psyc unit 3 perception 2

7/30/2019 Psyc Unit 3 Perception 2

1/42

Unit 3- Perception


2/42

Sensation Stimulation of sensory receptorsTransmission of sensory information to the

CNS Process of detecting and encoding stimulus

energy into the world. Sensory receptors are located in the

sensory organs e.g. eyes, ears and skin.


3/42

Sensation Stimulation of the senses is an automatic

process resulting from sources of energy

e.g. light, sound or presence of chemicalsfor smell of taste.

It is then transmitted to the CNS throughelectric impulses.


4/42

PerceptionThe brains process of organising and

interpreting sensory info to give it meaning.

Not automatic but an active process Begins with sensation but also reflects ones

experiences and expectations as it makessense of sensory stimuli.


5/42

Concepts Relating to Perception1.Absolute Threshold

2.Difference Threshold

3.Signal-detection theory4.Sensory adaptation

5.Selective Attention

6. Illusion

7.Perceptual organisation


6/42

Concepts Relating to Perception

Absolute threshold the weakest amount of

stimulus that a person can distinguish fromno stimulus at all.The minimum amount of energy that we

can detect . What does it take to activate a

specific sensory system?


7/42

Concepts Relating to PerceptionAbsolute Thresholds

1. Vision a candle flame viewed from about

30 miles on a clear dark night.2. Hearing a watch ticking from 20 feet

away

3. Taste 1tsp. of sugar dissolved in 2

gallons of water.


8/42

Concepts Relating to PerceptionDifference Threshold the minimum

difference in intensity required between two

sources of energy so that they can beperceived as different. Smallest difference requires to discriminate

one stimulus from another.


9/42

PERCEPTION

Concepts Relating to PerceptionDifference Threshold Is it the same or different?

The stronger the initial stimulus, thegreater a change must be for us to noticeit


10/42

Concepts Relating to PerceptionSignal Detection Theory - concept thatsensitivity to sensory stimuli depends on a

variety of factors besides the physicalintensity of the stimulus and the sensoryabilities of the observer e.g. fatigue,expectancy, alertness, motivation etc.


11/42

Concepts Relating to PerceptionSensory Adaptation- process by which we

become more sensitive to stimuli of low

magnitude and less sensitive to stimuli thatremain the same e.g. background noises oradapting to a dark room.

Sensitization (positive adaptation)

becoming more sensitive to stimulation . Desensitization (negative adaptation)-

becoming less sensitive to stimulation


12/42

Concepts Relating to PerceptionSelective Attention - the focus ofconsciousness on a particular stimuli while

ignoring others. Also shiftable i.e. moving your attention

from one stimuli to another if necessary. Influenced by ones motivation and

interests.


13/42

Concepts Relating to PerceptionIllusion - sensation that gives rise to

misrepresentation

Are incorrect but not abnormal Occurs when two objects produce exactly

the same retinal image but are perceived asdifferent.


14/42

Concepts Relating to PerceptionPerceptual Organization process by which

we organise or make sense of sensoryimpressions.

Guided by principles or Gesalt laws of:1.Proximity - nearness, the perceptual

tendency to group together objects that arenear to one another.

2.Similarity perceptual tendency to grouptogether objects that are similar inappearance.


15/42

Concepts Relating to PerceptionPerceptual OrganizationLaws of Proximity & Similarity


16/42

Concepts Relating to PerceptionPerceptual Organization

3.Continuity the tendency to perceive a

series of points or lines as having unity.4.Common fate - the tendency to perceive

elements that move together as belongingtogether.


17/42

Concepts Relating to PerceptionPerceptual OrganizationLaws of Continuity


18/42


Laws of Common Fate Components in sound act together.They tend to start and finish togetherThey tend to change in pitch or intensity

together.


19/42

Concepts Relating to PerceptionPerceptual Organisation

5. Closure the tendency to perceive abroken figure as being complete or whole.

6. Smallness - Smaller areas tend to be seenas figures against a larger background


20/42

Concepts Relating to PerceptionPerceptual OrganizationLaws of Closure


21/42

Concepts Relating to PerceptionPerceptual OrganizationLaws of Smallness


22/42


Figure Ground Perception-thetendency to organise the perceptual field

into stimuli that stand out (figure) andthose that are left over (ground)


23/42

Factors Influencing Perception

1.Motives

2.

Interests3.Person (self)

4.Target

5.Context


24/42

Factors Influencing Perception1.Motives unsatisfied needs or motives

stimulate individuals and may exert astrong influence on their perceptions.

2. Interests focus of our perception isinfluenced by our interest.

Individuals interest differ so what one

notices in a situation can differ from whatanother perceives


25/42

Factors Influencing Perception3.Person the characteristics of a person

influences how they perceive a stimuli. Themajor characteristics include:

a.Attitudesb.Moodc. Self conceptd.Cognitive structure

e.Expectationsf. Past experiencesg.Motives


26/42

Factors Influencing Perception4.Target characteristics of a target affects

how it is perceived e.g. physical appearance motions, shapes, colours, attractiveness,

facial expressions, similarity, proximity etc.

5.Context - the situation between theobserver and the target also affects the waya stimuli is perceived e.g. social settings,time, work setting


27/42

Illusion Provides insight into how our perceptual

process works. Occurs when two objects produce exactly

the same retinal image but are perceived asdifferent.

Mller-Lyer Illusion

Two sets of arrows that exhibit the Mller-Lyer optical illusion. The set on the bottomshows that all the shafts of the arrows areof the same length


28/42

Illusion

Perceptual Constancy

Mller-Lyer Illusion


29/42

IllusionPerceptual Constancy Objects are perceived as constant or

unchangingThe tendency for perceived objects to give

rise to very similar perceptual experiencesin spite of wide variations in the conditionsof observation (retinal image).


30/42

IllusionPerceptual Constancy Size constancy recognising that that an

object remains the same size even thoughthe retinal image of the object haschanged.

Shape constancy - recognising that anobject remains the same even though itsorientation to us changes.


31/42

Illusion


Size/Shape Constancy


32/42

Illusion


Size Constancy


33/42

IllusionPerceptual Constancy

Shape Constancy


34/42


Shape Constancy


35/42


3. Brightness Constancy the recognitionthat an object retains the same degree ofbrightness even though different amountsof light fall on it.

4. Colour Constancy - the tendency for acolor to look the same under widelydifferent viewing conditions


36/42


Brightness Constancy


37/42


Colour Constancy


38/42

Illusion Experience is very important in resolving

the discrepancies between a retinal imageof an object and its actual size, shape or

brightness.


39/42

Stereotyping Assumptions that we make based on prior

experiences. An exaggerated belief associated with a

category. Perceptual shortcuts:

1. First impression

2. Viewing people as constant

3. Blaming the victim4. Halo effect

5. Just like me


40/42

StereotypingCharacteristics Fixed rigid ideas

Oversimplification of a category or groupof people Not supported by reasonable evidence Can be favourable or unfavourable

Driven by motives


41/42

StereotypingCauses Socialisation

Media Cognitive Process Role Models Figures of authority


42/42

StereotypingStrategies to Correct Incorrect Perceptions Accept that people are different Practice active listening Provide feedback Own your behaviour/feelings Avoid stereotyping Use inclusionary language Distinguish between overgeneralisations and

factual evidence

psyc unit 3 perception 2

Documents