PSY100H1 Lecture Notes - Lecture 11: Necker Cube, General Idea, Spreading Activation
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Lecture 11 - 04-01-13
Chapter 10 Visual Knowledge
long-term visual memory
the diversity of knowledge
Can you picture this...
"picture a puppy rolling in the snow..."
On a day to day basis, we do a lot of visual imagery. How many windows do we have in our
condo/house? We can picture it. How do we have this picture that isn't really a picture, how do
we bring this up? They're done on a regular basis. Another is: was so and so in class the other
day? We don't know that information right off the bat but we can picture the class. Another is:
buying new clothes, we can hold the jeans/sweater in front of us and visualize how we look in
Francis Galton (1883)
Ask them to visualize an object and then ask them to report as much information as they could.
Most people could do something like that. What they reported was very different, very broad
range of self reports - detailed images, cats, colours of the eyes, nails trimmed, etc. Others were
very basic in terms of what they were picturing. The question is: self reports/introspections
aren't always the best articulate way of explaining what they're looking at. Is it the case that the
reporting is off? Or the case that what they're imagining in their mind is different? Detail versus
Another type of studies were looked at. These kinds differ because they add some objectivity to
what people are picturing. We call these chronometric studies. We ask participants to
manipulate the image. Do something with it that should take a different amount of time based
on how they're imagining this image to be and then we time it. It's a more objective type of
view. Observe how long the manipulation takes.
Kosslyn (1976): premise was this: if you think about a cat, generally the things that come up
about the animal or what you would normally talk about in how it differentiates from other
animals are claws and whiskers; heads and ears may not the first pieces of information that
comes to mind. When you have to draw a picture of the cat, you usually draw the head first, not
a defining feature, that's the biggest object that you would draw to begin the process in terms
of a picture. Defining feature is not prominent pictures versus non-defining features but
prominent pictures. They had participants answer whether the cat had x or y. Subjects were
quicker at identifying the cat has a head when asked first to visualize a cat. It fits more with the
way in which people would draw an image. People are actually looking a picture in their head.
The reverse was also done, just to think about the cat. Quicker at defining these defining
Image-scanning procedure. Kosslyn et al. (1978)
A map is shown, asked to memorize the map. Memorize it to the extent that they can draw it
from memory. The question then is posed to them, in this case; there's a straw hut and a well.
You already memorized the picture. Imagine a little dot from straw hut to the well and tell me
when you get there. And then they would say now tell me from straw hut to the tree, and then
to the rocks at the top. The distance between the two objects, as the distance increases, more
time is taken. More than likely, people are actually picturing this map and thinking about this
dot travelling across it, just as if the map was in front of them, and their eyes follow the
trajectory. The results show that the effects are consistent/robust. Imagined distance
correspond to real distance. Follow up studies have been done: follow up from A to B in your
house, etc. The further away they're traveling, the longer it takes. Something similar is imagine
that we're asked to picture a car sitting here, and then a mouse sitting next to the car. We are
then asked if the mouse has whiskers. We would be able to confirm or deny but it may take a
little bit of time whereas if we are asked a mouse next to a quarter and asked if the mouse has
whiskers, we are quicker at identifying. The quarter is more proportional to the mouse in size as
opposed to the car. We must zoom-in in the former example just like we're looking closer at the
picture. The latter, we're in the same frame as the detail so we are quicker to respond. Supports
that mental pictures/images are there. Another study is the mental-rotation task (Friedhoff). Are
these two objects the same? Generally we would be looking at the speed at identifying if they're
the same. We would rotate either clockwise or counter clockwise. In the latter set of objects, we
must rotate to a larger degree. The results of these studies show that it takes subjects longer to
identify these latter ones. It correlates with the amount of time of spinning the actual object. It's
not just two dimensional but something to do with three dimensional. The greater the spin or
the angle needed to spin, the longer it takes for people to do it. It's less like pictures but more
Mental images are pictures or sculptures. There's also the counter argument that you have
some expectation for the researcher. Most people want to please the researcher and get the
right results. The majority of people want to do that. When people are asked the question: how
long does it take you to get here or rotate this, there's some characteristic being demanded of
them that they try to fulfill. This is not the case though. Even if you tell them what they're there
for, they still take the same amount of time.
If we're asked to picture what something sounds and looks like, auditory versus visual, there are
perceptual mechanisms in place that seem to interfere with each other if the modality is the
same. Why would we want to look at something like this? It was mentioned that the brain is
very efficient in how it utilizes the resources that are there. This is a way to begin to look at
whether there is a competition of resources based on what they're asked to visualize and what
they're asked to respond to. There should be some conflict if they're using the same resources
(visualize and visual task), if not, it should be easy. This research looked at auditory versus visual.
There is interference when modalities are the same. There is overlap in picturing something in
mind's eye and seeing something physically in front of you.
We would say that imagery can interfere with perception (mismatching). It can also facilitate
perception. One way to think about this is that if your task of visualization is congruent with
what you're asked to picture in mind's eye, visual stimulus in picturing something, and it's
similar, it actually helps it, it's a facilitation effect. I.e. if primed first, it helps you respond to that
picture as a stimulus.
Lecture outline visual imagery long-term visual memory the diversity of knowledge. On a day to day basis, we do a lot of visual imagery. We don"t know that information right off the bat but we can picture the class. Another is: buying new clothes, we can hold the jeans/sweater in front of us and visualize how we look in them. Ask them to visualize an object and then ask them to report as much information as they could. What they reported was very different, very broad range of self reports - detailed images, cats, colours of the eyes, nails trimmed, etc. Others were very basic in terms of what they were picturing. The question is: self reports/introspections aren"t always the best articulate way of explaining what they"re looking at. These kinds differ because they add some objectivity to what people are picturing.