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PROFESSOR: This is our first introductory meeting

of the course, which is 9.04.

And we are going to cover vision and audition in this course,

and there are going to be two of us lecturing.

My name is Peter Schiller, and this is Chris Brown.

And I will be talking about the vision portion,

and Chris will be lecturing about the auditory portion.

Now, what I'm going to do is I'm going

to hand out the syllabi that we have, in this case,

for the first half of the course.

And that we are going to discuss in some detail

today for the first half of the lecture,

and Chris is going to discuss it for the second half.

So that is the basic plan for today.

And I will go through some of the basic procedures and issues

that we may want to deal with at this very introductory portion.

So first of all, let me talk about the reading assignments.

If you have the handout, they are ready for you.

If you look at the second page, that's

where we have the assigned readings for the vision

half of the course.

Now, for that half of the course,

the top eight assignments are all articles

in various journals.

We don't have a textbook for this portion of the course.

And then in addition to the assigned readings,

we have recommended readings that are listed there.

And then another important factor

that is listed there-- let me first

say that the lectures will be put on Stellar, in most cases,

after each lecture.

And in addition, the videos that we are now recording

will also become available, but they will not

be available until well after each lecture.

So I would advise each of you to come to the lectures

rather than hoping to read the assigned material only

or to eventually look at the videos.

The reason I'm telling you this is

that our analysis has shown that those students who

attend the lectures regularly get

much better grades on the exams than the students who do not.

So I strongly will urge all of you

to come to as many lectures as you possibly can.

Now, the additional requirement that you're

going to have for this course is to write two research reports,

one for vision and one for audition.

And the assigned written report that you need to put together

is in a paper at the bottom of the second page.

In this case, it's going to be a paper that

was written quite some years ago,

a very important and remarkable paper that has been published

by Oster and Barlow, as you can see.

And the task for you will be to not just report

what they had reported, because that's repetitious,

but to do a bit of research and write

about what has been discovered since the remarkable findings

that these two people had made at the time.

All right.

So that's the research report.

And then I want to specify the exams.

We are going to have a midterm exam,

and the exact date for this has already been set on October 23.

All right?

But as I say, you can find this, and I

will specify that in more detail in just a minute.

And then we are going to have a final exam

at the end of the term.

The exact date for this, as always at MIT,

will not have been set until probably sometime in November.

So now let me also specify the grade breakdown.

I think that's important for all of us.

The written report for each half of the course--

there's going to be one report, as I've already said,

for vision and one for audition--

and that will constitute 10% of the grade for each.

And the midterm exam, this constitutes 25%.

The final exam constitutes 55% of the overall grade.

And in that, 15% will be on vision and 40% on audition.

So if you add that up, you can see that vision and audition

are set up to be exactly equally weighed for the exams.

MICHELLE: Hi.

I'm Michelle.

I'll be helping the professors, especially with [INAUDIBLE].

PROFESSOR: So I'm Chris Brown, and I'm one of the instructors.

I'll be teaching the second half.

And my research is on two areas, brain stem auditory reflexes,

like the startle reflex and the middle ear muscle reflex.

And I also work on animal models of the auditory brain stem

implant, which is a neural prosthesis that's

used in deaf individuals.

PROFESSOR: All right.

And I'm Peter Schiller, and I work on the visual system.

And I'm a professor here in our department.

So that's very nice.

Thank you for the introductions.

And I hope, you guys, we all get to know each other.

I'm very impressed that there's so many seniors here.

That's actually unusual.

I don't remember having this high a percentage

of seniors in the class.

That's really very nice, very nice.

OK.

So now we are going to talk, for the first part

of today's lecture, about what aspects of visual processing

we are trying to understand and, therefore,

what we are going to try to cover

in this course in terms of topics.

OK?

So first of all, what we are going

to do for several lectures is to talk about the layout

and organization of the visual system itself.

Most of it we will discuss as it applies to higher mammals,

in particular monkeys and primates and humans.

Then we are going to talk about specific aspects

of visual processing.

We're going to try to understand how we adapt in vision,

and, very interestingly, how we are

able to perceive colors and process them accurately.

Another fascinating topic is how we

are capable of analyzing motion.

That's a complex, very interesting topic,

as is depth perception.

And the reason depth perception is particularly

interesting is because, as you know,

the retinal surface is essentially

a two-dimensional arrangement.

And yet from whatever falls on these two dimensions

in the left and right eyes, somehow the brain

needs to convert to be able to see the third dimension.

And as a result, several mechanisms

have evolved to accomplish that, and we

are going to discuss them.

Then, again, another very complex topic

is how we can recognize objects.

Perhaps the most complex of those

is our incredible ability to recognize faces.

And that is highlighted, of course,

by the fact that if you look at more simple organisms,

like, I don't know, monkeys, they all look the same to you.

But human beings, who are actually

more similar to each other than perhaps monkeys are,

we are really capable of telling them

apart and readily recognize them over long periods of time.

So it's a very interesting topic.

And yet another topic that we will discuss

is how we make eye movements.

As you probably know, or you're aware of,

that we are constantly moving your eye.

You make saccadic eye movements about three times a second,

thousands of times a day, hundreds of thousands of times,

to be able to see things clearly in the world.

So we are going to try to understand

how that incredible ability has evolved

and how it is realized by the brain.

OK.

So now to look at exactly how we are going to cover this,

let me go through this.

During the next lecture, which is September 9,

we are going to look at the basic layout of the retina

and the lateral geniculate system,

as well as how the visual system in general is wired.

Then on September 11, we're going

to look at the visual cortex, then

at the ON and OFF channels, so-called,

that you'll realize what they are once we talk about it.

And then there's another set of channels

that originates in the retina, which

are the midget and parasol channels.