Threshold: Dividing points
between energy levels that
do and do not have a
detectable effect
JDN: smallest difference in
the amount of stimulation
that a specific sense can
detecct
Weber's law: size of noticeable
difference is a constant
proportion of size of the initial
stimulus
Signal Detection theory:
detection of stimuli involves
decision processes as well as
sensory process, which are
both influenced by a variety of
factors besides stimulus
intensity
Perception without Awareness:
Subliminal perception- sensory input
without conscious awareness
Sensory adaptation: gradual
decline in sensitivity due to
prolonged stimulation
Our sense of Sight: The Visual System
Stimulus: light- is a form
of electromagnetic
radiation that travels as
a wave, moving enough
at the speed of light
The Eye: creates an image
of the visual world
Lens: transparent eye structure that
focuses the light rays falling on the
retina.
Farsighted and nearsighted
Pupil: helps regulate the amount of light
passing into the rear chamber of the eye
The retina: absorbs light, process images,
sends visual information to the brain
Visual receptors: rods and cones
Dark and light adaptation
Information processing in the retina
Vision and the Brain
Visual pathways to the
brain- Optic chiasm-
optic nerves from the
inside half of each eye
cross over and then
project to the opposite
half of the brain
Information processing in the visual cortex
Viewing the world in Colour
The stimulus for colour: subtractive colour mixing and additive mixing
Trichromatic Theory of Colour Vision-
the three different type of receptors
with different sensitives to different
light wavelengths
Opponent Process theory of
colour vision
Complementary colours and afterimage
The Visual system: Perceptual Processes
Perceiving forms, patterns, and objects
Reversible figure- drawing that is compatible
with two interpretations that can shift back
and forth
Perceptual set- Readiness to perceive a stimulus in a particular way
Figure and ground, Proximity, closure, similarity, simplicity, and Continuity
Formulating Perceptual Hypotheses
Perceiving Depth and Distance
Depth perception: involves interpretation of visual cues that indicate
how near or far away objects
Binocular Cues: clues about the distance
based on the differing views of the two eyes
Monocular Cues: clues about distance
based on the image in wither eyes alone
Perceptual Constancies In Vision
Perceptual constancy: tendency to experience a stable perception in the face of continually changing
sensory input
The Power of Misleading Cues: Optical Illusions
Optical Illusions: inexplicable discrepancy between he appearance of
visual stimulus and its physical reality
Different illusions- Muller-Lyer illusion, The ames room, A monster illusion
Our sense of Hearing: The auditory system
The Stimulus: Sound
sounds waves are vibrations of molecules, which means that they must travel through some physical medium, such as air
Hearing Capacities
Wavelengths of sound are described in terms of
their frequency which are then measured in
cycles per second
Sensory Processing in the ear
Ears channel energy to the
neural tissue that receives it
Different parts of the ear: External ear- Pinna, Middle ear-
three tiny bones (Hammer, anvil, strirrup, inner ear- cochlea,
basilar
Auditory perception: theories of hearing
Place theory: holds that perception of pitch corresponds to the vibration of different portions, or places, along the basilar membrane
Frequency theory: holds that perception of pitch corresponds to the rate, or frequency, at which the entire basilar membrane vibrates
Our Chemical senses: Taste and smell
Taste: the gustatory system
Gustatory system: the sensory system for taste
Smell-The Olfactory system
Pheromones are chemical messages. they can be sent by
one organism and recieved by another member of the
same species
Sense of touch: Sensory systems in the skin
Feeling pain
Pathways to the Brain
Two path ways slow and fast.
Puzzles in Pain perception
Pain can be influenced by personality, mood
and other factors. its is not automatic.
Gate-controlled theory: holds that incoming pain signals can be blocked in the spinal cord. endorphins and a descending neural pathway appear to be responsible for the suppression of pain by the central nervous system.
Our other senses
Kinesthetic system: the positions of the various parts of the body
The Vestibular system
responds to gravity and keeps you informed of your body's location in space