The Nature of Sensation
Psychology, Unit 2
Objectives
Define Sensory and Perception
Know the basic process of sensation
Understand what is meant by “sensory
thresholds”
Apply the concept of subliminal
perception to your daily life
Understand the importance of
psychological research in the area of
extrasensory perception
What is sensation and perception?
Sensations- are the raw data of
experience (smells, sights, sounds,
tastes, balance, touch and pain)
Perception- the mental process of
sorting, identifying, and arranging
sensations into meaningful
patterns
The Basic Process of Sensation
Step 1: there must be a source of
energy (light waves, vibration,
etc)
Step 2: this energy stimulates the
appropriate receptor cells
RC: a specialized cell that
responds to a type of energy.
Step 3: RC’s send the energy “message”
along sensory nerves to the cerebral
cortex
RC’s, sensory nerves and areas of the
cerebral cortex are coded to send
messages through energy specific
channels
EX: sound can only be received by specific “sound
RC’s,” which send sound to specific sensory nerves,
which communicate the sound to a specific area of the
brain! (Push on eyelids- GENTLY)
Exit Ticket
1. Contrast sensation and
perception
2. Summarize the process of
sensation (IN COMPLETE
SENTENCES)
Sensory Thresholds
Absolute threshold: the least
amount of energy that can be
detected as a stimulation at least
50% of the time
Adaptation: adjustment of senses
based the level of stimulation they
are receiving (eyes adjusting to the
dark in a movie theater)
Change and the Senses
We most notice change in our
surroundings (light to dark, silence to
sound)
Difference threshold/just noticeable
difference (JND): the smallest change in
stimulation that can be detected 50% of
the time
Extrasensory Perception
ESP: a sensation NOT related to our
know senses
Déjà vu, telepathy, clairvoyance
Studied by parapsychologist
Valid area of study, but widely
criticized
Many p’s believe its possible, but they
also see some “psychics” as un truthful
and therefore useless in experimentation
Subliminal Perception
Studies in labs have shown subliminal
messages to have an effect of the
behavior of those exposed to them
While it can cause an effect it is not an
absolute effect
Subliminal messages in a campaign
will not force all Americans to vote for
that candidate
Exit Ticket
1. Compare and contrast absolute and
difference threshold
2. Provide a personal example of sensation
adaptation
3. Describe a personal example of
subliminal messaging
4. Why is parapsychology so controversial