Chapter 5 Sensation and Perception Review

Describe the types of global image features that help people perceive the gist of a visual scene.

*Degree of naturalness -Oceans and forests have textured zone and undulating contours *Degree of openness -Oceans have a visible horizon line and contain few objects *Degree of roughness -Smoothe scenes like ocean contain fewer small elements *Degree of expansion Color

What were some of the "challenges of object perception" described in the text and lecture?

-Ambiguous stimulus on receptors -Hidden & blurred objects -Different viewpoints -Unclear reasons for chances in darkness and lightness

How well did Thomas Naselaris & coworkers (2009) brain activity "decoder" identify complex visual scenes using structural coding alone and using structural+semantic encoding?

-Structural Encoder: good job of matching the structure of target image, but poor job of matching meaning of target image -Semantic encoding: improves performance

Why are the Gestalt "laws" more accurately described as "heuristics"?

Are mental shortcuts for solving for solving problems

Describe the characteristics associated with the figure and those associated with the ground. List some of the characteristics of a figure that cause a particular part of the figure to be more likely to be seen as the "figure" (see pages 104-105).

Characteristics of figure -Object that stands out -Contour belongs to figure -More "thing" like -More memorable than ground -Seen as being in front of ground Characteristics of background -Is a ground -More uniformed

How well did Kamitani & Tong (2005) brain activity "decoder" identify the orientation of grating stimuli?

Decoder accurately predicted the orientations

describe the Gestalt principles

Determine by organizing principles which determine how elements in a scene become grouped together

Relationship between the development of the FFA and children's face

FFA is smaller in an 8 year old when compared to FFA of an adult's

examples of these principles from figures and descriptive examples

Good Continuation Pragnanz Similarity Proximity Common Fate Common Region Uniform Connectedness Meaningfulness- familiarity Synchrony

Brain activity and seeing - use of binocular rivalry in studies such as Sheinberg & Logothetis (1997) on page 115 of your textbook

Images in the left and right eye can't be fused together so the brain must pick

What does the acronym KISS stands for ?

Keep it simple sally

Infant face perception. What did Ian Bushnell (2001) discover about 2-day-old infants' ability to recognize their mother's face?

Look at mothers face 63% of the time when compared to strangers

Describe the basics of Palmer's (1975) study. What was the main concept taken from this research?

Main concept: Identify object, that best fits the scene, from previous knowledge

Describe some of the physical regularities in the environment that aid perception.

Regularly occurring physical properties of the environment Ex: more vertical + horizontal lines than oblique (angled) orientation

Describe the "inverse projection problem".

Retinal image can be caused by an infinite number

Describe the perceptual effects of ambiguous figure ground drawings.

Separate figure from ground

Describe the Theory of Unconscious Inference - the likelihood principle

Some perceptions are the result of unconscious assumptions we make about the environment Likelihood principle Perceive the object that is most likely to have caused the patterns of stimuli received

Pragnanz

Stimulus pattern is seen in such a way that the resulting structure is a simple as possible (olympic circles)

Are faces special?

Yes b/c they are pervasive in environment, establish one's identify, provided info about one's mood, neurons that respond selectively to faces

Uniform Connectedness

connectedness region of the same visual properties (light ,color, is perceived as a single unit etc.)

Synchrony

elements occurring at the same time are seen as belonging together

Common Region

elements that are in the same region appear to be grouped together

Meaningfulness- familiarity

items form groups if they appear familiar or meaningful

Similarity

similar things appear to be grouped together

Good Continuation

the tendency of a person to perceive forms of similar shape, form, color, pattern, and other attributes in group.

Proximity

things that are near each other appear to be grouped together

Common Fate

things that move in the same direction appear to be grouped together Connected region perceived as single unit