Today’s Goals 1. To understand Gestalt concepts and principles, such as figure-ground, continuity, similarity, proximity, closure, 2. To understand binocular and monocular depth cues and apply monocular depth cues. HOMEWORK: Prepare for unit exam/midterm.

Today’s Goals 1. To apply Gestalt concepts and principles, such as figure-ground, continuity, similarity, proximity, closure. 2. To explain binocular and monocular depth cues and apply monocular depth cues. HOMEWORK: 1. Prepare for quiz on perception. 2. Read pages Complete assignment posted on my website

Perception

Perceptual Organization Gestalt: “whole” Gestalt: “whole” emphasizes humans’ tendencies to integrate pieces of information into meaningful wholes. emphasizes humans’ tendencies to integrate pieces of information into meaningful wholes. “The whole is greater than the sum of its parts” “The whole is greater than the sum of its parts”

Gestalt form perception principles continuity simplicity, connectedness, and more……

Perception Visual Capture: tendency for vision to dominate the other senses. Visual Capture: tendency for vision to dominate the other senses. zXi5bCikCc (Brain Games, part 2: 4:15 through McGurk) zXi5bCikCc (Brain Games, part 2: 4:15 through McGurk) zXi5bCikCc zXi5bCikCc

Phi phenomenon - illusion created when two or more adjacent lights blink on and off in succession, creating the perception of movement (lighted signs, illusions) kY_FeYhttp:// kY_FeY (Brain Games part 1, 13:13) _IGV7F8 _IGV7F8 (Pink Dots)

Depth Perception ability to see objects in three dimensions. Allows us to estimate distance. ability to see objects in three dimensions. Allows us to estimate distance.

Visual Cliff Experiments Click on link above to view the visual cliff experiment The Visual Cliff Experiment Depth perception in infants??

Depth Cues Binocular vs. monocular depth cues Binocular vs. monocular depth cues

Types of Depth Cues Binocular Cues: depth cues that rely on the use of two eyes. Binocular Cues: depth cues that rely on the use of two eyes. Retinal (Binocular) Disparity: images of an object from the two eyes differ. The closer the object, the larger the difference (disparity.) finger sausage Retinal (Binocular) Disparity: images of an object from the two eyes differ. The closer the object, the larger the difference (disparity.) finger sausage Convergence: extent to which the eyes converge inward when looking at an object; brain keeps track to measure distance. Convergence: extent to which the eyes converge inward when looking at an object; brain keeps track to measure distance.

Types of Depth Cues Monocular Cues: distance cues available to either eye alone (1 eye). Art techniques Monocular Cues: distance cues available to either eye alone (1 eye). Art techniques Monocular cues included in text reading: Monocular cues included in text reading: Relative size Relative size Interposition Interposition Relative Height/Height in the Visual Field Relative Height/Height in the Visual Field Linear Perspective Linear Perspective Light and Shadow Light and Shadow Relative Motion/ Motion Parallax and Relative Motion/ Motion Parallax and

Additional monocular cues: Additional monocular cues: Relative Clarity: hazy object seen as more distant Relative Clarity: hazy object seen as more distant Texture gradient: nearby =coarse & detailed, distant = smooth and less detail Texture gradient: nearby =coarse & detailed, distant = smooth and less detail Relative Brightness: closer objects appear brighter Relative Brightness: closer objects appear brighter

What Cues Do You See? Group activity

Perceptual Constancy Perceptual Constancy: perceiving objects as unchanging despite changes in retinal image Perceptual Constancy: perceiving objects as unchanging despite changes in retinal image color color shape shape size size (Brain Games, part 1 1:50)

Interplay Between Perceived Size and Distance Using monocular cues for distance can often cause us to perceive information incorrectly. Using monocular cues for distance can often cause us to perceive information incorrectly.

Diameter of Circles Are the Same

Muller-Lyer Illusion

Monocular Cue?

What Cues Do You See? Group activity

How many Legs?

Perceptual Constancy Perceptual Constancy: perceiving objects as unchanging despite changes in retinal image Perceptual Constancy: perceiving objects as unchanging despite changes in retinal image color color shape shape size size

Interplay Between Perceived Size and Distance Using monocular cues for distance can often cause us to perceive information incorrectly. Using monocular cues for distance can often cause us to perceive information incorrectly.

Diameter of Circles Are the Same

Muller-Lyon Illusion Which is longer?

Muller-Lyon Illusion

Muller-Lyer Illusion

Cultural Influences on Depth Perception

Impossible Image

Impossible Staircase

Day 2

Sensory Deprivation and Perception Blind Person Example Blind Person Example Some aspects of perception might be innate Some aspects of perception might be innate Others involve experiences Others involve experiences Critical period for development of sensation and perception Critical period for development of sensation and perception

Sensory Deprivation and Perception Kittens raised without exposure to horizontal lines later had difficulty perceiving horizontal bars.

Perceptual Adaptation Perceptual Adaptation Perceptual Adaptation (vision) ability to adjust to an artificially displaced visual field (vision) ability to adjust to an artificially displaced visual field prism glasses prism glasses

Today’s Goals To understand how our experiences and expectations influence perception. To understand how our experiences and expectations influence perception. To understand the importance of perceptual constancies. To understand the importance of perceptual constancies. To understand major visual illusions. To understand major visual illusions. HW: Study for perception quiz/midterm exam.

Perceptual Constancy The ability to perceive an object as the same even as the illumination and retinal image changes. The ability to perceive an object as the same even as the illumination and retinal image changes. Shape Shape Size Size Color Color

PERCEPTION GAMES!! Numbers Word game Punctuate the following: TIME FLIES I CANT THEYRE TOO FAST What do these letters spell? FOLKCROAKSOAK

Perceptual Interpretation Perceptual Set: a mental predisposition to perceive one thing and not another. Perceptual Set: a mental predisposition to perceive one thing and not another. What you see in the middle is influenced by if you looked at bottom or the top What you see in the middle is influenced by if you looked at bottom or the top Schemas Schemas

Lochness Monster or a Tree Trunk?

Perceptual Set

Context Effects

Perceptual Set Affects Other Senses Perceptual Set also affects other senses like audition. Perceptual Set also affects other senses like audition. Ex: eel is on the wagon vs. eel is on the orange. Ex: eel is on the wagon vs. eel is on the orange. CONTEXT MATTERS! CONTEXT MATTERS! Rat Man Rat Man Lyrics Lyrics

Muller-Lyon Illusion Which is longer?

Muller-Lyon Illusion

ATTENTION Today’s goal: To understand the role of attention in perception. HW: 1. STUDY FOR MIDTERM!!!! 2. Read pages of text. TAKE NOTES on concepts, terms, people in notebook.

Perception: Attention Selective Attention: The ability to focus on one stimulus at a time and block out others;

Selective Attention: Allows us to function in a world filled with many stimuli; reduces sensory overload Pop out: stimuli that are so powerful or distinct that they draw our eye and demand our attention Pop out: stimuli that are so powerful or distinct that they draw our eye and demand our attention

Pop Out

Selective Attention The most famous example to illustrate selective attention is known as the “cocktail party effect.”

Testing Selective Attention

Selective Inattention Inattentional blindness Inattentional blindness Change blindness Change blindness Choice blindness Choice blindness

Choice Blindness

Attention DVD

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Perception and the Human Factor Human Factors Psychologists- explore how people and machines interact and how machines and environments can be adapted to human behaviors Human Factors Psychologists- explore how people and machines interact and how machines and environments can be adapted to human behaviors

Is there Extrasensory Perception? Extrasensory Perception: claim that perception can occur apart from sensory input. Extrasensory Perception: claim that perception can occur apart from sensory input. Astrological predictions, psychic healing, communication with the dead Astrological predictions, psychic healing, communication with the dead Telepathy- mind to mind Telepathy- mind to mind Clairvoyance- perceiving remote events Clairvoyance- perceiving remote events Precognition- perceiving future events Precognition- perceiving future events Psychokinesis- mind over matter Psychokinesis- mind over matter Example- light as a feather stiff as a board Example- light as a feather stiff as a board

Is there Extrasensory Perception? Parapsychology: study of paranormal phenomenon, including ESP and psycho kinesis. Parapsychology: study of paranormal phenomenon, including ESP and psycho kinesis. Research Research Psychics not accurate Psychics not accurate More predictions- police work More predictions- police work Vague predictions Vague predictions Lottery Lottery No experiment has EVER produced a convincible demonstration of ESP No experiment has EVER produced a convincible demonstration of ESP

Perceptual Organization Gestalt: an organized whole. Gestalt: an organized whole. Gestalt psychologists emphasize humans’ tendencies to integrate pieces of information into meaningful wholes. Gestalt psychologists emphasize humans’ tendencies to integrate pieces of information into meaningful wholes. Things are not seen as sum of parts but immediately as wholes. Things are not seen as sum of parts but immediately as wholes. “The whole is greater than the sum of its parts” “The whole is greater than the sum of its parts”

Gestalt

Gestalt Psychology Grouping: the perceptual tendency to organize stimuli into coherent groups Grouping: the perceptual tendency to organize stimuli into coherent groups Some Grouping Principles: Some Grouping Principles: Proximity Proximity Similarity Similarity Continuity Continuity Closure Closure Connectedness Connectedness Simplicity Simplicity

Perceptual Organization Figure-Ground Relationship: tendency to organize information into objects (figure) that stand out from their background(ground) Figure-Ground Relationship: tendency to organize information into objects (figure) that stand out from their background(ground)

Figure Ground Relationship

Proximity: tendency to group nearby figures together

Gestalt Principles: Proximity

Similarity: tendency to group figures that are similar

Gestalt Principles: Similarity

Continuity: tendency to perceive continuous patterns

Gestalt Principles: Continuity

Closure: tendency to fill in the gaps in visual information.

Gestalt Principles: Closure

Connectedness: spots, lines and areas are seen as unit when connected

Gestalt principles: Simplicity

Illusionary Contours: We constantly filter information so it makes sense to us. Adding edges, boundaries, etc. which are not there.

Types of Depth Cues Monocular Cues: distance cues that are available to either eye alone (1 eye). Art techniques Monocular Cues: distance cues that are available to either eye alone (1 eye). Art techniques Monocular Cues Includes: Monocular Cues Includes: xRelative size: smaller image is more distant xRelative size: smaller image is more distant xInterposition: closer object blocks distant object xInterposition: closer object blocks distant object Relative Clarity : hazy object seen as more distant Relative Clarity : hazy object seen as more distant Texture gradient: nearby =coarse & detailed, distant = smooth and less detail Texture gradient: nearby =coarse & detailed, distant = smooth and less detail xRelative Height/Height in the Visual Field: higher objects seen as more distant xRelative Height/Height in the Visual Field: higher objects seen as more distant

xRelative Motion/ Motion Parallax : closer objects seem to move faster & in opposite direction; distant objects move in the same direction and xRelative Motion/ Motion Parallax : closer objects seem to move faster & in opposite direction; distant objects move in the same direction and xLinear Perspective: parallel lines converge with distance xLinear Perspective: parallel lines converge with distance Relative Brightness: closer objects appear brighter Relative Brightness: closer objects appear brighter xLight and Shadow: nearby objects reflect more light to our eyes; dimmer of 2 objects seems farther away. xLight and Shadow: nearby objects reflect more light to our eyes; dimmer of 2 objects seems farther away.