sensation perception l.
Skip this Video
Loading SlideShow in 5 Seconds..
Sensation & Perception PowerPoint Presentation
Download Presentation
Sensation & Perception

Loading in 2 Seconds...

play fullscreen
1 / 19

Sensation & Perception - PowerPoint PPT Presentation

  • Uploaded on

Sensation & Perception. What is the difference?. Sensation. Detection of physical energy emitted or reflected by physical objects Sense organs eyes, ears, tongue, nose, skin, internal body tissues Without sensations, we would not experience reality. Perception.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

Sensation & Perception

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
sensation perception
Sensation & Perception
  • What is the difference?
  • Detection of physical energy emitted or reflected by physical objects
  • Sense organs
    • eyes, ears, tongue, nose, skin, internal body tissues
  • Without sensations, we would not experience reality
  • A set of mental operations that organize sensory input into meaningful patterns
  • Perception allows us to interpret our sensations and thus reality
how many senses
How many Senses?
  • Five?
  • Actual many more
the riddle of separate sensations
The Riddle of Separate Sensations
  • Sense receptors
    • specialized cells in the sense organs that convert physical energy from the environment into electrical energy to be transmitted as nerve impulses to the brain
johannes muller
Johannes Muller
  • doctrine of specific nerve energies
    • Different sensory modalities exist b/c signals received by the sense organs stimulate nerve pathways leading to different brain areas
    • Because different brain areas are stimulated, different sensations are experienced
    • Synesthesia
      • Stimulation of one sense evokes sensation of another
functional codes
Functional Codes
  • Doctrine doesn’t account for variations within a sense
    • Seeing gold versus yellow
  • Functional code account for this
    • Within a sense certain neurons fire or don’t, fire fast or slowly, or in a pattern to create different sensations
measuring the senses
Measuring the Senses
  • Psychophysics
    • How the physical properties of stimuli are related to our psychological experience of them
absolute thresholds
Absolute thresholds
  • Smallest quantity of energy that can be reliably detected 50% of time
  • Very sharp senses
    • candle flame on a clear, dark night from 30 miles away!)
difference thresholds
Difference thresholds
  • just noticeable differences (jnds)
  • Smallest difference in sensory stimulation that can be detected reliably between two stimuli
  • The larger, or more intense, stimulus 1 is, the greater the jnd needs to be
signal detection theory
Signal-detection theory
  • Theory that accounts for response biases in absolute threshold and difference threshold measurements
  • An observer’s response in a detection task is divided into a sensory process (which depends on the stimulus’s intensity) and a decision process (which is influenced by the participant’s response bias)
signal detection theory13
Signal-detection theory
  • A mathematical formula separates estimates of a person’s sensory process and decision process, yielding a predicted value for one’s true sensitivity to a particular stimulus
sensory adaptation
Sensory Adaptation
  • When stimulation is unchanging or repetitious, sensory receptors “tire” and fire less frequently, resulting in a decline in sensory responsiveness
  • Sensory adaptation to touch/pressure
    • (the feel of the clothes on your body)
    • smell (of one’s perfume or cologne)
we rarely adapt to visual stimuli
We rarely adapt to visual stimuli
  • because our eyes are constantly moving back and forth
we never completely adapt
We never completely adapt
  • to very intense stimuli (e.g., noxious fumes, intense pain)
sensory deprivation
Sensory deprivation
  • Absence of normal sensory stimulation
    • Heron (1957)—visual, auditory, an tactile stimulation was deprived, resulting in disorientation, feelings of edginess and confusion, and many reports of hallucinogenic visions
don t oversimplify
Don’t oversimplify!!—
  • sensory deprivation may be a form of relaxation for some, but torture for others
  • it all depends upon the context
    • meditation/relaxation versus solitary confinement in prison
sensory without perceiving
Sensory without Perceiving
  • Selective attention is necessary to focus on and filter out numerous sensory stimuli from being consciously perceived all at once
  • “Cocktail party phenomenon”