WLU PS262 Lesson Notes (Introduction to Perception) 2026
complete update textbook version |summary notes Wilfrid
Laurier University
1.1 Introduction: Studying Perception
If you love optical illusions, you are going to love this course. If you ever get a job where
you have to design anything, you will both love and need what you learn in this course. If
you ever work with people who are ill, elderly or disabled, the knowledge you gain from this
course may help you understand the challenges they face, and the treatment and support
options available for them. Welcome to the wonderful world of human perception, where
nothing is as it seems, and nothing is as simple as it may have seemed to you before.
The study of perception is the study of the organs and processes that connect us with the
outside world. At any given waking moment, you are awash in a sea of information, and
your brain seemingly miraculously weaves all of this together into a seamless experience of
the world around. Consider where you are sitting right now:
• Your visual system is using information carried on light waves to tell you what
objects are nearby, and what the words on the screen are. This information
may cause you to click a button on the mouse, or it may cause you to look up
to wave at a passing friend.
• Your auditory system tells you if anyone is calling your name, or if someone
has just sent you a text message.
• Your sense of touch tells you if you have pushed the computer mouse off the
edge of the table, or if you are perched on the edge of your chair and may fall
off.
• If you are snacking then your senses of smell and taste give you lots of
information as well.
,Phew!
The five senses: seeing, hearing, touch, taste, and smell, connect us to our world. They are
the basis of everything we experience, yet are tremendously complicated to understand. So,
what are some reasons some people study perception?
, • Please note that I refer to figures and illustrations throughout
these online lesson notes.
• Some of the figures I discuss are included in the online notes, or
accessible online via web links.
• However, some important figures we discuss online are from the
Goldstein textbook for this course.
• Keep your textbook handy when you read online notes, to look up
each figure when it is mentioned.
1.1.1 Studying perception is interesting
First off, studying perception is, to many people, interesting — you can understand an
incredibly important part of yourself and how you work. Also, the fact that you are studying
something you do all the time means you can experiment on yourself at times when
studying perception. This can be a lot of fun, because there are many tricks and
demonstrations you can do at home. Some of them even make good party tricks! You also
learn about what it means to be human, and how our senses combine to construct our
experience of life.
Senses are our only connection with the environment, our only way to find out what's
around us.
Question: Let me ask you — besides our senses, what other ways could information from
environment get in to our brains?
(When I ask this question during a lecture for the campus course, I typically receive silence,
which is the right answer. In other words, outside of the fictional movie "The Matrix",
there are no other ways for information from the world to get into our brains,
other than via our senses!)
, The "brain in a vat" idea illustrates the
volume and complexity of sensory
information we process. How much
information would a computer need to
generate to convince a disembodied "brain in
a vat" that it is living in a normal body, in a
world that responds normally to its actions?
(The answer is - a lot!)
Outside science fiction, no brain can be wired
up this way. No device can engage our
perceptual systems the same way our own
sense organs do. That said, we are able to
design powerful sensory prosthetic devices,
like implants to boost hearing, that interface
fairly directly with our sensory nervous
systems.
Might it one day be possible to communicate
a whole sensory world through electrodes
directly into the brain? Could we send a probe up to Mars and actually fully feel like we are
really there by wiring in all the relevant information? Study perception and decide for
yourself if you think such technology might be in our future!
(Public domain image: Wikimedia Commons.)
1.1.2 Studying perception is useful
Studying perception is enormously practical in today's day and age. We live in an intensively
designed environment. Sensory interfaces connect us to an expanding world of technology
and communications. Whether you are designing webpages, choosing stationary for
wedding invitations, improving your photography skills, refining your taste in food or drink,
developing new technologies, designing posters, accessorizing outfits, recording music or
podcasts, or participating in helping to create any object in our technological, connected
world, understanding human perception is a key success factor.
Designers who have a scientific understanding of perception will stand out from their peers,
and today we all have to work as designers from time to time. Most of us will have occasion
to design documents, flyers, speeches, to compose emails, and do countless other small
design tasks. The more you know about human perception, the more you can help shape
your communications in ways that are both appealing and useful.
complete update textbook version |summary notes Wilfrid
Laurier University
1.1 Introduction: Studying Perception
If you love optical illusions, you are going to love this course. If you ever get a job where
you have to design anything, you will both love and need what you learn in this course. If
you ever work with people who are ill, elderly or disabled, the knowledge you gain from this
course may help you understand the challenges they face, and the treatment and support
options available for them. Welcome to the wonderful world of human perception, where
nothing is as it seems, and nothing is as simple as it may have seemed to you before.
The study of perception is the study of the organs and processes that connect us with the
outside world. At any given waking moment, you are awash in a sea of information, and
your brain seemingly miraculously weaves all of this together into a seamless experience of
the world around. Consider where you are sitting right now:
• Your visual system is using information carried on light waves to tell you what
objects are nearby, and what the words on the screen are. This information
may cause you to click a button on the mouse, or it may cause you to look up
to wave at a passing friend.
• Your auditory system tells you if anyone is calling your name, or if someone
has just sent you a text message.
• Your sense of touch tells you if you have pushed the computer mouse off the
edge of the table, or if you are perched on the edge of your chair and may fall
off.
• If you are snacking then your senses of smell and taste give you lots of
information as well.
,Phew!
The five senses: seeing, hearing, touch, taste, and smell, connect us to our world. They are
the basis of everything we experience, yet are tremendously complicated to understand. So,
what are some reasons some people study perception?
, • Please note that I refer to figures and illustrations throughout
these online lesson notes.
• Some of the figures I discuss are included in the online notes, or
accessible online via web links.
• However, some important figures we discuss online are from the
Goldstein textbook for this course.
• Keep your textbook handy when you read online notes, to look up
each figure when it is mentioned.
1.1.1 Studying perception is interesting
First off, studying perception is, to many people, interesting — you can understand an
incredibly important part of yourself and how you work. Also, the fact that you are studying
something you do all the time means you can experiment on yourself at times when
studying perception. This can be a lot of fun, because there are many tricks and
demonstrations you can do at home. Some of them even make good party tricks! You also
learn about what it means to be human, and how our senses combine to construct our
experience of life.
Senses are our only connection with the environment, our only way to find out what's
around us.
Question: Let me ask you — besides our senses, what other ways could information from
environment get in to our brains?
(When I ask this question during a lecture for the campus course, I typically receive silence,
which is the right answer. In other words, outside of the fictional movie "The Matrix",
there are no other ways for information from the world to get into our brains,
other than via our senses!)
, The "brain in a vat" idea illustrates the
volume and complexity of sensory
information we process. How much
information would a computer need to
generate to convince a disembodied "brain in
a vat" that it is living in a normal body, in a
world that responds normally to its actions?
(The answer is - a lot!)
Outside science fiction, no brain can be wired
up this way. No device can engage our
perceptual systems the same way our own
sense organs do. That said, we are able to
design powerful sensory prosthetic devices,
like implants to boost hearing, that interface
fairly directly with our sensory nervous
systems.
Might it one day be possible to communicate
a whole sensory world through electrodes
directly into the brain? Could we send a probe up to Mars and actually fully feel like we are
really there by wiring in all the relevant information? Study perception and decide for
yourself if you think such technology might be in our future!
(Public domain image: Wikimedia Commons.)
1.1.2 Studying perception is useful
Studying perception is enormously practical in today's day and age. We live in an intensively
designed environment. Sensory interfaces connect us to an expanding world of technology
and communications. Whether you are designing webpages, choosing stationary for
wedding invitations, improving your photography skills, refining your taste in food or drink,
developing new technologies, designing posters, accessorizing outfits, recording music or
podcasts, or participating in helping to create any object in our technological, connected
world, understanding human perception is a key success factor.
Designers who have a scientific understanding of perception will stand out from their peers,
and today we all have to work as designers from time to time. Most of us will have occasion
to design documents, flyers, speeches, to compose emails, and do countless other small
design tasks. The more you know about human perception, the more you can help shape
your communications in ways that are both appealing and useful.
