Presented by:- Group 5

Ayesha SardarNida-tul-ain Satti

Maryam NisarAyesha MujahidMarzia SafdarMahnoor Khalil

Presented to:- Ma’am Tabassum

TOPIC OF PRESENTATION

WHAT IS PERCEPTION??? “Perception can be defined as our recognition and interpretation of sensory information.”

.FOR EXAMPLE:-Lets look at our perception of words. Each letter of alphabet is in itself a singular letter. When we perceive words, we think of them as one singular unit that is made up of smaller parts called LETTERS. It is through this organization of letters into words that we are able to make something meaningful. That is, we perceive an entire word and this word has a specific meaning that can be found in a dictionary.

Although intimately related, sensation and perception play two complimentary but different roles in how we interpret our world. Sensation refers to the process of sensing our environment through touch, taste, sight, sound and smell. This information is sent to our brains in raw form where perception comes into play. Perception is the way we interpret these sensations and therefore make sense of everything around us.

And

Perception is the way how a person understands something

Reality is the truth and actual existence of something

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PROCESSES OF THE PERCEPTION

Perception’s three basic processes: Selection Organization Interpretation

CONSTANCY• Objects change in

our eyes constantly as we or they move….but we are able to maintain constant perception

• Shape Constancy• Size Constancy• Brightness

Constancy

SHAPE CONSTANCY

It is recognition that an object remains the same size even though the retinal image of the object changes

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Flat Front View

3D Side View

SIZE CONSISTENCY The perceived size of an object remains

constant, despite changes in its retinal size

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BRIGHTNESS CONSISTENCY

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We perceive an object as having a constant brightness even while its illumination varies

Types Of Perception :

Form Perception

Depth Perception

FORM PERCEPTION

Form perception is the recognition of objects in a particular form within a certain environment.

An object is perceived by the retina as a two dimensional image, but the image can vary for the same object in terms of the context with which it is viewed, the apparent size of the object, the angle from which it is viewed, how illuminated it is, as well as where it resides in the field of vision.

FORM PERCEPTION: THE GESTALT LAWS OF ORGANIZATION

Figure and ground The organization of the visual field into objects

(the figures) that stand out from their surrounding (the ground)

Grouping The perceptual tendency to organize stimuli

into coherent groups Grouping principles: proximity, similarity,

continuity, closure etc

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Organizational Behavior / Perception

Figure and ground

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GESTALT PSYCHOLOGY•Gestalt psychologists focused on how we GROUP objects together.•We innately look at things in groups and not as isolated elements.•Proximity - group objects that are close together as being part of same group.•Similarity - objects similar in appearance are perceived as being part of same group.•Continuity - objects that form a continuous form are perceived as same group.•Closure - like top-down processing…we fill gaps in if we can recognize it.

DEPTH PERCEPTION

WHAT IS DEPTH PERCEPTION

The visual ability to perceive the world in three dimensions (3D) though the images formed on our retina are two dimensional.Eleanor Gibson and Richard walk regarded the ability of depth perception as innate.

DEPTH PERCEPTION The ability to see

three dimensional space and to accurately judge distances

Depth cues for depth perception: binocular cues, monocular cues

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EXAMPLEEVEN though this painting is on a flat canvas you still percieve it in 3D. Why???

Types of depth or distance perception 1)Binocular cues2) Monocular cues

Binocular CuesBinocular depth information is dependent on information from both eyes, not one.. Binocular depth cues are clues about distance based on the differing views of the two eyesThere are two types of binocular cues :- Retinal disparity convergence

Retinal Disparity:- The image your right eye sees is different than your left eye because they are a small distance apart. The image you see using both eyes is the two images merged.

Convergence  Because the two eyes converge on an object when we are viewing it, the brain can use the angle of convergence as a cue to how far away that object is.

For example ,

Monocular cues:-Cues received by one eye.

When we have to judge a person wheter he is 100 feet or 100 yards away, the retinal disparity is slight, we have to depend on monocular cues.Monocular cues are the following:-

1) Relative size2)Linear perspective3)Overlap and interposition of objects4)clearness of details5)Change in colour6)Relative height7)Relative brightness8)Accommodation of the eye

1) Relative sizeAccording to law of visual angle,

.As an object moves farther

away its image

becomes smaller.

The object itself is of

same size.....

BUTThe size of retinal images is shortening relatively.

ExampleIf we see the same cars from the top

of Minar-e-Pakistan or Shahi mosque, the apparent size

of those cars looks smaller.

2)Overlap or interposition of objects

If one thing covers other, the covered thing is

perceived farther and the coverer seems nearer .

ExampleIf a tree covers

some position of a house , the tree is perceived nearer

and house farther.

Light and shadow

Nearby objects reflect more light to our eyes. Thus, again two similar objects, the dimmer one seems further away

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Relative heightNear objects are low in the visual field; more distant ones are higher up

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Relative sizeIf separate objects are expected to be of the same size, the larger one are seen as closer

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Activity