Chapter 1 Flashcards
sensation
elementary processes
how you detect or process environmental info with your five senses
perception
more complex
higher order mechanisms of awareness
interpreting what you detect using various brain areas
Why is the term “perception” used more than “sensation?”
the difference between sensation and perception is not always obvious; “sensation” does not add to our understanding of sensory experiences
7 steps of the perceptual process
environmental stimulus
principles of transformation and representation
receptors and transduction
neural processing
perception
recognition
action
(+ knowledge)
environmental stimulus
anything in the environment that we observe or detect (distal and proximal)
distal stimulus
something processed (or taken in) in the distance/environment
proximal stimulus
something processed in the body with the five senses
transformation
stimulus changes from distal stimulus to proximal stimulus
representation
stimulus is formed based on receptors and nervous system
sensory receptors
nerve cells or neurons that respond to environmental energy
transduction
change from environmental energy to electrical energy in the brain
neural processing
receptors send electrical signals to brain
electrical signals arrive at primary receiving areas of the lobes and eventually to other areas of the brain
neurons
nerve or brain cells
transmit electrical signals from one neuron to another
change electrical signals to perceive info in the brain
cerebral cortex
2 mm thick layer that contains machinery for creating perceptions
primary receiving areas
where electrical signals arrive in the lobes
electrical signals eventually go to other areas of the brain after primary receiving areas
important to detect perception
4 main lobes in the cerebral cortex
occipital (visual)
temporal (auditory)
parietal (somatosensory)
frontal (motor, receive signals from other senses)
recognition
provides meaning to what we observe
visual form agnosia
can see object (perception) but cannot identify (recognition)
“a-“ - without / “-gnosia” - knowledge
Dr. P brain tumor story
action
to do something with your sensory experiences
necessary for survival
knowledge
info we bring to a situation to perceive a stimulus
rat-man demonstration
demonstrates that our knowledge (patterns) can influence perception
seeing a rat or a man on the demo
what does categorize mean?
name objects, places, and things into an organized way
bottom-up processing
data-based
perceive based on incoming data without prior knowledge
take info one step at a time to process
top-down processing
knowledge-based
perceive based on prior knowledge, experience, and expectation
hard to unlearn
Fechner’s three methods of thresholds
method of limits
method of constant stimuli
method of adjustment
thresholds
detection of limits of our sensory systems
psychophysics
by Gustav Fechner; a way to assess the mind by looking at thresholds
study of relation between mental (psycho-) and stimulus (-physics)
method of limits
experimenter presents stimuli to observer to detect intensity differences in a certain order
absolute and difference thresholds
absolute threshold
minimum detection of a change
complete (do you see blue or not?)
difference threshold
comparing stimuli to see if they differ from each other (is there a difference between the blue colors?)
method of constant stimuli
experimenter randomizes intensities of stimuli
goal of perceptual process
to examine each step + knowledge
three types of relationships of perceptual process
stimulus-behavior
stimulus-physiology
physiology-behavior
stimulus-behavior (+ example)
people presented with something and their observed behaviors are assessed
ex. grating acuity (ability to detect width of gratings)
acuity
sharpness or detailedness
stimulus-physiology (+ example)
people are presented with something and brain activity is assessed
ex. oblique effect (ability to see vertical/horizontal lines better than oblique lines)
physiology-behavior (+ example)
brain activities evaluated by certain behaviors
ex. examining people’s ability to detect different orientations of lines (oblique effect) with physiological measures (fMRI)
cognitive influences on perception
knowledge/top-down processing
other mental activities (cognition, memories, etc.)
other techniques to evaluate perception
magnitude estimation
recognition test
reaction time
phenomenological report
physical tasks and judgments
magnitude estimation
assess how intensity affects our awareness based on how we perceive it
magnitude (how strong of an intensity); estimation (a scale or numbering system to show strength)
ex. carrying weights increases distance perception
recognition test
being able to categorize stimuli
ex. seeing a face or house
reaction time
how long a person responds to a presentation
phenomenological report
ask person to describe perception
“study of an occurrence” report
physical tasks and judgments
acting upon something that is perceived
ex. picking up things and reacting to them
physical vs. perceptual
physical (what is actually there)
perceptual (how we interpret our perception of what is there)
different perceptions goes for all five senses
