SENSATION AND PERCEPTION Sunday, June 02,

SENSATION AND PERCEPTION Sensation is gathering info from the environment via your senses. Perception is understanding what is being sensed! 2

 Humans are credited with five basic senses: Seeing Hearing Smelling Tasting Touching 3 5 SENSES

4 TRY THIS YOURSELF!!!

5 CONT… Our sensory and perceptual processes work together to help us sort out complex images

 Psychophysics: What is the relationship between the physical characteristics of a stimulus and the psychological experience of it?  Sensory physiology: How do sense organs, receptor cells, and neural circuits respond to physical stimuli, to tell our brains what is out there?  Transduction: Stimulus is converted into neural impulses 6 THREE PARTS OF THE PSYCHOLOGY OF SENSATION

PSYCHOPHYSICS:  A study of the relationship between physical characteristics of stimuli and our psychological experience with them. 7 PSYCHOPHYSICS Physical WorldPsychological World lightBrightness soundVolume pressureWeight SugarSweet

 Stimulus: A source of physical energy that produces a response in a sense organ.  Sensation: A process by which an organism responds to a stimulus.  Intensity: The strength of a stimulus. 8 SENSATION….IMP. CONCEPTS

Vision (sense of sight) sensitive to LIGHT ENERGY Auditory (sense of hearing) stimulated by SOUND ENERGY Olfaction (sense of smell) stimulates our nostrils by CHEMICAL ENERGY Gustation (sense of taste) Tactile (skin senses for pressure, temperature, pain) THERMAL ENERGY 9 THE HUMAN SENSES (NAMES…)

 Threshold—refers to a point above which a stimulus is perceived and below which it is not perceived. It determines when we first become aware of a stimulus. Absolute Threshold Difference threshold Subliminal 10 THRESHOLDS

 Absolute Threshold: The smallest amount of physical intensity by which a stimulus can be detected.  Difference threshold (just noticeable difference): The smallest detectable difference between two stimuli. OR “The minimum difference a person can detect between any two stimuli” Example: An artist might detect the difference between two very similar shades of color 11 CONT…

 Subliminal: Below one’s absolute threshold for conscious awareness  People have different thresholds, because some people have better hearing than others, and some people have better visions than others 12 CONT…

 Psychologists tend to view sensation as biological process and perception as cognitive process.  There are two factors of perception 1.Objective Factors 2.Subjective Factors 13 FACTORS OF PERCEPTION

There are a number of characteristics of stimuli that influence our perception. 1.Intensity 2.Size 3.Distinct & Striking 4.Movement 5.Novelty 6.Duration 7.Repetition 8.Abrupt Change 14 OBJECTIVE FACTORS

Sometimes, perception is determined not only by the physical characteristics of stimuli but by the characteristics of the perceiver. These are 1.Motives or needs 2.Interests & values 3.Past experience 4.Age 5.Preparatory set 6.Social & cultural factors 15 SUBJECTIVE FACTORS

Proximity Things close to one another are grouped together Closure The brain tends to fill in gaps to perceive complete forms 16 GESTALT PRINCIPLES

Similarity Things that are alike are perceived together Continuity Anything which extends itself into space in the same shape, size and color without a break is perceived as a whole figure. 17 CONT…

 Knowledge and experience are extremely important for perception, because they help us make sense of the input to our sensory systems.  In the example above, you did not stop to read every single letter carefully. Instead, you probably perceived whole words and phrases. 18 TRY TO READ THE FOLLOWING PASSAGE:

19 WHAT ARE FICTIONS? When you see something that is not there. E.g. the white triangle

When an object can be seen in more than one way. Do you see a man playing the saxophone or a woman’s face? 20 WHAT ARE AMBIGUOUS FIGURES?

 Without the ability to organize and interpret sensations, life would seem like a meaningless jumble of colors, shapes, and sounds. A person without any perceptual ability would not be able to recognize faces, understand language, or avoid threats. 21 WORK…