[Music]
imagine you’re born blind
you adapt to this condition and you
become very good at navigating with
outside at remembering where are places
object at localizing sounds even at
reading with your fingers in some sense
you become with like this Marvel
superhero daredevil you compensate for
the lack of vision by developing some
kind of supernatural skills in your
remaining senses then someone comes to
you and tell you I can fix your eyes and
he can provide you the gift of sight
a miraculous will that be but is it if
we looked at the very few cases in the
literature of people who recovered sight
after a lifelong experience of blindness
we see that what was expected to be
miraculous can sometimes turns out to be
a disaster take for example patient s B
he was investigated by the famous
psychologist Richard Gregory as we
regain sight at age 52 and in his
monograph about the case which art
Gregory explained that his case is in
some way tragic he lifts with one of the
greatest handicap but yes it lifts with
enthusiasm and energy and when his
handicap was apparently swept away as by
miracle he lost is peace and
self-respect actually a few years of the
recovering sight s be committed suicide
in my research I’m trying to understand
what may happen in the brain of blind
individuals that could explain this
somehow tragic case stories I’m a
cognitive neuroscientist so during my
work I’m often contemplating this
fascinating but very complex project of
evolution that is the human brain we try
to understand oh this brain implements
the mind or cognition and per net
perception emerge from brain activity so
for example what we know is that when
you see something
it activates the back part of your brain
what we call the occipital cortex and it
does so in an organized fashion you will
have some region but some what we call
some computational unit that will prefer
to respond to some specific input for
example you will have some region that
we prefer to respond to faces more than
to any other object or the region that
will refer to respond to places or
scenes or the region that will prefer to
response to inanimate object at least if
you don’t drink too much of it and
finally other region that will prefer to
response to object in motion more than
to any static object and all these
computational units will interact with
each other
to create a unified and current
perception of your environment or is
this organization emerging what we know
is that there is a genetic master plan
that is at least partly driving this
organization although we know that first
because this organization is some
somehow universal is highly similar
between each of us second you can find
trace of this organization in very young
babies and finally you can find this
organization even in our evolutionary
ancestors like primates all this
together suggests that there is a
genetic determination in the way this
organization emerge does that mean that
experience plays no role for instance
what would happen if someone is born
blind will this region remain silent and
not participate in anything if you
actually test that in the laboratory
this is not what you observe we observe
a phenomenon that we call cross model
plasticity the fact that the region
typically dedicated to process visual
information massively reorganized to
process auditory or tactile input and
what is quite fascinating with this
reorganization is someone that it
follows a division of computational
labour that is similar between blind and
sighted subjects you remember this
region that I said was specific for
visual motion in the sighted actually
this region remains selective for motion
in blind people but process motion in
the auditory or tactile modality so it
seems that this region maintain is
function but apply this function to a
non visual modality so this kind of
discoveries are very important for us to
understand on nature and nurture
interact to shape brain development on
one side we clearly see that experience
plays a dramatic role in case of visual
deprivation those region massively
reorganize and play participate in
another type of processing the
processing of another sensory modality
but at the same time we see that there
are intrinsic forces that constrain the
way this reorganization expresses so
I’ve just said that in early blind
people the occipital cortex normally
visual functionally participate in non
visual processing what would happen if a
blind subject recover site or this newly
required visual input will interact or
even interfere with this auditory or
tactile input that are no rooted in the
occipital cortex of this blind subject
actually a few years ago we had the
unique opportunity to explore this
question by investigating the case of a
patient which was born with massive
visual impairment up to the moment she
recovered side at age 47 and what we did
is that we tested this person at least
all the brain of this person react
before and after site recovery and what
we saw before site recovery is that
because she was highly visually impaired
her brain reaction the reaction of our
occipital cortex to visual input was
highly clumsy but because she lived as a
blind subject she had massive activity
in this region for auditory information
for example after the reacquisition of
sight what we saw is that this region
progressively became tuned to the visual
input but what was probably the most
striking discovery is that even seven
months
after site recovery we could still find
trace of auditory activity in this
region so it means that if you are born
blind and live a life as a blind subject
and get vision restored as an adult you
have an occipital cortex that
simultaneously react to vision and to
audition and we believe that this
interaction in the occipital cortex may
potentially create some interference can
challenge the optimal reacquisition
of sight actually you do not need a full
experience a full life of blindness to
experience that those kind of
reorganization even if the blindness is
very short but early in life in the most
sensitive period of blind development
like in the case of these babies born
with dense bilateral cataract that got
operated very early in life few weeks of
humans after birth if you test them when
they are adults actually even in these
people you can find trace of auditory
activity in the occipital cortex and
again this may potentially explain why
these people never react wire perfect
vision even in adulthood so what I
wanted to tell you today is that you can
look at brain plasticity in two ways
there is obviously the adaptive side of
plasticity the fact that the brain can
reorganize to interact with is in the
environment to potential eyes is
capacity but there is also a maladaptive
way of looking at the palate plasticity
the fact that reorganization that are
put in place early in life are very
difficult to undo and potentially could
interfere with the reacquisition of
sensory information later in life so I
hope I’ve convinced you today that the
study of brain plasticity is an
important topic it’s also a very timely
topic why because we are living
exponential increase in the medicine of
sensory restoration so it’s very
important to tackle this question now
what we hope is that we can use
neuroscience to predict who will be the
good or the bad candidate for sensory
restoration and potentially also that we
can leverage all knowledge
about brain plasticity to design better
tailored rehabilitation procedure thank
you
[Applause]
imagine you’re born blind
you adapt to this condition and you
become very good at navigating with
outside at remembering where are places
object at localizing sounds even at
reading with your fingers in some sense
you become with like this Marvel
superhero daredevil you compensate for
the lack of vision by developing some
kind of supernatural skills in your
remaining senses then someone comes to
you and tell you I can fix your eyes and
he can provide you the gift of sight
a miraculous will that be but is it if
we looked at the very few cases in the
literature of people who recovered sight
after a lifelong experience of blindness
we see that what was expected to be
miraculous can sometimes turns out to be
a disaster take for example patient s B
he was investigated by the famous
psychologist Richard Gregory as we
regain sight at age 52 and in his
monograph about the case which art
Gregory explained that his case is in
some way tragic he lifts with one of the
greatest handicap but yes it lifts with
enthusiasm and energy and when his
handicap was apparently swept away as by
miracle he lost is peace and
self-respect actually a few years of the
recovering sight s be committed suicide
in my research I’m trying to understand
what may happen in the brain of blind
individuals that could explain this
somehow tragic case stories I’m a
cognitive neuroscientist so during my
work I’m often contemplating this
fascinating but very complex project of
evolution that is the human brain we try
to understand oh this brain implements
the mind or cognition and per net
perception emerge from brain activity so
for example what we know is that when
you see something
it activates the back part of your brain
what we call the occipital cortex and it
does so in an organized fashion you will
have some region but some what we call
some computational unit that will prefer
to respond to some specific input for
example you will have some region that
we prefer to respond to faces more than
to any other object or the region that
will refer to respond to places or
scenes or the region that will prefer to
response to inanimate object at least if
you don’t drink too much of it and
finally other region that will prefer to
response to object in motion more than
to any static object and all these
computational units will interact with
each other
to create a unified and current
perception of your environment or is
this organization emerging what we know
is that there is a genetic master plan
that is at least partly driving this
organization although we know that first
because this organization is some
somehow universal is highly similar
between each of us second you can find
trace of this organization in very young
babies and finally you can find this
organization even in our evolutionary
ancestors like primates all this
together suggests that there is a
genetic determination in the way this
organization emerge does that mean that
experience plays no role for instance
what would happen if someone is born
blind will this region remain silent and
not participate in anything if you
actually test that in the laboratory
this is not what you observe we observe
a phenomenon that we call cross model
plasticity the fact that the region
typically dedicated to process visual
information massively reorganized to
process auditory or tactile input and
what is quite fascinating with this
reorganization is someone that it
follows a division of computational
labour that is similar between blind and
sighted subjects you remember this
region that I said was specific for
visual motion in the sighted actually
this region remains selective for motion
in blind people but process motion in
the auditory or tactile modality so it
seems that this region maintain is
function but apply this function to a
non visual modality so this kind of
discoveries are very important for us to
understand on nature and nurture
interact to shape brain development on
one side we clearly see that experience
plays a dramatic role in case of visual
deprivation those region massively
reorganize and play participate in
another type of processing the
processing of another sensory modality
but at the same time we see that there
are intrinsic forces that constrain the
way this reorganization expresses so
I’ve just said that in early blind
people the occipital cortex normally
visual functionally participate in non
visual processing what would happen if a
blind subject recover site or this newly
required visual input will interact or
even interfere with this auditory or
tactile input that are no rooted in the
occipital cortex of this blind subject
actually a few years ago we had the
unique opportunity to explore this
question by investigating the case of a
patient which was born with massive
visual impairment up to the moment she
recovered side at age 47 and what we did
is that we tested this person at least
all the brain of this person react
before and after site recovery and what
we saw before site recovery is that
because she was highly visually impaired
her brain reaction the reaction of our
occipital cortex to visual input was
highly clumsy but because she lived as a
blind subject she had massive activity
in this region for auditory information
for example after the reacquisition of
sight what we saw is that this region
progressively became tuned to the visual
input but what was probably the most
striking discovery is that even seven
months
after site recovery we could still find
trace of auditory activity in this
region so it means that if you are born
blind and live a life as a blind subject
and get vision restored as an adult you
have an occipital cortex that
simultaneously react to vision and to
audition and we believe that this
interaction in the occipital cortex may
potentially create some interference can
challenge the optimal reacquisition
of sight actually you do not need a full
experience a full life of blindness to
experience that those kind of
reorganization even if the blindness is
very short but early in life in the most
sensitive period of blind development
like in the case of these babies born
with dense bilateral cataract that got
operated very early in life few weeks of
humans after birth if you test them when
they are adults actually even in these
people you can find trace of auditory
activity in the occipital cortex and
again this may potentially explain why
these people never react wire perfect
vision even in adulthood so what I
wanted to tell you today is that you can
look at brain plasticity in two ways
there is obviously the adaptive side of
plasticity the fact that the brain can
reorganize to interact with is in the
environment to potential eyes is
capacity but there is also a maladaptive
way of looking at the palate plasticity
the fact that reorganization that are
put in place early in life are very
difficult to undo and potentially could
interfere with the reacquisition of
sensory information later in life so I
hope I’ve convinced you today that the
study of brain plasticity is an
important topic it’s also a very timely
topic why because we are living
exponential increase in the medicine of
sensory restoration so it’s very
important to tackle this question now
what we hope is that we can use
neuroscience to predict who will be the
good or the bad candidate for sensory
restoration and potentially also that we
can leverage all knowledge
about brain plasticity to design better
tailored rehabilitation procedure thank
you
[Applause]
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