a body
• Body made up of 4 substances or humors
• Balance of the humors is important for good
health
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 10
http://www.hormones.gr/17/article/article.html
Hippocrates like Alcmaeon believed the
brain to be the seat of intelligence
• Seat of intelligence
• Controller of senses, emotion,
movement, etc…. (the works)
• Correctly diagnosed epilepsy, etc. as
disorders of the brain
• Also recognised that paralysis occurred on
the side opposite to the side with damage
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 11
http://www.princeton.edu/~cggross/Neuroscientist_95-1.pdf
Aristotle turns the clock back – “learning
by heart”
• Heart is the seat of intelligence
• Brain, lungs are all for cooling the
heart
• REASONS
– Heart develops first
– Is present in all organisms
– Is connected to all senses
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 12
http://www.princeton.edu/~cggross/Neuroscientist_95-1.pdf
Galen – puts us back on course
• Very interesting observations
• Sensory fibres – softer – for sensory experience
• Motor fibres - firmer – for action
• Similarly – cerebrum is soft and so is sensory
• Cerebellum – hard – must control motor function
• Cerebrum – soft, can be moulded – must therefore store memories
• Three lefts make a right and A few wrongs can also make a right!
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 13
http://en.wikipedia.org/wiki/Galen
http://www.cerebromente.org.br/n16/history/mind-history_i.html
Brain and nerves – part of a larger plumbing
system controlled by the pineal gland
• Animal spirit
(liquid + air)
• Brain a large clot
of phlegm
• Described
ventricles in great
detail
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 14
http://bertie.ccsu.edu/naturesci/Evolution/Unit10Background/GalenPhysio.html
Cell doctrine – ventricles and intelligence
• Nemesius and St. Augustine (130 – 200 A.D.)
• Anterior ventricle – “common sense”
• Middle ventricle – action
• Posterior ventricle - memory
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 15
http://schatz.sju.edu/neuro/nphistory/nphistory.html
http://www.cerebromente.org.br/n16/history/mind-history_i.html
Andreas Vesalius, using anatomy
discredited the ventricular theory
• Other
mammals like
the ass have
the same
organisation
• Ventricles
store animal
spirits
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 16
http://www.cerebromente.org.br/n16/history/mind-history_i.html
Descartes – Pineal gland controls all the
plumbing
• Small filaments that
can be controlled by
external stimuli
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 17
http://www.cerebromente.org.br/n16/history/mind-history_i.html
Pineal gland controls sleep and waking by
controlling the flow of animal spirits
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 18
http://www.cerebromente.org.br/n16/history/mind-history_i.html
A lot of careful anatomy, observations of
white matter, gray matter, etc.
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 19
Luigi Galvani - bioelectricity
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 20
http://electricityrit.blogspot.in/2783/02/frog-legs-galvanis-research-into.html http://en.wikipedia.org/wiki/Luigi_Galvani
Localization of function within the brain -
Phrenology
• Frafz Josef Gall
• Bumps on the head related to various functions
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 21
http://www.phrenology.com/franzjosephgall.html
http://www3.niu.edu/acad/psych/Millis/History/2004/phrenology.htm
Purkinje cells – described by Purkinje
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 22
https://en.wikipedia.org/wiki/Johannes_Purkinje
http://en.wikipedia.org/wiki/Purkinje_cell
Flourens – uniform function throughout
brain
• Through ablations suggested that the
whole brain was equivalent
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 23
http://www.columbia.edu/cu/psychology/courses/1010/mangels/neuro/history/history.html
Broca – localized function returns
Wernicke supports idea
• Broca’s aphasia – patient could only say
“Tan”
• Wernicke’s aphasia – patient spoke
nonsense
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 24
http://www.columbia.edu/cu/psychology/courses/1010/mangels/neuro/history/history.html
Localization set in stone – Broadmann
areas
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 25
http://www.appliedneuroscience.com/Brodmann_Areas.jpg https://en.wikipedia.org/wiki/Korbinian_Brodmann
Golgi and Cajal – the neuron doctrine –
Nobel prize in 1906
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 26
https://en.wikipedia.org/wiki/Camillo_Golgi
https://en.wikipedia.org/wiki/Santiago_Ram%C3%B3n_y_Cajal
Penfield – homunculus – Grandmother cell
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 27
http://www.columbia.edu/cu/psychology/courses/1010/mangels/neuro/history/history.html
https://en.wikipedia.org/wiki/Wilder_Penfield
http://teddysratlab.blogspot.in/2011/07/curious-things-we-learned-from-epilepsy.html
And now – Karl Deisseroth – optogenetics
Science fiction becomes reality
01st August 2013 Bio 334 - Lecture 1 - History of
Neuroscience 28