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Representations of the homunculus
The homunculus is also commonly used to describe the
distorted human figure drawn to reflect the relative sensory space
our body parts occupy on the cerebral cortex. The lips, hands, feet
and sex organs are considerably more sensitive than other parts
of the body, so the homunculus has grossly large lips, hands and
genitals. Well known in the field of neurology, this is also commonly
called 'the little man inside the brain.'Dr Wilder Penfield used
a similar image to depict the body according to the areas of the
motor cortex controlling it in voluntary movement. Sometimes thought
to be the brain's map of the body, the motor homunculus is really
a map of the proportionate association of the cortex with body members.
It also reflects kinesthetic proprioception, the body an with certain
types of brain damage. Like the sensory homunculus, the motor homunculus
looks distorted. For example the thumb which is used in thousands
of cotivities appears much larger than the thigh with its relatively
simple movement. The motor homunculus develops over time and differs
from one person to the next. The hand in the brain of an infant
is different to the hand in the brain of a concert pianist. This
kind of difference is open to introspection. You can probably flex
and extend the end of your thumb at will. Most people can do this
fairly easily, but relatively few can make analogous movements with
any of their other fingers. The difference is due to differences
in the functional organization of associated areas of the brain
A Homunculus argument accounts for a phenomenon in
terms of the very phenomenon that it is supposed to explain Homunculus
arguments are always fallacious. In the psychology and philosophy
of mind 'homunculus arguments' are extremely useful for detecting
where theories of mind fail or are incomplete.Homunculus arguments
are common in the theory of vision. Imagine a person watching a
movie. They see the images as something separate from them, projected
on the screen. How is this done? A simple theory might propose that
the light from the screen forms an image on the retinas in the eyes
and something in the at these as if they are the screen. The Homunculus
Argument shows this is not a full explanation because all that has
been done is to place an entire person, or homunculus, behind the
eye who gazes at the retinas. A more sophisticated argument might
propose that the images on the retinas are transferred to the visual
cortex where it is scanned. Again this cannot be a full explanation
because all that has been dto place a little person in the brain
behind the cortex. In the theory of vision the Homunculus Argument
invalidates theories that do not explain 'projection', the experience
that the viewing point is separate from the things that are seen.
Very few people would propose that there actually
is a little man in the brain looking at brain activity. However,
this proposal has been used as a 'straw man' in theories of mind.
Gilbert Ryle proposed that the human mind is known by its intelligent
acts. He argued that if there is an inner being inside the brain
that could steer its own thoughts then this would lead to an absurd
repetitive cycle or 'regress':
"According to the legend, whenever an agent does
anything intelligently, his act is preceded and steered by another
internal act of considering a regulative proposition appropriate
to his practical problem.""Must we then say that for the
..].. reflections how to act to be intelligent he must first reflect
how best to reflect how to act? The endlessness of this implied
regress shows that the application of the appropriateness does not
entail the occurrence of a process of considering this criterion."Ryle
is proposing that if inner reflection were a process then it would
be an endless activity if it occurred wholly within the brain .However,
if the argument is applied rigorously it should be phrased in such
a way is always that if a homunculus is required then the theory
is wrong. After all, homunculi do not exist.The homunculus argument
applied to Ryle's theory would be phrased in terms of whether the
mental attribute of 'reflecting upon things internally' can beby
the theory that the mind is 'intelligent acts' without the appearance
of a homunculus. The answer, provided by Ryle's own logic, is that
internal reflection would require a homunculus to prevent it from
becoming an infinite regress. Therefore with these assumptions the
Homunculus Argument does not support the theory that mind is wholly
due to intelligent acts.The example of Ryle's theory demonstrates
another Homunculus Argument in which it is possible to attribute
to the mind various properties such as 'internal reflection' that
are not universally accepted and use these contentiously to declare
that a theory of mind is invalid.
Representations of the homunculus
In the classic horror film Bride of Frankenstein, Dr. Frankenstein's
old teacher, Dr. Praetorius, shows him his own creations, a series
of miniature humanoids kept in specimen jars, including a bishop,
a king, a queen, a ballerina, a mermaid, and a devil. These are
clearly intended to be forms of homunculi. In his source study of
original novel upon which the film was based, Prof. Radu Florescu
notes that her father, William Godwin was quite familiar with the
lives and works of alchemists like Paracelsus and others, and their
theories on the creation of the homunculus. Florescu also notes
that Konrad Dippel, an alchemist whom he believes may have been
the inspiration for Dr. Frankenstein, was a student of Dr. David
Christianus.
German horror writer Hanns Heinz Ewers used the mandrake
method for creating a homunculus as the inspiration for his 1911
novel Alraune, in which a prostitute is impregnated with semen from
a hanged murderer to create a woman devoid of morals or conscience.
Several cinematic adaptations of Alraune have been made othe years,
the most recent in on Stroheim. The film Species also appears to
draw some inspiration from this variation on the homunculus legend.The
Japanese manga graphic novel Homunculus by Hideo Yamamoto refered
to sensory homunculus from neurology in meaning for explain about
their human experimental.In the American film The Golden Voyage
of Sinbad the homunculus is portrayed as a miniature winged gargoyle
looking creature, who is the nemesis of Sinbad.
In various works of fantasy and science fiction, the
term "homunculus" describes any man-made humans
or humanoid creatures that are created via alchemy or
magic. Such hounculi feature in the comedy film The
League of ins) and play a significant part in the story's
plot. Homunculi are the product of failed attempts to
resurrect humans who have died. Not possessinouls, they
kill without restraint. A homunculamed Roger figures
greatly into some of the Hellboy comic books. In the
Dungeons & Dragons role-playing game, wizard can
use a spell to make a homunculus. In the Magic: the
Gathering card game, tw creatures exist with "homunculus"
in their name. Both are blue creatures, blue being the
color of artificial creation and illusion, among other
things. In the Enix console role-playing game Valkyrie
Profile, the alchemist Lezard Valeth experiments with
homonculi. Among them are his minion Bellion, and numerous
female elven-like forms kept in large glass tubes.
Other uses of the name "homunculus"
Some of the smallest infusion pumps use osmotic power.
Basically, a bag of salt solution absorbs water through a membrane,
swelling its volume. The bag presses medicine out. The rate is precisely
controlled by the salt concentrations and pump volume. Osmotic pumps
are usually recharged with a syringe.Spring-powered clockwork infusion
pumps have been developed, and are sometimes still used in veterinary
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amounts quickly, with dramatically changing pressures and patient
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purpose, although they have not been deployed.Many infusion pumps
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blood from a patient, and air in the line, which can starve a patient's
tissues of oxygen if it floats to some part of a patient's body.
Safety features available on some pumps
The range of safety features varies widely with the
age and make of the pump. A state of the art pump in
2003 may have the following safety features:Certified
to have no single point . That is, no single cause of
failure should cause the pump to silently fail to operate
correctly. It should at least stop pumping and make
at least an audible error indication. This is a minimum
requirement on all human-rated infusion pumps of whatever
age. It is not required for veterinary infusion pumps.
Batteries, so the pump can operate if the power fails
or is unplugged.
Anti-free-flow devices prevent blood from draining from
the patient, or infusate from freely entering the patient,
when the infusion pump is being set-up.
A "down pressure" sensor will detect when
the patient's vein is blocked, or the line to the patient
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and epidural or low applications.
An "air-in-line" detector. A typical detector
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when air is being pumped. Some pumps actually measure
the volume, and may even have configurable volumes,
from 0.1 to 2 ml of air. None of these amounts can cause
harm, but sometimes the air can interfere with the infusion
of a low-dose medicine.
An "up pressure" sensor can detect when the
bag or syringe is empty, or even if the bag or syringe
is being squeezed.
Many pumps include an internal elog of the last several thousand
therapy events. These
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