<s>
The	O
visual	B-Algorithm
N1	I-Algorithm
is	O
a	O
visual	O
evoked	B-Algorithm
potential	I-Algorithm
,	O
a	O
type	O
of	O
event-related	O
electrical	O
potential	O
(	O
ERP	B-Algorithm
)	O
,	O
that	O
is	O
produced	O
in	O
the	O
brain	O
and	O
recorded	O
on	O
the	O
scalp	O
.	O
</s>
<s>
The	O
N1	B-Algorithm
is	O
so	O
named	O
to	O
reflect	O
the	O
polarity	O
and	O
typical	O
timing	O
of	O
the	O
component	O
.	O
</s>
<s>
The	O
N1	B-Algorithm
deflection	O
may	O
be	O
detected	O
at	O
most	O
recording	O
sites	O
,	O
including	O
the	O
occipital	O
,	O
parietal	O
,	O
central	O
,	O
and	O
frontal	O
electrode	O
sites	O
.	O
</s>
<s>
Although	O
,	O
the	O
visual	B-Algorithm
N1	I-Algorithm
is	O
widely	O
distributed	O
over	O
the	O
entire	O
scalp	O
,	O
it	O
peaks	O
earlier	O
over	O
frontal	O
than	O
posterior	O
regions	O
of	O
the	O
scalp	O
,	O
suggestive	O
of	O
distinct	O
neural	O
and/or	O
cognitive	O
correlates	O
.	O
</s>
<s>
The	O
N1	B-Algorithm
is	O
elicited	O
by	O
visual	O
stimuli	O
,	O
and	O
is	O
part	O
of	O
the	O
visual	O
evoked	B-Algorithm
potential	I-Algorithm
–	O
a	O
series	O
of	O
voltage	O
deflections	O
observed	O
in	O
response	O
to	O
visual	O
onsets	O
,	O
offsets	O
,	O
and	O
changes	O
.	O
</s>
<s>
Both	O
the	O
right	O
and	O
left	O
hemispheres	O
generate	O
an	O
N1	B-Algorithm
,	O
but	O
the	O
laterality	O
of	O
the	O
N1	B-Algorithm
depends	O
on	O
whether	O
a	O
stimulus	O
is	O
presented	O
centrally	O
,	O
laterally	O
,	O
or	O
bilaterally	O
.	O
</s>
<s>
When	O
a	O
stimulus	O
is	O
presented	O
centrally	O
,	O
the	O
N1	B-Algorithm
is	O
bilateral	O
.	O
</s>
<s>
When	O
presented	O
laterally	O
,	O
the	O
N1	B-Algorithm
is	O
larger	O
,	O
earlier	O
,	O
and	O
contralateral	O
to	O
the	O
visual	O
field	O
of	O
the	O
stimulus	O
.	O
</s>
<s>
When	O
two	O
visual	O
stimuli	O
are	O
presented	O
,	O
one	O
in	O
each	O
visual	O
field	O
,	O
the	O
N1	B-Algorithm
is	O
bilateral	O
.	O
</s>
<s>
In	O
the	O
latter	O
case	O
,	O
the	O
N1	B-Algorithm
's	O
asymmetrical	O
skewedness	O
is	O
modulated	O
by	O
attention	O
.	O
</s>
<s>
Additionally	O
,	O
its	O
amplitude	B-Application
is	O
influenced	O
by	O
selective	O
attention	O
,	O
and	O
thus	O
it	O
has	O
been	O
used	O
to	O
study	O
a	O
variety	O
of	O
attentional	O
processes	O
.	O
</s>
<s>
Although	O
the	O
N1	B-Algorithm
is	O
an	O
early	O
visual	O
component	O
that	O
is	O
part	O
of	O
the	O
normal	O
response	O
to	O
visual	O
stimulation	O
,	O
it	O
has	O
been	O
studied	O
most	O
extensively	O
with	O
respect	O
to	O
its	O
sensitivity	O
to	O
selective	O
attention	O
.	O
</s>
<s>
Initial	O
studies	O
focusing	O
on	O
the	O
modulation	O
of	O
the	O
N1	B-Algorithm
amplitude	B-Application
with	O
respect	O
to	O
attention	O
found	O
limited	O
evidence	O
for	O
N1	B-Algorithm
attention	O
effects	O
.	O
</s>
<s>
However	O
,	O
uncertainty	O
about	O
the	O
relationship	O
between	O
N1	B-Algorithm
amplitude	B-Application
and	O
attention	O
was	O
resolved	O
by	O
Haider	O
,	O
Spong	O
,	O
and	O
Lindsley	O
's	O
(	O
1964	O
)	O
groundbreaking	O
study	O
in	O
which	O
levels	O
of	O
attention	O
were	O
found	O
to	O
systematically	O
relate	O
to	O
variation	O
in	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
.	O
</s>
<s>
Importantly	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
systematically	O
varied	O
with	O
the	O
response	O
to	O
the	O
dim	O
flashes	O
.	O
</s>
<s>
As	O
accuracy	O
and	O
attention	O
decreased	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
decreased	O
,	O
suggesting	O
that	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
is	O
intimately	O
tied	O
to	O
levels	O
of	O
attention	O
.	O
</s>
<s>
Subsequent	O
studies	O
employing	O
different	O
attention	O
manipulations	O
found	O
similar	O
results	O
,	O
providing	O
further	O
support	O
for	O
the	O
link	O
between	O
the	O
N1	B-Algorithm
and	O
attention	O
.	O
</s>
<s>
In	O
one	O
study	O
,	O
subjects	O
directed	O
attention	O
to	O
different	O
types	O
of	O
visual	O
stimuli	O
,	O
and	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
to	O
the	O
visual	O
stimuli	O
varied	O
according	O
to	O
whether	O
they	O
were	O
attended	O
.	O
</s>
<s>
More	O
specifically	O
,	O
the	O
N1	B-Algorithm
was	O
greater	O
for	O
stimuli	O
that	O
were	O
attended	O
to	O
versus	O
those	O
that	O
were	O
ignored	O
.	O
</s>
<s>
A	O
later	O
study	O
by	O
Van	O
Voorhis	O
&	O
Hillyard	O
(	O
1977	O
)	O
examined	O
amplitude	B-Application
changes	O
in	O
the	O
N1	B-Algorithm
during	O
a	O
task	O
in	O
which	O
light	O
flashes	O
were	O
concurrently	O
delivered	O
to	O
the	O
left	O
or	O
right	O
visual	O
field	O
in	O
independently	O
random	O
sequences	O
.	O
</s>
<s>
Enhancement	O
of	O
the	O
N1	B-Algorithm
at	O
the	O
occipital	O
site	O
was	O
found	O
when	O
attention	O
was	O
directed	O
to	O
the	O
field	O
in	O
which	O
light	O
flashes	O
were	O
delivered	O
.	O
</s>
<s>
In	O
comparison	O
,	O
the	O
N1	B-Algorithm
were	O
smaller	O
for	O
flashes	O
that	O
occurred	O
in	O
the	O
field	O
opposite	O
of	O
attentional	O
focus	O
.	O
</s>
<s>
When	O
attention	O
was	O
divided	O
between	O
the	O
left	O
and	O
right	O
fields	O
,	O
the	O
N1	B-Algorithm
amplitude	B-Application
was	O
intermediate	O
.	O
</s>
<s>
The	O
attention-related	O
modulation	O
of	O
the	O
N1	B-Algorithm
produced	O
evidence	O
of	O
selective	O
visual	O
attention	O
similar	O
to	O
the	O
attention	O
effect	O
discovered	O
in	O
the	O
auditory	O
modality	O
,	O
in	O
which	O
the	O
auditory	O
N100	B-Algorithm
varies	O
according	O
to	O
selective	O
attention	O
within	O
the	O
auditory	O
field	O
.	O
</s>
<s>
After	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
was	O
found	O
to	O
vary	O
according	O
to	O
levels	O
of	O
attention	O
,	O
researchers	O
became	O
interested	O
in	O
how	O
identical	O
stimuli	O
were	O
perceived	O
when	O
they	O
were	O
attended	O
versus	O
unattended	O
.	O
</s>
<s>
When	O
targets	O
in	O
the	O
attended	O
visual	O
field	O
are	O
compared	O
to	O
targets	O
in	O
the	O
unattended	O
visual	O
field	O
,	O
the	O
unattended	O
targets	O
are	O
found	O
to	O
elicit	O
a	O
smaller	O
N1	B-Algorithm
than	O
the	O
attended	O
targets	O
,	O
suggesting	O
that	O
attention	O
acts	O
as	O
a	O
sensory	O
gain	O
mechanism	O
that	O
enhances	O
perception	O
of	O
attended	O
(	O
vs	O
.	O
unattended	O
)	O
stimuli	O
.	O
</s>
<s>
Thus	O
,	O
this	O
paradigm	O
provides	O
insight	O
into	O
how	O
putting	O
attention	O
in	O
the	O
correct	O
versus	O
incorrect	O
location	O
influences	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
.	O
</s>
<s>
The	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
varies	O
with	O
respect	O
to	O
accurately	O
cued	O
,	O
inaccurately	O
cued	O
,	O
and	O
neutrally	O
cued	O
trials	O
.	O
</s>
<s>
In	O
trials	O
in	O
which	O
attention	O
was	O
directed	O
toward	O
the	O
square	O
in	O
which	O
the	O
target	O
was	O
presented	O
(	O
accurately	O
cued	O
trials	O
)	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
is	O
larger	O
than	O
in	O
both	O
a	O
)	O
trials	O
in	O
which	O
attention	O
was	O
directed	O
to	O
all	O
squares	O
(	O
neutrally	O
cued	O
trials	O
)	O
and	O
b	O
)	O
trials	O
in	O
which	O
attention	O
was	O
directed	O
to	O
the	O
wrong	O
square	O
(	O
inaccurately	O
cued	O
trials	O
)	O
,	O
suggesting	O
that	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
represents	O
a	O
benefit	O
for	O
placing	O
attention	O
in	O
the	O
correct	O
location	O
.	O
</s>
<s>
The	O
amplitude	B-Application
,	O
or	O
the	O
size	O
,	O
of	O
the	O
N1	B-Algorithm
is	O
measured	O
by	O
taking	O
the	O
average	O
voltage	O
within	O
the	O
window	O
that	O
typically	O
encompasses	O
the	O
N1	B-Algorithm
(	O
about	O
150	O
to	O
200	O
ms	O
post-stimulus	O
)	O
.	O
</s>
<s>
Because	O
the	O
N1	B-Algorithm
is	O
a	O
negative-going	O
component	O
,	O
"	O
larger	O
"	O
amplitudes	B-Application
correspond	O
to	O
being	O
more	O
negative	O
,	O
whereas	O
"	O
smaller	O
"	O
amplitudes	B-Application
correspond	O
to	O
being	O
less	O
negative	O
.	O
</s>
<s>
Research	O
has	O
suggested	O
that	O
the	O
amplitude	B-Application
of	O
N1	B-Algorithm
is	O
affected	O
by	O
certain	O
visual	O
parameters	O
,	O
including	O
stimulus	O
angularity	O
and	O
luminance	O
,	O
both	O
of	O
which	O
are	O
directly	O
related	O
to	O
the	O
size	O
of	O
N1	B-Algorithm
.	O
</s>
<s>
The	O
amplitude	B-Application
of	O
N1	B-Algorithm
is	O
also	O
greater	O
in	O
response	O
to	O
stimuli	O
in	O
attended	O
vs.	O
unattended	O
locations	O
.	O
</s>
<s>
Conversely	O
,	O
amplitude	B-Application
is	O
decreased	O
when	O
the	O
interstimulus	O
interval	O
(	O
i.e.	O
,	O
the	O
amount	O
of	O
time	O
between	O
successive	O
presentations	O
of	O
stimuli	O
)	O
is	O
increased	O
for	O
stimuli	O
at	O
attended	O
locations	O
.	O
</s>
<s>
Amplitude	B-Application
effects	O
on	O
the	O
N1	B-Algorithm
are	O
absent	O
during	O
simple	O
Reaction	O
Time	O
tasks	O
,	O
which	O
only	O
require	O
subjects	O
to	O
make	O
a	O
rapid	O
response	O
to	O
stimuli	O
.	O
</s>
<s>
This	O
finding	O
suggests	O
that	O
N1	B-Algorithm
is	O
linked	O
to	O
visual	O
discrimination	O
processes	O
.	O
</s>
<s>
Researchers	O
interested	O
in	O
understanding	O
selection	O
effects	O
of	O
attention	O
have	O
been	O
especially	O
interested	O
in	O
amplitude	B-Application
variation	O
of	O
the	O
N1	B-Algorithm
because	O
amplitude	B-Application
differences	O
are	O
believed	O
to	O
represent	O
a	O
gain	O
control	O
mechanism	O
(	O
see	O
Filtering	O
Paradigm	O
above	O
)	O
.	O
</s>
<s>
For	O
example	O
,	O
because	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
for	O
targets	O
in	O
unattended	O
visual	O
fields	O
is	O
smaller	O
than	O
for	O
targets	O
in	O
attended	O
visual	O
fields	O
,	O
it	O
is	O
believed	O
that	O
attention	O
serves	O
to	O
amplify	O
the	O
processing	O
of	O
sensory	O
inputs	O
from	O
attended	O
locations	O
and	O
suppress	O
sensory	O
inputs	O
from	O
unattended	O
locations	O
.	O
</s>
<s>
Thus	O
,	O
amplitude	B-Application
differences	O
in	O
the	O
N1	B-Algorithm
are	O
useful	O
in	O
providing	O
evidence	O
for	O
whether	O
attention	O
serves	O
to	O
select	O
certain	O
types	O
of	O
sensory	O
stimuli	O
for	O
further	O
processing	O
.	O
</s>
<s>
One	O
of	O
the	O
factors	O
that	O
influences	O
the	O
latency	O
of	O
N1	B-Algorithm
is	O
processing	O
effort	O
:	O
N1	B-Algorithm
latency	O
increases	O
as	O
effort	O
at	O
processing	O
is	O
also	O
increased	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
onset	O
,	O
peak	O
,	O
and	O
offset	O
latencies	O
of	O
the	O
N1	B-Algorithm
occur	O
significantly	O
earlier	O
in	O
response	O
to	O
moving	O
stimuli	O
in	O
a	O
simple	O
detection	O
task	O
vs.	O
an	O
identification	O
task	O
.	O
</s>
<s>
N1	B-Algorithm
is	O
also	O
sensitive	O
to	O
the	O
manipulation	O
of	O
a	O
visual	O
stimulus	O
 '	O
intensity	O
.	O
</s>
<s>
N1	B-Algorithm
's	O
peak	O
latency	O
is	O
shortened	O
as	O
the	O
brightness	O
of	O
stimulus	O
flashes	O
is	O
increased	O
.	O
</s>
<s>
Therefore	O
,	O
it	O
appears	O
that	O
N1	B-Algorithm
latency	O
is	O
affected	O
by	O
perceptual	O
factors	O
,	O
such	O
as	O
flash	O
intensity	O
,	O
as	O
well	O
as	O
the	O
level	O
of	O
attentional	O
demand	O
or	O
processing	O
effort	O
.	O
</s>
<s>
Amplitude	B-Application
differences	O
in	O
the	O
N1	B-Algorithm
have	O
provided	O
evidence	O
that	O
attention	O
allows	O
for	O
more	O
extensive	O
analysis	O
of	O
visual	O
information	O
,	O
such	O
as	O
color	O
and	O
motion	O
.	O
</s>
<s>
It	O
was	O
found	O
that	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
was	O
greater	O
for	O
targets	O
of	O
the	O
correct	O
color	O
and	O
motion	O
when	O
participants	O
were	O
instructed	O
to	O
attend	O
to	O
one	O
side	O
of	O
the	O
visual	O
field	O
versus	O
when	O
they	O
were	O
not	O
instructed	O
to	O
do	O
so	O
.	O
</s>
<s>
As	O
expected	O
,	O
when	O
comparing	O
targets	O
in	O
the	O
attended	O
visual	O
field	O
to	O
targets	O
in	O
the	O
unattended	O
visual	O
field	O
,	O
it	O
was	O
found	O
that	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
was	O
greater	O
for	O
attended	O
(	O
vs	O
.	O
unattended	O
)	O
objects	O
.	O
</s>
<s>
Additionally	O
,	O
although	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
was	O
greatest	O
for	O
targets	O
in	O
the	O
attended	O
visual	O
field	O
and	O
the	O
attended	O
part	O
of	O
object	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
for	O
targets	O
in	O
the	O
unattended	O
portion	O
of	O
the	O
attended	O
object	O
was	O
larger	O
than	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
for	O
targets	O
at	O
an	O
equivalent	O
distance	O
from	O
the	O
locus	O
of	O
attention	O
but	O
on	O
an	O
unattended	O
object	O
.	O
</s>
<s>
More	O
recently	O
,	O
research	O
on	O
the	O
N1	B-Algorithm
has	O
expanded	O
into	O
the	O
processing	O
of	O
socially	O
relevant	O
stimuli	O
.	O
</s>
<s>
ERP	B-Algorithm
research	O
has	O
been	O
useful	O
in	O
understanding	O
how	O
emotion	O
relates	O
to	O
attention	O
because	O
the	O
N1	B-Algorithm
provides	O
a	O
means	O
of	O
examining	O
the	O
significance	O
of	O
emotion	O
in	O
capturing	O
attentional	O
resources	O
.	O
</s>
<s>
For	O
example	O
,	O
in	O
one	O
study	O
,	O
both	O
stimuli	O
that	O
were	O
positively	O
valenced	O
(	O
e.g.	O
,	O
nude	O
person	O
of	O
the	O
opposite	O
sex	O
)	O
and	O
negatively	O
valenced	O
(	O
e.g.	O
,	O
snarling	O
wolf	O
)	O
were	O
shown	O
to	O
elicit	O
greater	O
N1	B-Algorithm
amplitudes	B-Application
than	O
neutrally	O
valenced	O
(	O
e.g.	O
,	O
wrist	O
watch	O
)	O
stimuli	O
.	O
</s>
<s>
Similarly	O
,	O
the	O
valence	O
of	O
interpersonal	O
stimuli	O
has	O
been	O
found	O
to	O
influence	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
.	O
</s>
<s>
Positive	O
stimuli	O
(	O
e.g.	O
,	O
smiling	O
faces	O
)	O
and	O
negative	O
stimuli	O
(	O
e.g.	O
,	O
sad	O
faces	O
)	O
have	O
been	O
found	O
to	O
elicit	O
a	O
greater	O
N1	B-Algorithm
than	O
neutral	O
stimuli	O
(	O
e.g.	O
,	O
neutral	O
faces	O
)	O
.	O
</s>
<s>
The	O
large	O
corpus	O
of	O
studies	O
focused	O
on	O
factors	O
that	O
modulate	O
the	O
amplitude	B-Application
of	O
the	O
visual	B-Algorithm
N1	I-Algorithm
have	O
provided	O
a	O
wealth	O
of	O
evidence	O
suggesting	O
that	O
,	O
while	O
the	O
visual	B-Algorithm
N1	I-Algorithm
is	O
a	O
sensory	O
component	O
evoked	O
by	O
any	O
visual	O
stimulus	O
,	O
it	O
also	O
reflects	O
a	O
benefit	O
of	O
correctly	O
allocating	O
attentional	O
resources	O
and	O
that	O
it	O
is	O
a	O
manifestation	O
of	O
an	O
important	O
sensory	O
gating	O
mechanism	O
of	O
attention	O
.	O
</s>
<s>
When	O
attention	O
is	O
focused	O
on	O
areas	O
of	O
the	O
visual	O
field	O
in	O
which	O
relevant	O
information	O
is	O
presented	O
(	O
vs	O
.	O
evenly	O
distributed	O
across	O
the	O
visual	O
field	O
or	O
focused	O
on	O
an	O
area	O
in	O
which	O
relevant	O
information	O
is	O
not	O
presented	O
)	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
is	O
largest	O
and	O
indicates	O
a	O
benefit	O
of	O
correctly	O
allocating	O
attentional	O
resources	O
.	O
</s>
<s>
Additionally	O
,	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
is	O
believed	O
to	O
represent	O
a	O
sensory	O
gain	O
control	O
mechanism	O
because	O
focusing	O
attention	O
on	O
one	O
area	O
of	O
the	O
visual	O
field	O
serves	O
to	O
increase	O
the	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
to	O
relevant	O
perceptual	O
information	O
presented	O
in	O
that	O
field	O
(	O
vs	O
.	O
the	O
other	O
visual	O
field	O
)	O
,	O
and	O
thus	O
facilitates	O
further	O
perceptual	O
processing	O
of	O
stimuli	O
.	O
</s>
<s>
Additionally	O
,	O
research	O
on	O
the	O
visual	B-Algorithm
N1	I-Algorithm
suggests	O
that	O
spatial	O
and	O
object	O
attention	O
serve	O
as	O
an	O
early	O
selection	O
mechanism	O
that	O
influences	O
the	O
selection	O
of	O
other	O
perceptual	O
features	O
(	O
e.g.	O
,	O
color	O
,	O
motion	O
)	O
for	O
further	O
processing	O
.	O
</s>
<s>
The	O
amplitude	B-Application
of	O
the	O
N1	B-Algorithm
is	O
largest	O
for	O
perceptual	O
features	O
in	O
attended	O
(	O
vs	O
.	O
unattended	O
)	O
locations	O
and	O
on	O
attended	O
(	O
vs	O
.	O
unattended	O
)	O
objects	O
,	O
providing	O
evidence	O
that	O
perceptual	O
features	O
are	O
only	O
selected	O
for	O
further	O
perceptual	O
processing	O
if	O
they	O
are	O
in	O
attended	O
locations	O
or	O
on	O
attended	O
objects	O
.	O
</s>
<s>
Lastly	O
,	O
the	O
visual	B-Algorithm
N1	I-Algorithm
has	O
also	O
been	O
interpreted	O
to	O
reflect	O
a	O
discrimination	O
process	O
that	O
takes	O
place	O
within	O
the	O
locus	O
of	O
attention	O
.	O
</s>
<s>
As	O
compared	O
with	O
conditions	O
that	O
simply	O
require	O
a	O
response	O
,	O
the	O
N1	B-Algorithm
component	O
is	O
enhanced	O
in	O
conditions	O
that	O
require	O
a	O
differentiation	O
between	O
classes	O
of	O
stimuli	O
.	O
</s>
<s>
The	O
N1	B-Algorithm
may	O
,	O
therefore	O
,	O
reflect	O
a	O
discrimination	O
mechanism	O
that	O
is	O
applied	O
to	O
an	O
attended	O
spatial	O
area	O
.	O
</s>
<s>
Identifying	O
the	O
neurological	O
sources	O
of	O
ERP	B-Algorithm
components	O
based	O
on	O
the	O
topographical	O
distribution	O
of	O
the	O
N1	B-Algorithm
on	O
the	O
scalp	O
is	O
especially	O
difficult	O
because	O
the	O
number	O
of	O
potential	O
sources	O
(	O
referred	O
to	O
as	O
dipoles	O
)	O
,	O
orientations	O
,	O
and	O
magnitudes	O
that	O
can	O
produce	O
the	O
topographical	O
distribution	O
of	O
the	O
N1	B-Algorithm
,	O
like	O
any	O
other	O
ERP	B-Algorithm
component	O
,	O
is	O
theoretically	O
infinite	O
.	O
</s>
<s>
This	O
problem	O
of	O
working	O
from	O
the	O
topographical	O
distribution	O
of	O
ERP	B-Algorithm
components	O
to	O
identifying	O
neural	O
sources	O
,	O
is	O
referred	O
to	O
as	O
the	O
Inverse	O
problem	O
.	O
</s>
<s>
Although	O
the	O
neural	O
generators	O
of	O
the	O
N1	B-Algorithm
are	O
not	O
definitively	O
known	O
,	O
evidence	O
suggests	O
that	O
the	O
N1	B-Algorithm
does	O
not	O
originate	O
in	O
the	O
primary	O
visual	O
cortex	O
,	O
but	O
instead	O
from	O
multiple	O
generators	O
in	O
the	O
occipito-parietal	O
,	O
occipito-temporal	O
,	O
and	O
(	O
possibly	O
)	O
frontal	O
cortex	O
.	O
</s>
