2nd Nose You can use either hand, but this is the left hand, as seen from the back.]]Crossyourmiddle fingerbehind your index finger. The index finger is sometimes calledthepointer finger-- it's the finger right next to yourthumb. The fingers should betouching near, but not at, the tips. It doesn't matter whichhandyou use. Bring your crossed fingers to the tip of your nose
Bring your crossed fingers to the tip of your nose.Place your fingers sothat the tip of your nose is in the small space or gap between the twofingertips. If you're using your right hand, the right side of the tip of yourmiddle finger and the left side of the tip of your index finger should betouching your nose; if you're using your left hand, this will be reversed. Youwill probably notice a strange sensation, as though you have two noses. Run your crossed fingers slowly up and down the bridge of your nose
Run your crossed fingers slowly up and down thebridge of your nose.If you haven't already felt thetwo-noses sensation, you likely will now, as yourmotor brain is tricked into thinking that each fingeris focused on a separate nose.[2] Chapter 6:Perception Perception Selective Attention: the focus ofconsciousawareness on aparticular stimulus. Selective Attention The most famousexample to illustrateselective attention isknown as thecocktail partyeffect. concentration-deaf_n_ html?utm_hp_ref=science&icid=maing- grid7%7Cmain5%7Cdl5%7Csec1_lnk3%26pLid%3D171994 Testing Selective Attention remember this activity? http://www.echalk.co.uk/amusements/OpticalIllusions/motionBli ndness/motionBlindness.html
Haircut Brain Games color Perception Visual Capture:refers to thetendency for visionto dominate theother senses. Perceptual Organization
Gestalt:an organized whole. Gestalt psychologistsemphasize humans tendenciesto integrate pieces ofinformation into meaningfulwholes. Things are not seen as sum ofparts but immediately aswholes. Top-downProcessing You may startto seesomething inthis picture ifwe give yourbrain someconcepts toapply: tree sidewalk dog Dalmatian Click to reveal sidebar and hints one by one. Gestalt Perceptual Organization
Figure-GroundRelationship: tendency to organizeinformation into objects(figure) that stand outfrom theirbackground(ground) Figure Ground Relationship Gestalt Psychology Grouping:the perceptual tendency toorganize stimuli into coherent groups Grouping Principles: Proximity Similarity Continuity Closure Connectedness Proximity: tendency to group nearby figures together Similarity: tendency to group figures that are similar Continuity: tendency to perceive continuous patterns Closure: tendency to fill in the gaps in visual information. Closure Connectedness: spots, lines and areas are seen as unit when connected Grouping examples Which grouping principle do you see in this picture? Illusionary Contours:We constantly filter information so it makes sense to us. Depth Perception Depth Perception:theability to see objects inthree dimensions. Allows us to gaugedistance. Visual Cliff: illustrated that crawlinginfants and newbornsperceive depth. Visual Cliff: A Test of Depth Perception
Babies seem to develop this ability at crawling age. No animation. Instructor: as a preview of figuring out how we perceive depth, note that the pattern on the floor looks more condensed (and thus farther away) to the infant than the identical pattern on the table. The infant can perceive this difference as depth/height and see a danger of falling. Note that the ability to perceive glass as solid does not appear to be as innate as the fear of the cliff. Even newborn animals fear the perceived cliff. Types of Depth Perception
Binocular Cues:depth cues that rely on theuse of two eyes. Examples of Binocular Cues: Retinal Disparity: idea that images of anobject from the two eyes differ.The closerthe object, the larger the difference(disparity.) Convergence:extent to which the eyesconverge inward when looking at an objectthat brain keeps track of to measuredistance. Types of Depth Perception
Monocular Cues:distance cues that areavailable to either eye alone.Often used inart. Monocular Cue: Relative Size
We intuitively know to interpret familiar objects (of known size) as farther away when they appear smaller. No animation. Monocular Cue: Interposition
Interposition: When one object appears to block the view of another, we assume that the blocking object is in a position between our eyes and the blocked object. No animation. Monocular Cues: Relative Clarity
Hazy object seems more distant Monocular Cues: Texture
Coarse = close Fine = distant Monocular Cue: Relative Height
We tend to perceive the higher part of a scene as farther away. This scene can look like layers of buildings, with the highest part of the picture as the sky. If we flip the picture, then the black part can seem like night sky because it is now highest in the picture. Click to show bullets and example. Monocular Cues: Relative Motion
When we are moving, we can tell which objects are farther away because it takes longer to pass them. A picture of a moon on a sign would zip behind us, but the actual moon is too far for us to pass. No animation. A great animated example can be found at This depth perception cue is often referred to as motion parallax. It is used by many animals that dont have the benefit of binocular cues because their eyes are on the sides of their heads. It is called relative motion; when we are moving, the objects we pass can appear to be moving in the opposite direction, and the farther objects dont move as fast. Motion Perception We perceive motion in many ways.
Objects moving toward us We perceive this motion by watching the changing apparent size of an object. Objects moving to one side We perceive relative motion, although we often judge huge objects inaccurately. In what way?Why? Objects traveling in a more complex path, such as in an arc through the air coming toward us Baseball players, and even dogs, can run right to where a fly ball is going to land by keeping the ball in a constant apparent position in the sky. Click to reveal bullets. Instructor: an option for introducing this slide is connecting this concept to the relative motion monocular cue. The cues of relative motion that help us see distance can also be used in reverse; if we already know the size and thus the distance of objects, we can more accurately judge motion of ourselves or objects around us. First bullet: This is the growing/approaching Frisbee effect. Second bullet: We judge huge objects to be moving more slowly, perhaps because we are ready to judge them as closer, smaller objects covering less distance. Monocular Cues: Linear Perspective and Interposition
The flowers in the distance seem farther away because the rows converge. Our brain reads this as a sign of distance. No animation. Instructor: see if students can notice one other monocular cue for depth perception evident in this picture...interposition. The flowers in the very front (bottom of the frame) partially block the view of other flowers, and the whole hill of flowers appears to block the view of the hill in the background. Tricks Using Linear Perspective
These two red lines meet the retina as being the same size However, our perception of distance affects our perception of length. Click to bring bottom line up. The way our brain changes the perception of length in this case is called the Ponzo illusion, first demonstrated by Italian psychologist Mario Ponzo in 1913. The two [rods/bars/logs] are the same size on screen, but our eyes tend to see one as larger because linear perspective makes its location on the train tracks seem farther away. Monocular Cues: Shading Effects Relative Brightness
Shading helps ourperception ofdepth. Does the middlecircle bulge out orcurve inward? How about now? Click to invert the image and show the hollow as a hill. Light and shadow create depth cues.
No animation. Monocular Cue? Monocular Cue? Monocular Cue? What Cues Do You See? How many Legs? Perceptual Constancy color shape size
Perceptual Constancy:perceiving objects as unchangingdespite changes in retinal image color shape size Shape Constancy What shape do you see outlined in red? No animation.
Instructor: you could ask students an intentionally ambiguous question...What shapes do you see outlined in red? If they say rectangle, ask again, no longer referring to the doors. Tell us the names of the red shapes. Then click to fade the doors and reveal that the second and third red shapes are trapezoids. Interplay Between Perceived Size and Distance
Using monocular cues for distance can often cause us toperceive incorrect information. Diameter of Circles Are the Same Spelling test answers:
CONTEXT EFFECT The text at the bottom of the screen will appear on click, and is mean to appear only AFTER you do the spelling test below. Instructor: The point of the test is to demonstrate how context, affected/primed by the previous word you stated, can affect which word they perceived. You can state to students, Six word spelling test!You cannot ask questions; just take a guess and listen for the next word. Write these words down: Double. Pear. (Students may, if double gives them context, write pair.) Apple.Payor. (Students may, when primed by apple, write pear.) Payee.Pair. (Here, students might be confused, or some may write payor.) Spelling test answers: doublepear applepayor payeepair Did context affect which word you wrote? Muller-Lyer Illusion Cultural Influences on Depth Perception Impossible Image Impossible Staircase Warm Up Sensory Deprivation and Perception
Blind Person Example Some aspects of perceptionmight be innate Others involve experiences Critical period fordevelopment of sensation andperception Sensory Deprivation and Perception
Kittens raised without exposure to horizontal lines later had difficulty perceiving horizontal bars. Perceptual Adaptation
(vision) ability to adjust to anartificially displaced visual field prism glasses Perceptual Interpretation
Perceptual Set: a mentalpredisposition to perceiveone thing and not another. What you see in the middleis influenced by if youlooked at bottom or the top Lochness Monster or a Tree Trunk? Perceptual Set Affects Other Senses
Perceptual Set also affects other senses likeaudition. Ex:eel is on the wagon vs. eel is on theorange. CONTEXT MATTERS! Rat Man Lyrics Perception and the Human Factor
Human Factors Psychologists- explore how people and machinesinteract and how machines andenvironments can be adapted to humanbehaviors Is there Extrasensory Perception?
Extrasensory Perception:claim that perception can occurapart from sensory input. Astrological predictions, psychic healing,communication with the dead Telepathy- mind to mind Clairvoyance- perceiving remote events Precognition- perceiving future events Psychokinesis- mind over matter Example- light as a feather stiffas a board Is there Extrasensory Perception?
Parapsychology:study of paranormalphenomenon, including ESP and psycho kinesis. Research Psychicsnot accurate More predictions- police work Vague predictions Lottery No experiment has EVER produced a convincibledemonstration of ESP Phi Phenomenon Blinking lights give the illusion of motion