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system involved in the hand writing process; in sec.
3 the problem of the stability in handwriting
emphasizing the most stable part of a writing and
showing the influence of a disease on these parts.
Finally in sec. 4 some results are reported by
processing handwritten sample produced by some
Alzheimer illness affected patients by stressing the
relationship between stability regions and disease
insurgence.
2 ANATOMICAL AND
NEURO-PHYSIOLOGICAL
ASPECTS OF HANDWRITING
The handwriting as neuromuscular activity is
described by starting from the neurophysiologic
point of view and arriving to the mechanics of the
neuromuscular system that allows the handwriting.
During the years of his live, a writer acquires at
subconscious level some graph logic features that
are synthesized in graphic strokes made increasingly
clear, safe, fast and unique, here called personal
strokes, that remain unchanged over time.
By looking at handwriting, it must be said that
humans have different types of movements:
"automatic" and "volunteers"; writing movements
are a combination of this two type. The ability to
move is made possible by the neurons in the cerebral
cortex of the motor area (Brodmann's area 4, also
called the primary motor area) at the origin of the
pyramidal system, that provide at the voluntary
movements of the muscles and the planning of the
motor gesture. The motor area controls all voluntary
movements, between these areas relative to the fine
movements of the hand between which the
movements necessary for writing; the voluntary
movement interacts with the involuntary movement
which belongs to the pre-motor area (area 6) which
starts the extra-pyramidal system. For writing-motor
processes are crucial sensory information, properly
those of the sphere proprioceptive (kinaesthetic and
sensitivity) that allow a continuous and accurate
movements (Guyton, A.C., Hall, J.E., 2006),
(Cattaneo, L., 1989).
This information, as well as through the
mediation of the cerebellum and of the specific
sensory areas, also converge directly on neurons of
the areas of motor skills (motor neurons and
neuromuscular junctions) and then operate without
the intervention of conscious perceptions. The
cerebellum has an important influence on all
movements of the arm, as a consequence, the
Figure 2: Example of the use of neurons to sense, motion
and connection.
(source: http://www.analisidellascrittura.com/Image/
neurofisiologia1(1).jpg)
behaviour of handwriting, allowing to perform all
movements with precision and harmony.
Alzheimer's disease is the most common form of
irreversible disabling degenerative dementia with
onset senile, and his one of first and is considered
one of the most serious diseases to social impact
(Borri, M., 2012), (Meek, P.D., McKeithan, E.K.,
Schumock, G.T., 1998), (Zhu, C.W., Sano, M.,
2006). In the brain of the patient is evident brain
atrophy, a sign of the death of neurons, which does
reduce the overall volume of the brain, which is
filled with cerebrospinal fluid and it does enlarge the
ventricles (Vallar, G., Papagno, C., 2007). The
diagnosis is usually confirmed by specific
behavioural assessments and cognitive tests, often
followed from imaging magnetic resonance, but the
computer-images based diagnostics allows only and
solely to ascertain the presence and effects of
cortical atrophy.
The first symptoms that appear are: impaired
memory and not aware of the disease. The course of
the disease and the symptom modes may be different
for each individual patient.
Clinical features: Alzheimer's gets worse, new
symptom joins to the existing, can be added aphasia,
agnosia and apraxia.
Having been in his youth a large volume of
activity mental/cognitive represents a protective
factor against Alzheimer's. The disease can be
recognized only with the neuropsychological
examination and not with the instrumental diagnosis,
and the main diagnosis of Alzheimer's occurs only
through clinical evaluation actually (Waldemar, G.,
Dubois, B., Emre, M., et al, 2007).
A complete description of the neuromuscular
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