FINAL Flashcards
Ecological Approach to Perception
Focus on studying perception in situations where you interact with and move through the environment
Optic flow:
appearance of objects as the observer moves past them
Optic flow is more rapid near the moving observer
The different speed of flow—fast near the
observer and slower farther away—is called
the gradient of flow
The absence of flow at the destination
point is called
the focus of expansion (FOE)
invariant information—
information that remains constant regardless of what the observer is doing or how the
observer is moving
affordances—
information that indicates how an object can be used
More than just recognizing the object
Guide our interactions with it
Another way of saying this is that “potential for action” is part of our perception of an object
action affordance because
it involves both the object’s affordance
(what it is for, for example, “pounding” for a hammer) and the
action associated with it (the grip necessary to hold the hammer
and the movements when pounding in a nail)
visual direction strategy
people keep their body pointed toward their
goal.
spatial updating
process by which people and animals keep track of their position within a surrounding environment while they move
Optic flow provides important information about
direction and speed when walking and this
information can be combined with the visual direction strategy and spatial updating processes to guide walking behaviors
landmarks—
objects on the route that serve as cues to indicate where to turn
decision-point landmarks—
objects at corners where the participant had to decide which direction to turn
non-decision-point landmarks—
objects located in the middle of corridors that provided no critical information
about how to navigate.
parahippocampal
gyrus may automatically be “highlighting” landmarks that
indicate when you should continue going straight, turn right, or turn left, even when you may not remember having seen these
landmarks before
place cells
only fire when an animal is in a
certain place in the environment
area of the environment within which a place cell fires is called
place field
grid cell
provide information about the direction of movement
able to code distance and direction
information as an animal moves, and place cells and grid cells probably work together, because they are connected
with each other.
visuomotor grip cells
involved in both perception (identifying the object and/or its affordances by seeing) and action (reaching for the object and gripping it with the hand)
proprioception—
the ability to sense body position and movement.
mirror neurons—
neurons that respond both when a monkey observes someone else grasping an object such as food on a tray and when the monkey itself grasps the food
audiovisual mirror neurons
respond when a monkey performs a hand action and when it hears the sound associated with this action
The action-specific perception hypothesis states that
people perceive their environment in terms
of their ability to act on it.
cue approach to depth perception
focuses on identifying information in the retinal image that is correlated
with depth in the scene
occlusion
cue that one object is in front of another
Oculomotor.
Cues based on our ability to sense the position of our eyes and the tension in our eye muscles.
Monocular.
Cues based on the visual information available within one eye
Binocular.
Cues that depend on visual information
within both eyes.
oculomotor cues are created by
convergence, the inward movement of the eyes that occurs when we look at nearby
objects, and (2) accommodation, the change in the shape of the lens that occurs when we focus on objects at various distances
The feelings you experience as you move your finger closer are caused by
(1) the change in convergence angle as your eye muscles cause your eyes to look inward,
and (2) the change in the shape of the lens as the eye accommodates to focus on a near object
Monocular cues
They include accommodation,
which we have described under oculomotor cues; pictorial cues, which are sources of depth information in a two dimensional
picture; and movement-based cues, which are
sources of depth information created by movement.
Pictorial cues are
sources of depth information that can be
depicted in a picture
Pictorial cues are
sources of depth information that can be
depicted in a picture
Occlusion occurs when one
object hides or partially hides another from view. The partially hidden object is seen as
being farther away
Cue of relative height
objects with their bases closer to the horizon are usually seen as being more distant. This means that being higher in the field of view causes objects on the ground to appear farther away, whereas being lower in the field of view causes objects in the sky to appear farther away
We use the cue of______when we judge distance based on our prior knowledge
of the sizes of objects.
familiar size
A depth cue related to familiar size is ____.
relative size. According to the cue of relative size, when two objects are known to be
of equal physical size, the one that is farther away will take up
less of your field of view than the one that is closer.
Atmospheric perspective occurs because
the farther away an object is, the more air and particles (dust, water droplets, airborne pollution) we have to look through, so that distant objects appear less sharp than nearer objects and sometimes have a slight blue tin
When a number of similar objects are
equally spaced throughout a scene, they create a _____, which results in a perception of depth, with elements seen as being spaced more closely being perceived
as farther.
texture gradient
Motion parallax occurs when
as we move, nearby objects appear to glide rapidly past us, but
more distant objects appear to move more slowly
stereoscopic vision, which creates stereoscopic depth perception…
created by input from both eyes
Binocular disparity,
the difference in the images on the left
and right retinas, is the basis of stereoscopic vision.
