By Andrea Gawrylewski

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Facelessness Faced

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After giving a lecture in Windsor, England last February,
neuroscientist Bradley
Duchaine was approached by a man who'd been in the audience. He told
Duchaine,
professor at the Institute of Cognitive Neuroscience, University
College London,
that he sometimes had trouble recognizing faces, even those of people
he knew.
Duchaine brought him to his lab, ran some tests, and diagnosed him
with
prosopagnosia, characterized as an inability to recognize familiar
faces. "He
was certainly atrocious" at recognizing faces, says Duchaine. When
given
face-memory tests and shown a battery of celebrity photos, "most
people get
about 80% correct. This [person] scored about 40%." He was British,
but "he
wasn't recognizing Tony Blair."
While developmental prosopagnosia is estimated to affect some two
percent of the
world's population, research on the subject is still being
accumulated, mostly
because human subjects are few and far between. Most of the people
Duchaine has
tested had found him on the Internet while searching for information
about their
problem with faces, or they read about him in the news. People with
the
impairment usually try to hide it, compensating by noticing other
clues about a
person's identity, such as voice or clothing. Duchaine and his
colleagues have
tested about 120 people for the symptoms of the disorder, and they
performed
fMRI brain scans on approximately 10 patients.

People with prosopagnosia usually try to hide it, compensating by
noticing
other clues about a person's identity.


The concept that certain regions of the brain specialize in face
processing was
suggested in the late 1960s by Jerry Lettvin, who coined the term
"grandmother
cell" while a professor at the Massachusetts Institute of Technology.
Early
experiments in monkeys showed that specific neurons responded only to
hands and
faces. Over time, researchers narrowed the regions involved to three
areas in
the temporal and occipital lobes: specifically, the fusiform face
area,
occipital face area, and superior temporal sulcus.




The idea that specific brain regions handle facial recognition
remained
controversial until a year ago, when Doris Tsao from Harvard
University and
colleagues found neuronal activity that was exclusively triggered by
face
perception. By inserting miniscule electrodes into these specific
regions of the
macaque brain, Tsao saw a specific millivoltage produced by neurons in
the face
regions of the brain that did not occur when the monkeys looked at
other objects
(Science, 311:670-4, 2006).

Duchaine's fMRI scans show, too, that the three brain regions light up
when the
patient is looking at pictures of faces. When prosopagnosics see a
familiar
face, they show the same brain activity in these key areas as when
they saw the
face for the first time. Nonprosopagnosics, however, show less
regional activity
when looking at a familiar face, suggesting their brains don't need to
work as
hard.

So if face recognition is localized to three brain regions, what
neurologic
changes are behind prosopagnosia? There are some early clues. Cibu
Thomas, in
collaboration with Marlene Behrmann at Carnegie Mellon University,
recently
correlated prosopagnosic symptoms with a disruption of the connections
between
the brain regions involved in face processing. This work, still
unpublished,
indicates that face-blindness stems from problems in these neuronal
networks,
and not an impairment within one region or another in the brain. This
would also
explain why some people with prosopagnosia can have a structurally
intact
fusiform face area (previously thought to be the only area for face
processing)
and yet still present with symptoms.

"It turns out there's not just one region but a system of regions
[processing
faces in some way] - six different patches in the monkey brain," says
Tsao.
"We're trying to understand what each of them is doing at the level of
single
cells; one is highly specialized for processing which way someone is
looking;
another [is] strongly implicated in object recognition." There are
many
important reasons for face specialization. "We spend an awful lot of
time
extracting information from faces," says Duchaine. There's "an awful
lot of
information about who somebody is, what they're looking at, how
attractive they
are, and there's a measure of debate over how these face processes
disassociate"
in the brain.

Source: TheScientist
http://www.the-scientist.com/article/home/53774/

Lance wrote:
> By Andrea Gawrylewski
> 
> --------------------------------------------------------------------------------
> 
> Facelessness Faced
> 
> --------------------------------------------------------------------------------
> 
> After giving a lecture in Windsor, England last February,
> neuroscientist Bradley
> Duchaine was approached by a man who'd been in the audience. He told
> Duchaine,
> professor at the Institute of Cognitive Neuroscience, University
> College London,
> that he sometimes had trouble recognizing faces, even those of people
> he knew.
> Duchaine brought him to his lab, ran some tests, and diagnosed him
> with
> prosopagnosia, characterized as an inability to recognize familiar
> faces. "He
> was certainly atrocious" at recognizing faces, says Duchaine. When
> given
> face-memory tests and shown a battery of celebrity photos, "most
> people get
> about 80% correct. This [person] scored about 40%." He was British,
> but "he
> wasn't recognizing Tony Blair."
 >
Is there anything you can take to arrive at this happy state?

Peter H.M.Brooks wrote:
> Lance wrote:
> > By Andrea Gawrylewski
> >
> > --------------------------------------------------------------------------------
> >
> > Facelessness Faced
> >
> > --------------------------------------------------------------------------------
> >
> > After giving a lecture in Windsor, England last February,
> > neuroscientist Bradley
> > Duchaine was approached by a man who'd been in the audience. He told
> > Duchaine,
> > professor at the Institute of Cognitive Neuroscience, University
> > College London,
> > that he sometimes had trouble recognizing faces, even those of people
> > he knew.
> > Duchaine brought him to his lab, ran some tests, and diagnosed him
> > with
> > prosopagnosia, characterized as an inability to recognize familiar
> > faces. "He
> > was certainly atrocious" at recognizing faces, says Duchaine. When
> > given
> > face-memory tests and shown a battery of celebrity photos, "most
> > people get
> > about 80% correct. This [person] scored about 40%." He was British,
> > but "he
> > wasn't recognizing Tony Blair."
>  >
> Is there anything you can take to arrive at this happy state?

You don't like Blair much. OK. But surely an inability to recognize
someone you dislike or someone who is a  possible enemy is not a good
condition to be in?

Lance

Lance wrote:
> 
> Peter H.M.Brooks wrote:
>> Lance wrote:
>>> By Andrea Gawrylewski
>>>
>>> --------------------------------------------------------------------------------
>>>
>>> Facelessness Faced
>>>
>>> --------------------------------------------------------------------------------
>>>
>>> After giving a lecture in Windsor, England last February,
>>> neuroscientist Bradley
>>> Duchaine was approached by a man who'd been in the audience. He told
>>> Duchaine,
>>> professor at the Institute of Cognitive Neuroscience, University
>>> College London,
>>> that he sometimes had trouble recognizing faces, even those of people
>>> he knew.
>>> Duchaine brought him to his lab, ran some tests, and diagnosed him
>>> with
>>> prosopagnosia, characterized as an inability to recognize familiar
>>> faces. "He
>>> was certainly atrocious" at recognizing faces, says Duchaine. When
>>> given
>>> face-memory tests and shown a battery of celebrity photos, "most
>>> people get
>>> about 80% correct. This [person] scored about 40%." He was British,
>>> but "he
>>> wasn't recognizing Tony Blair."
>>  >
>> Is there anything you can take to arrive at this happy state?
> 
> You don't like Blair much. OK. But surely an inability to recognize
> someone you dislike or someone who is a  possible enemy is not a good
> condition to be in?
> 
Yes, of course it isn't. I hardly ever see photographs of the creature, 
so it isn't a big problem for me, it was more of a joke.

I was interested to see that his shamelessness appears utterly 
boundless. He's in the process of signing up to be a Catholic, 
converting to it, after being on record as a support of many measures 
that are directly against Catholic doctrine. He's happy to do this 
without recanting any of his previous positions, despite being prepared 
to take a public oath to the effect that he believes that all the 
teachings of the Catholic church are true.

I just wonder quite what advancement he hopes for from joining up, and I 
just wish, as you know, that people wouldn't elect psychopaths.