Focused Questions Section 2 Flashcards
Based on textbook and lecture
What are the three levels of the sensory cortex?
primary sensory cortex
secondary sensory cortex
association cortex
The primary sensory cortex receives input mostly from
thalamic relay nuclei
The secondary sensory cortex receives input mostly from
the primary cortex or other secondary sensory cortex areas of the same system
The association cortex receives input from
more than one sensory system
How do we characterize the interaction between each level of the sensory cortex?
hierarchical organization, functional segregation, and parallel processing
What is hierarchical organization?
organization based on the specificity and complexity of function
What is functional segregation?
each of the three levels of the cerebral cortex in each sensory system contains functionally distinct areas for different types of analysis
What is parallel processing?
the simultaneous analysis of a signal in different ways
Sensory systems can be considered ___ systems
parallel
Which system is responsible for the perception of sound?
the auditory system
List the physical dimensions of sound and their correspondent perceptual dimension
amplitude –> loudness
frequency –> pitch
complexity –> timbre
The combination of the individual dimensions of sound results in
the formation of a complex sound wave
In what order are sound waves/vibrations passed through the mechanisms of the ear? (8)
auditory canal - tympanic membrane - ossicles (stapes) - oval window - cochlea fluid - organ of Corti - hair cells - auditory nerve
Similar to the somatotopic organization of the somatosensory system, the auditory system can be described as _______
tonotopic
Neurons in both the auditory cortex and the cochlea are ________
cochlea; frequency specific
What area is recognized for its responsibility in multisensory integration?
posterior parietal
The vestibular system explains balance in a way that it processes
info about the direction and intensity of head movements
What is the order of processing sound from the ear to the primary auditory cortex?
axons of olivary neurons - inferior colliculi - medial geniculate nuclei of thalamus - primary auditory cortex
What system is responsible for the localization of sound in space?
the subcortical auditory system
In what ways do the lateral and medial superior olives differ in the way they allow you to localize sound?
the lateral olives detect differences in the amplitude of sound from two ears; the medial superior olives detect differences in times of arrival
What is the location of the primary auditory cortex?
the temporal lobe
Describe the organization of the auditory cortex
the primary auditory cortex is organized in functional columns and organized tonotopically
Each area of primary and secondary auditory cortex appears to be organized on the basis of ___
frequency
What are the two main cortical streams of auditory analysis and what is the difference between the two?
the anterior auditory pathway is more involved in identifying sounds (what); the posterior auditory pathway is more involved in locating sounds (where)
The primary auditory cortex is located within the superior _____ gyrus and is thought to be essential for _______
Temporal; detection of temporal patterns of sound
Severe hearing problems typically result from damage to which parts of the ear
the inner ear, the middle ear, or the nerves leading from them
If only part of the cochlea is damaged an individual may experience
nerve deafness for some frequencies but not others
What three subsystems compose the somatosensory system?
exteroceptive - senses stimuli applied to the skin
proprioceptive - monitors position of the body
interoceptive - conditions within the body
What are free nerve endings?
they are the simplest cutaneous receptors that are sensitive to temperature changes and pain
What are Pacinian corpuscles and what do they do?
they are the largest and deepest cutaneous receptors; they adapt rapidly and react to only sudden displacements of the skin
What is the difference between Merkel’s and Ruffini receptors?
they are both slow adapting; Merkel’s receptors respond to gradual skin indentation while Ruffini respond to skin stretch
A person with the inability to recognize and discriminate objects by touch would be said to have
asterognosis
What is the main difference in functioning of the two major somatosensory pathways?
the dorsal-column medial-lemniscus handles touch and proprioception; the anterolateral system handles pain and temperature
The organization of the somatosensory system can be best described as
somatotopic - organized according to a map of the body
What is the main result of damage to the primary somatosensory cortex?
typically mild disability in detecting light touch and reduced ability to identify objects by touch
The minimal impairment in functioning following damage to the S1 cortex is explained by
the numerous parallel pathways in the somatosensory system
What is asomatognosia and what causes it?
the inability to recognize parts of one’s own body; typically on the left side as a result of damage in the right temporal and posterior parietal lobe
How can we explain the Rubber-Hand Illusion?
(not 100% sure) thought to be due to the roles of the association cortex in the posterior parietal and frontal lobes as well as the bimodal neurons (visual + somatosensory)
What three aspects of pain explain the paradox of pain perception?
the adaptiveness of pain
lack of clear cortical representation
descending (down-regulation) pain control
Which areas do we typically see activated with the introduction of painful stimuli?
thamalus, S1, S2, insula, and anterior cingulate
The anterior cingulate is not responsible for the perception of pain itself, however, is typically associated with
expectation of pain, emotional reaction, and adaptive response to minimize pain
Which brain areas are associated with the effective suppression of pain through cognitive and emotional factors?
the periaqueductal gray (PAG) - produce analgesic (pain blocking) effect
endogenous opioids (endorphins)
What underlies the phenomenon of Phantom Limb Pain?
best explained by neuropathic pain - severe, chronic pain in the absence of recognizable pain stimulus; the mechanism is unknown
