Lecture 4 + Ch6 Module 18-20 Flashcards
Define Prosopagnosia
face blindness, inability to recognize faces
Define Sensation
Receiving, translating, and transmitting raw sensory information from the external and internal environments to the brain
Define Sensory Receptors
sensory nerve endings that respond to stimuli
Define Perception
Our brain organizes and interprets sensory info, enabling us to recognize objects and events as meaningful
Define Bottom-up Processing
info processing that begins with the sensory receptors and works up to the brain’s integration of sensory information
Define Top-down Processing
Interpreting what our senses detect
What are the 3 steps of the sensation process?
- Reception
- Transduction
- Transmission
Define Reception
the stimulation of sensory receptor cells by energy
Define Transduction
transforming cell stimulation into neural impulses
Define Transmission
Delivering neural info to the brain to be processed
Define Psychophysics
the study of relationships between the physical characteristics of stimuli and our psychological experience of them
Define Absolute Threshold
the minimum stimulus energy needed to detect a particular stimulus half the time
Define Subliminal
Anything below Absolute Threshold
Define Sensory Reduction
Filter and analyze incoming sensations before sending neural impulses onto the brain
Define Signal Detection Theory
a theory predicting how and when we detect the presence of a faint signal amid background noise
Define The Difference Threshold
the minimum difference between two stimuli required for detection half the time. “Just noticeable difference”
Define Sensory Adaptation
diminished sensitivity as a consequence of constant stimulation
Why don’t we visually notice sensory adaption?
Our eyes are always moving, causing the stimulation on the eyes’ receptors to continually change
Define Perceptual Set
a mental predisposition to perceive one thing and not another
What is Context?
Affects our interpretations, our expectations influence our perceptions constantly
What is Motivation?
Motives give us energy as we work toward a goal
What is Emotion?
It can shove our perceptions in one direction or another
How does light travel?
in waves, and the shape of those waves influence what we see
Define Wavelength
The distance from one peak of one light or sound wave to the peak of the next
Light wave’s amplitude determines…
the intensity – the amount of energy the wave contains
Short light wavelength =
high frequency (bluish colours)
Long light wavelength =
low frequency (reddish colours)
Great light amplitude =
bright colours
Small light amplitude =
dull colours
How does light enter our eye?
through the cornea, which bends light to help provide focus
Define Iris
a coloured muscle that dilates or constricts in response to light intensity
Define Rods
Retinal receptors that detect black, white, and gray, and are sensitive to movement
Why are Rods necessary?
For peripheral and twilight vision when cones don’t respond
Define Cones
retinal receptors that are concentrated near the center of the retina, and function in well-lit conditions
Why are Cones necessary?
they detect fine detail and give rise to colour sensations
Are there more rods or cones in our eye?
Rods (20 times more common than cones)
What are the 2 stages of colour processing?
- Trichromatic Theory
- Opponent-Process Theory
What is Trichromatic Theory?
The retina’s red, green, and blue-sensitive cones respond in varying degrees to different colour stimuli
What is Opponent-Process Theory?
within one colour pair, one will respond positively to one colour and negatively to the other
Define Parallel Processing
processing multiple aspects of a stimulus or problem simultaneously
Define Feature Detectors
nerve cells in the brain’s visual cortex that respond to specific features of the stimulus
Amplitude of sound waves determines…
their perceived loudness
short sound waves =
high frequency and high pitch
long sound waves =
low frequency and low pitch
great sound amplitude =
loud sounds
small sound amplitude =
soft sounds
What is the absolute threshold for hearing?
zero decibels
What does the outer ear do?
collects the sound and funnels it to the eardrum
What does the middle ear do?
a piston made of three tiny bones – the hammer, anvil, and stirrup – picks up the vibrations and transmits them to the cochlea
What does the inner ear do?
moves waves of fluid from the oval window over the cochlea’s “hair” receptor cells which send signals through the auditory nerves to the temporal lobe of the brain
Define Sensorineural Hearing Loss
the most common form of hearing loss, caused by damage to the cochlea’s receptor cells or to the auditory nerve (nerve deafness)
Conduction Hearing Loss
a less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea
Define Place Theory
we hear different pitches because different sound waves trigger activity at different places along the cochlea’s basilar membrane
Define Frequency Theory
the brain reads pitch by monitoring the frequency of neural impulses traveling up the auditory nerve
What is the problem with frequency theory?
An individual neuron cannot fire faster than 1000 times per second, so what about sounds with frequencies above 1000 waves per second?
Define Volley Principle
Neural cells can alternate firing, so by firing in rapid succession, they can achieve a combine frequency above 1000 waves per second (the solution to frequency theory problem)
Which theory best explains how we sense low pitches?
Frequency Theory + Volley Principle
Which theory best explains how we can sense high pitches?
Place Theory
What are the 3 basic perceptual processes?
- Selection
- Organization
- Interpretation
Define Selection
attending to some sensory stimuli while
ignoring others
Define Organization
assembling information into patterns
that help us understand the world
Define Interpretation
how the brain explains sensations
We organize sensory information in terms of:
form
depth
motion
constancy
colour
Define Depth Perception
Depth perception involves both binocular (two eyes) and monocular (one eye) cues
What are Binocular Depth Cues?
retinal disparity (different images fall on each retina due to the distance between our eyes) & convergence (The closer the object, the more our eyes are turned inward)
Define Perceptual Illusions
False or misleading perceptions that help
scientists study normal processes of perception
What are the 4 major factors of interpretation?
- Perceptual Adaptation
- Perceptual Set
- Context effects
- bottom up vs top down processing
What are our chemical senses?
Taste and Smell
Define Anosmia
unable to smell
What are the 5 taste’s sensations?
sweet, salty, sour, bitter, and umami (MSG)
We smell something when…
molecules of a substance carried in the air reach a tiny cluster of receptor cells at the top of each nasal cavity
Pain is the body’s way of saying…
something has gone wrong
Pain is a…
biopsychosocial phenomenon
What is Gate-Control Theory?
the spinal cord contains a neurological “gate” that controls the transmission of pain messages to the brain
How can chronic pain be treated?
gate-closing stimulation and mental activity
What are the 3 ways to control pain?
- placebo
- distraction
- hypnosis
What are the four sensations of touch?
- pressure
- warmth
- cold
- pain
What is Kinesthesia?
keeps you aware of your body parts’ position and movement
What is Vestibular Sense?
monitors your head’s position and movement
