Perception
Definition
the organization, identification, and interpretation of sensory information to represent and understand the environment.
Sensation: the process by which our sense organs
receive information from the environment.
we gain information about the properties and elements of the environment helps us navigate and understand the world around us helps us interact w environment helps us survive
Psychophysics is the study of the relationship between the physical aspects of stimuli and our psychological experience of them
Senses - (five senses) proprioception social cues
Absolute threshold: the smallest intensity of
the stimulus that must be present for it to be
detected.
Difference threshold: the smallest level of
stimulation required to sense that a change has
occurred.
Just noticeable difference: The minimum
stimulation required to detect the difference
between the two stimuli.
Adaptation: An adjustment in sensory capacity
following prolonged exposure to stimuli.
top-down processing Perception that is guided by higher-level knowledge, experience, expectations, and motivations
bottom-up processing Perception that consists of the progression of recognizing and processing information from individual components of a stimuli and moving to the perception of the whole.
Gestalt Laws of Perceptual Organisation
Gestalt School ‘the whole is something else than the sum of its parts’ Wertheimer, Koffka, Kohler 20th Century
Gestalt is used in modern German to mean the way a thing has been “placed,” or “put together
CCP and SS are authoritarian Figures - Principles of Gestalt
Continuity Closure Proximity Similarity Symmetry Figure and Ground
illusion
a misrepresentation of a “real” sensory stimulus an interpretation that contradicts objective “reality” as defined by general agreement universal unlike hallucinations real stimuli, wrong interpretation
Monocular and Binocular Cues
flowchart TD
Depth[Depth Perception] ---> a[monocular] & b[binocular]
n[the visual ability to perceive <br> world in 3D <br> ability to gauge <br> how far an object is ]
a --- d[one eye] --- f[bad at depth]
b --- e[two eyes] --- h[diff angles helps]
n --- m[relies on the convergence <br> of both eyes upon a <br> single object]
m --- x[navigating, determing dist, <br> avoiding, etc]
lateral displacement of the eyes that provides
two slightly different views of the same object
allowing STEREOPSIS / two images which helps
us discern depth better
| Mono Cues | Bino Cues |
|---|---|
| Relative Size size constancy - smaller = far | Retinal Disparity |
| Interposition Overlapping objects, object that overlaps = closer | Binocular Convergence |
| Linear Perspective converging of parallel lines | |
| Aerial scattering of blue light; far hill appears blue closer hill more contrast | |
| Light and Shade Highlights and shadows help us understand dimensions of object, where light is coming from, etc | |
| Ponzo Illusion |
Perceptual constancy
refers to the tendency to perceive an object you
are familiar with as having a constant shape, size, and brightness
e.g. - moon illusion
Size Const. Shape Const. Colour Const.
Real and Apparent motion
Apparent Motion -
- Phi Phenomena - bulbs in row, flashing, feels like moving
• Motion after effect (MAE)
• Induced motion - train moving next to you, you feel like you are moving • Autokinetic movement - dark room, singular light, feels like moving