Introduction to PSYB51: Perception & Cognition
x Sensation & Perception
-sensation would rather be the early part of perception... looking at the receptors for e.g. in the
eye or ear
- Perception itself is then more of the cognitive aspect of it
Æ ,W¶VGLIILFXOWWRPDNHDFOHDUFXWVHSDUDWLRQ± LW¶VPRUHOLNHDFRQWLQXXP
³:KDWLVUHDO"+RZGR \RXGHILQHUHDO",I\RX¶UH talking about what you can feel,
what you can smell, what you can taste and see, then real is simply electrical signals
interpreted by your brain. This is the world that you NQRZ´
Neo in The Matrix, 1999
Æ So whatever we learn about the world is somehow transformed into neural signals and
somehow processed by the brain.
x Outline for lecture 1
x Early Philosophy of Perception
x Nativism and Empiricism
x The Dawn of Psychophysics
x Biology of Perception
- Philosophy being one of the important sources where psychology originally comes from.
- Psychophysics = set of tools and methods developed in the 19th century [one
of the major scientific tools you can use in psychology]
Psychophysics = basically trying to describe a phenomenon in psychology in terms of
mathematical things [in a very accurate way]
- For the movie matrix -> the idea originally comes from Plato.
- In his allegory of the cave ±> he describes what he sees as our sense of reality in this
- He said all humans are just like prisoners tied to some wall in a cave ± where they live
their entire life ± they are bonded/chained to it [they NEVER get out] ± they sit there &
GRQ¶WPRYH>VHHSicture on slide]
- From outside: there is light coming from the fire that is casting shadows on the back of
the cave ± which is what the prisoners [humans] see. [shadows of whatever objects are
being carried in front of the fire]
- So the point is that reality as we perceive it according to Plato is extremely limited. We
GRQ¶WSHUFHLYH³the´ reality that is really is out there. [kind of depressing]
- Prof disagrees with Plato.
- Though the idea that our sense of reality is really limited based on what we are able
to perceive is fair enough ± probably accurate. So only what we know of - somehow
we can incorporate into our understanding of reality. Also, we can use all sorts of
machines to expand our reality [e.g. using a microscope to see something that is
really tiny or use some special device to see UV light]
- But there is still the point that there is some limitation in our sense of reality ± that
is determined by what senses we have
- of course all that perception based on our senses are the products of evolution that has to
do with survival mechanisms associated with evolution [which points to the fact that
our perception is pretty much determined by what is really important for us to
perceive ±> which is the current view of things in response to Plato]
- So we perceive things that really matter to us! [ example of slide 15]
x (DUO\3KLORVRSK\RI3HUFHSWLRQFRQW¶G [slide #15]
- 5HPHPEHUSODQWVGRQ¶WKDYHQHXURQV± no muscles!
-so there is sensory input & a response to that [similar in animals/humans]
So in this plant example ± it illustrates that for this plant ± the only way to perceive
this world (importantly at least) is to sense touch ± as it helps the plant to catch flies.
So, the sense of reality for that plant is certainly VERY different from ours ± we
have WAY MORE senses & we use them in a more sophisticated way. But for a
simple plant ± that sense of touch is good enough.
- Not really this depressing idea of Plato ± that we miss so much in reality ± we do miss
something ±> but whether that really is important for us is a different question!
x Some Animals are Able to Sense Stimuli that Humans
-So, animals have the ability to perceive things that humans cannot perceive ± most of
the time that is just b/c they have diff. Types of receptors
e.g. dogs: their olfaction has much richer variety of receptors than humans
Ex: Ben Underwood (uses clicking sounds for navigation) ±> there is the possibility of using
your senses in very special ways.
x (DUO\3KLORVRSK\RI3HUFHSWLRQFRQW¶G [slide#18]
- So our understanding of reality is limited to what we can process in some way.
Î So does our understanding & perception of reality depend only on that?
Î Is there something else to that?
Î Is it only that we perceive the world based on things/energy that somehow interacts
with our senses/receptors?
-ANWER IS NO!!! ± THERE IS SOMETHING ELSE TO
x Heraclitus (540±%&(³<RXFDQQHYHUVWHSLQWRWKHVDPH
- So as you step into the river ±> you influence the river with your step ± so the next time
you step in it, it is totally different!
- & the river is FLOWING = so things change all the time
- Idea that perceiver cannot perceive the same event in exactly the same manner each time
BECAUSE of the FOLLOWING:
([SHULHQFH/HDUQLQJ ± we learn/gain something in terms of experience
$GDSWDWLRQ ± temporary change in some kind of a receptor
Sensation would rather be the early part of perception looking at the receptors for e. g. in the eye or ear. Perception itself is then more of the cognitive aspect of it. ,9870,4/4 4:/013070,14:70 talking about what you can feel, what you can smell, what you can taste and see, then real is simply electrical signals interpreted by your brain. so whatever we learn about the world is somehow transformed into neural signals and somehow processed by the brain. Philosophy being one of the important sources where psychology originally comes from. Psychophysics = set of tools and methods developed in the 19th century [one of the major scientific tools you can use in psychology] Psychophysics = basically trying to describe a phenomenon in psychology in terms of mathematical things [in a very accurate way] For the movie matrix -> the idea originally comes from plato.