Lecture 5: Perception Mechanisms Flashcards
receive stimuli outside of our bodies
exteroceptive sensory systems
Process of detecting the presence of stimuli
sensation
Higher-order process of integrating, recognizing, and interpreting patterns of sensations
perception
types of sensory areas of cortex
- primary sensory cortex
- secondary sensory cortex
- association cortex
Areas that receive most of their input from the (1) primary sensory cortex or (2) other areas of secondary sensory cortex (in same system)
secondary sensory cortex
Area that receives most of its input directly from the the thalamic relay nuclei
primary sensory cortex
Any area that receives its input from more than one sensory system
association cortex
most input in the association cortex comes via areas of __________
secondary sensory cortex
Characterizes the interactions among the three types of sensory cortex and among other sensory structures
three major principles
three major principles
- hierarchical organization
- functional segregation
- parallel processing
“Sensory structures are organized based on the specificity and complexity of their function”
hierarchical organization
“Each of the 3 cortex levels in a sensory system contain functionally distinct areas that specialize in different kinds of analysis”
functional segregation
“information flows through the components over multiple pathways”
parallel system
“simultaneous analysis of a signal in different ways by multiple parallel pathways of a neural network”
parallel processing
Vibrations of air molecules (that stimulate the auditory system)
sounds
human hearing capacity
20 - 20,000 hertz
amplitude =
loudness
frequency =
pitch
complexity =
timbre
A sound of one single frequency
pure tone
pure tone exists only in
- laboratories
- sound recording studios
related to fundamental frequency
pitch
Mathematical procedure for breaking down complex waves into their component sine waves
fourier analysis
Transmit sound vibrations from the external ear to the middle ear (particularly the ossicles)
tympanic membrane (eardrum)
3 small bones; Connected to each other and send the sound vibrations (which they amplify) to the inner ear (particularly the cochlea)
ossicles
3 small bones
- malleus
- incus
- stapes
the hammer
malleus
the stirrup
stapes
the anvil
incus
junction point between the middle ear and the inner ear
oval window
long, coiled tube with an internal structure (Organ of Corti) running almost to its tip
cochlea
cochlea is filled with ____ that ripples due to the vibrations
fluid
‘different hair cells respond to different frequencies of sound’
tonotopic
bundles of stereocilia move along the waves created by the rippling (due to vibration)
organ of corti
organ of corti convert wave movements into ____ signals which will travel along the auditory nerve
electrical signals
elastic membrane in cochlear wall
round window
current network of auditory pathways
axons of auditory nerves - medial geniculate nuclei - primary auditory complex
signals are transmitted to both ____ and _____
- ipsilateral
- contralateral
inherently complex in auditory system
subcortical pathways
Receives the majority of its input from medial geniculate nucleus
primary auditory complex
primary auditory complex is located in the ______
temporal lobe
areas of auditory cortex
- 13 separate areas
- core region
- belt
- parabelt areas
band of areas of secondary auditory cortex
belt
areas of secondary auditory cortex outside the belt
parabelt areas
collection of 3 adjacent areas in primary auditory cortex
core region
principles of organization
- organized in functional columns
- tonotopic
- periodotopy
vertically, auditory neurons tend to respond optimally to sounds in the same frequency range
organized in functional columns
organized acc. to temporal components of sound
periodotopy
periodotopy refers to the changes in ____ of sounds in our environment over a period of time
intensity
2 main cortical streams of auditory analysis
- anterior auditory pathway
- posterior auditory pathway
ultimately conducted to the prefrontal cortex and posterior parietal cortex
auditory signals
More involved in identifying sounds (what)
anterior auditory pathway
More involved in locating sounds (where)
posterior auditory pathway
have traditionally been assumed to interact in the association cortex
sensory system
areas of cortex where SS interactions (associations) take place
association cortex
Widely used to investigate SS interactions
functional brain imaging
effects of damage to the auditory system
- auditory cortex damage
- deafness
Major permanent loss of ability to process structural aspects of sounds
auditory cortex damage
- One of most prevalent human disabilities
- Can lead to feelings of social isolation
deafness
______ is rare (only 1%)
total deafness
2 common classes of deafness
- conductive deafness
- nerve deafness
damage to ossicles
conductive deafness
Damage to cochlea or auditory nerve
nerve deafness
major cause of nerve deafness
loss of hair cell receptors