Sensation
the process by which a stimulated receptor(sense organs) creates a pattern of neural messages that represent stimulus in the brain.
Sensation
stimulus
Perception
a process that makes sensory patterns meaningful
Perception
how we interpret the stimulus
Transduction
changing stimulus into nerve signals. converts physical energy into nerve signals
Sensory Adaptation
diminishing responsiveness of sensory systems to prolonged simulation
Sensory adaptation example
getting used to cold water when swimming
Absolute Threshold
the amount of stimulation needed for signal detection
Difference threshold
the smallest physical difference between stimuli that can be recognized as difference
Just Noticeable Difference(JND)
difference threshold
Weber's Law
the JND is large when stimulus intensity is high and the JND is small when intensity is low.
Weber's Law Example
its easier to tell the difference in tv volume between 4 and 5 and harder to tell the difference between 110-115
Fechner's Law
small stimulus is perceived relatively accurate. Larger stimulus is harder.
Steven's Power Law
Fechner's Law
Signal Detection Theory
sensation depends on characteristics of the stimulus, background stimulus, and the detector. detects realtionships among stimulus. we decide what we detect
Retina
thin, light sensitive layer at the back of the eyeball. contains photoreceptors and nerve cells.
Photoreceptors
light sensitive cells (neurons) in the retina that convert light energy to neural impulses.
Rods
Photorepceptors sensitive to dim light not colors
Cones
Photoreceptors sensitive to colors not dim light
Fovea
area of sharpest vision in our eye
Optic Nerve
bundle of neurons that carries visual information from the retina to the brain
Blindspot
caused by optic nerve. there are no photoreceptors on the optic nerve. stimulus here cannot be seen
Visual Cortex
part of the brain that processes what we see
Brightness
a psychological sensation cause by intensity of light waves
Color
hue. psychological sensation derived from the wavelength of visible life. Color is not a property of the external world.
Electromagnetic Spectrum
the entire range of electromagnetic energy (x rays, microwaves, and visible light)
Visible Spectrum
the small part of the electromagnetic spectrum to which our eyes are sensitive. creatures can have difference visible spectrums
Trichromatic Theory
the idea that colors are sensed by three different cones sensitive to light in the red, blue, and green wavelengths.
Opponent Process Theory
the idea that cells in the visual process colors in complimentary pairs. Explains color sensation from the bipolar cells onward the visual system.
Afterimages
sensations that linger after the stimulus is removed
Colorblindness
total inability to distinguish colors
Frequency
number of cycles completed by a wave in a given amount of time. determines pitch
Amplitude
physical stregth of a wave. determines volume
Sound becomes Sensations
1. Tympanic membrane 2. cochlea 3. Basilar Membrane 4. Auditory nerve and Auditory Cortex
Tympanic Membrane
ear drum.
Cochlea
primary hearing organ. coiled tube. Transduction takes place here.
Basilar Membrane
In cochlea. A thin strip of tissue sensitive to vibrations. contains hair cells. tranduction
Auditory Nerve
neural pathway connecting ear to brain
auditory cortex
in temporal lobe. processes sound and adds perception
Pitch
high or low. characterized by frequency
Place theory
different places in the Basilar membrane detect different levels of pitch
Frequency Theory
we are designed to hear frequencies above 1000 and below 5000 hertz
Loudness
volume. characterized by amplitude
Timbre
quality of the sound wave derived from wave complexity
Conduction Deafness
inability to hear based on damage to ear structures
Nerve Deafness
an inability to hear based on problem with the body's ability to transmit impulses from the cochlea to the brain. usually problems with the auditory nerve.
Vestibular Sense
sense of body orientation with respect to gravity. allows us to sense body movement and maintain balance
Kinesthetic Sense
muscle memory sense. sense of body position and movement of body parts relative to each other
Olfaction
sense of smell
Olfactory Bulbs
brain site of olfactory processing. below frontal lobe. may have developed laet. does not go through the thalamus
Pheromones
chemical signals released by organisms to communicate with other members of the species. they say things like "Stay away" "Come here" "My Property
Gustation
sense of taste
Skin Senses
sensory systems for processing touch, warmth, pressure, warmth, cold, pain, and texture
Gate-Control Theory
we have a neural gate that can block incoming pain signals
Placebo
substances that appear to be drugs but are not. used in deception
Placebo Affect
a response to a placebo caused by the belief that the subject is taking real drugs.
Percept
meaningful product of a perception
Feature Detectors
cells in the cortex that specialize in extracting certain feautures of a stimulus
Binding Problem
an unsolved mystery concerning the processes used by the brain to form a single perception from many stimuli
Bottom-up Processing
analysis emphasizing characteristics of the stimulus rather than internal conceptions. stimulus then perceives
Top-Down Processing
anaylsis that emphasizes the perceiver's expectaions, concept memories, and other cognitive factors. looks at perception then the atual stimulus
Perceptual Constancy
ability to recgonize the same object under different conditions.
Illusion
incorrect perception of a stimulus. shared by others of the same perceptual environment.
Ambiguous Figures
images that are capable of more than one interpretation
Gestalt Psychlogy
much of perception is built by innate processing in the brain
Figure
the part of a pattern that stands out
Ground
the part ofan image that blends in. the background
Closure
identifies the tendency to fill gaps to see incomplete figures as complete.
Laws of Perceptual Grouping
laws that suggest how our brains prefer to group elements together to form a perception
Law of Similarities
we group similar objects together to form a perception
Law of Proximity
we group objects that are near each other
Law of Continuity
we prefer perceptions of continuous connected figures
Law of Common Fate
we group stimuli together that share a common motion or destination. example- a school of fish or students in the hallway
Law of Pragnanz
minimum principle of perception.
Binocular Cues
information taken in by both eyes that aids in depth perception
Retinal Desparity
difference in perspectives of two eyes
Convergence
lines of vision from each eye converge at different angles on objects at different distances
Monocular cues
information about depth that relies on one eye
Relative Size
we use the size of the object to determine distance (or vice versa)
Light and Shadow
we tend to perceive objects that reflect the most light as closer
Interposition
when one object blocks another we perceive it as closer
Relative Motion
things closer to us seem to move faster
Relative Clarity
Atomospheric Perception. haze or fog covered objects seem farther away.the less fog the closer we perceive it
Relative Height
the taller something is we perceive it to be farther away
Linear Perspective
parallel lines seem to converge with distance
Learning Based Inference
resulted perception from learning
Context and Expectations
a theory that states we struggle to recognize objects when we don't expect to see them.
Perceptual Set
readiness to detect a particular stimulus