Chapter 5: Sensation and Perception Flashcards
Transduction
conversion from sensory stimulus energy to action potential
What are the five senses?
Vision, audition, gustation, olfaction, somatosensation
What are the other senses?
- balance- vestibular sense
- body position and movement- proprioception and kinesthesia
- pain- nociception
- temperature- thermoception
absolute threshold
the minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time (how dim can a light be)
Subliminial messages
messages that are presented below the threshold for conscious awareness
JND
- how much difference in stimuli is required to detect a difference between them
- changes depending on stimulus intensity
- goes hand in hand with the Weber’s law
Weber’s law
- the difference threshold is a constant fraction of the original stimulus.
- the principle that states that the just-noticeable difference between two stimuli is a function of the magnitude of the original stimulus.
- This means that the larger the original stimulus, the larger the just noticeable difference needs to be for it to be detected.
- For example, for weights, if the initial weight magnitude is low, adding smaller weights will be more easily detected than if the initial weight magnitude is high.
Perception
is the way sensory info is organized, interpreted, and consciously experienced
Bottom-up processing
refers to sensory info from a stimulus in the environment driving a process (occurs when we sense basic features of stimuli and then integrates them)
Top-down processing
refers to the knowledge and expectancy driving a process (occurs when previous experience and expectations are first used to recognize stimuli)
Sensation is…perception is…
sensation is a physical process whereas perception is psychological
Sensory adaption
we get adapted so we don’t perceive stimuli that remain relatively constant over prolonged periods of time
Inattentional blindness
is the failure to notice something that is completely visible because the person was actively attending to something else and didn’t pay attention to other things
Signal detection theory
is the ability to identify a stimulus when it is embedded in a distracting background because of a certain motivation
Amplitude
is the distance from the center line to the top point of the crest or the bottom point of the trough
frequency
refers to the number of waves that pass a given point in a given time period and is often expressed in terms of hertz or cycles per second (long wavelengths = low frequency
What is the order of the visible spectrum from highest to lowest frequency?
Gamma ray, x ray, uv, visible, infrared, microwave, and radio
light wavelength is associated with
- perception of color
- red: longer wavelength
- greens: intermediate wl
- blues and violet: shorter wl
amplitude of light waves is associated with
- with our experience or brightness of color (longer amp = brighter)
frequency of a sound wave is associated
with our perception of that sound’s pitch (higher freq = higher pitch sound)
Loudness of a given sound is closely associated
with the amp of wave (larger amp = louder sounds, and loudness is measured in decibels)
Timbre
refers to a sound’s purity and its is affected by the complex interplay of frequency and timing of sound waves
Light waves are transmitted…
across the cornea and enter the eye through the pupil
Cornea
-is a transparent covering over the eye which serves as a barrier between the inner eye and the outside world
- involved in focusing light waves that enter the eye
Pupil
- is a small opening in the eye through which light passes and its size can change
- high light levels = small pupil size
- controlled by the muscles that are connected to the iris which is the colored portion of the eye
Lens
- a curved, transparent structure that serves to provide additional focus and is attached to muscles that can change its chape to aid in focusing light that can change its shape to aid in focusing light that is reflected from near or far objects
fovea
- a small indent on the back of the eye part of the retina which in normal sighted people the lens will focus images perfectly on
- condensed with photoreceptor cells that are called cones which are light detecting/work best in bright conditions and ability to perceive color (plus provide spatial awareness)
Rods
- are concentrated throughout the remainder of the retina and work well in low light conditions and can’t perceive color (night vision) as well as help with vision of our periphery