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Envejecimiento
cerebral
normal
y
patológico
…

terrenos
donde
la
investigación
podría
hacer
avanzar
nuestros
conocimientos
en

el
envejecimiento
cerebral,
especialmente
en
el
estudio
pormenorizado
de
los

individuos
controles
sanos
de
entre
30
y
60
años,
en
el
de
los
“centenarios”
con
y

sin
demencia
y
en
grupos
con
características
diferenciales
neuropsicológicas

(posibles
estadíos
intermedios
de
EA
según
el
nuevo
“lexicón”).
También
sería
de

gran
interés
estudiar
comparativamente
el
envejecimiento
cerebral
humano
con

el
de
otras
especies
de
mamíferos
que
no
presentaran
patología
amiloide
o
tau
y

con
los
primates
que
pueden
presentar
patología
amiloidea.
En
este
último

sentido,
los
animales
transgénicos
con
patología
inducida
amiloide
o/y
tau

también
serían
importantes
fuentes
de
información.

Palabras
clave:
Senilidad
cerebral
normal;
senilidad
cerebral
patológica;

continuum;
Enfermedad
de
Alzheimer.

ABSTRACT

Normal
and
pathological
brain
aging:
a
physiopathological
continuum
or
an

involutive
duality

For
years,
there
is
a
controversy
whether
there
is
a
two-­-way
(involutive
duality)

of
senile
involution
of
the
brain,
which
may
be
called,
respectively,
pathway
to
the

physiological
or
"
normal"
senility,
without
signs
of
dementia
but
with
neuronal

adaptative
responses,
and
pathway
to
"pathological
"
senility
or
Alzheimer's

Disease
(AD),
which
is
characterized
by
the
appearance
of
a
progressive
dementia,

or,
conversely,
a
single
way
(continuum)
leading
from
the
first
morphological
or

functional
signs
of
senile
involution
until
the
final
stage
of
AD
dementia
in
all

individuals.
Moreover,
in
recent
years,
a
thorough
review
of
the
concepts
of
the

pathological
senility
/
EA
is
producing,
so
that
is
not
now
considered
necessary
to

have
dementia
to
diagnose
a
pathological
aging
process
because
it
is
considered

that
the
pathological
aging
/
EA
is
started
at
the
time
that
a
disturbance
in

cognitive
brain
circuits
and
/
or
neuropathological
changes
occurs.
With
these

new
criteria
different
clinic-­-pathological
stages
are
supposed
from
normal
senility

to
terminal
pathological
senility
/
EA,
without
dementia
(prodromal
or

asymptomatic)
and
with
varying
degrees
of
dementia.
In
this
review
the
reasons

given
in
defense
of
one
or
another
theory
are
analyzed,
as
well
as
the

morphofunctional
features
of
normal
and
pathological
senile
brains.
Most
studies

indicate
that
there
are
very
marked
differential
characteristics
between
normal

brains
without
dementia
and
senile
pathological
brains
with
dementia,
but
in

other,
large
discrepancies
exist
between
the
presence
or
absence
of
dementia
and

the
existence
or
not
of
neuropathological
signs.
The
existence
or
not
of
the

continuum
also
has
a
very
important
practical
implication
for
both
prevention
and

care
of
the
elderly,
because
the
possible
number
of
individuals
affected:
the
entire

501