Sensation and Perception Flashcards
(39 cards)
Sensory Adaptation
Our diminishing sensitivity to an unchanging stimulus
Weber’s Law
The principle that, to be perceived as different, 2 stimuli must vary by a constant minimum %
Just noticeable difference (JND)
The minimum difference a person can detect between any 2 stimuli, 50% of the time
Subliminal
Below one’s absolute threshold for conscious awareness
Signal Detection Theory
People’s absolute thresholds vary, there is no single absolute threshold. Predicts when we will detect weak signals, measured as our ratio of “hits” to “false alarms.” Depends on a person’s experience, expectations, motivations and fatigue
Absolute Threshold
The minimum amount of stimulation needed to detect a particular stimulus 50% of the time
Psychophysics
The study of how physical energy relates to our psychological experience
Top-down Processing
Sensory analysis based on our experience and expectations
Bottom-up Processing
Sensory analysis that starts at the entry level
Sensation
Detecting physical energy from the environment and encoding it as neural signals (receiving info. and representing it in our brain).
Vestibular sense
The sense of body movement and position, including the sense of balance. Equilibrium of inner ear
Kinesthesis
The system of sensing the position and movement of individual body parts
Sensory interaction
One sense may influence another
Gate-control Theory
The spinal cord contains a neurological gate that blocks pain signals or allows them to pass to the brain
Nerve deafness
Caused by damage to the cochlea’s receptor cells or to the auditory nerves
Conduction hearing loss
Caused by damage to the mechanical system that conducts sound waves to the cochlea
Volley principle
A group of neural cells can alternate firing–> this way they can achieve a combined frequency above 1,000/sec
Frequency theory
The rate of neural impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense it’s pitch
Place theory
Links the pitch we hear with the place where the cochlea’s membrane is stimulated
Pitch
A tone’s highness or lowness–> depends on frequency
long waves= low frequency= low pitch
short waves= high frequency= high pitch
Frequency
Length of waves
Number of complete wavelengths that pass a point in a given time
Color Constancy
Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object
Opponent-process theory
Opposing retinal processes enable color vision–> explains after images
Young-Helmholtz trichromatic theory
The retina contains 3 different color receptors (red, green, blue). When stimulated in a combination, they can produce the perception of any color
