Lecture 9: Hearing, Somatosenses (Tactile Perception, Proprioception & Pain) Chemosense (Taste & Smell) Flashcards
What is Audiology?
Hearing, testing, and optimization of acoustic stimulus using hearing aids
What is Otolaryngology?
A specialization in conductive and sensorineural hearing losses, cochlear implants
What is Speech Therapy?
Specialization in developmental aspects of hearing difficulties affecting speech
4 ways in which Hearing Loss Affects Children?
- Can delay the development of speech-related receptive and expressive communication problems
- Speech related language deficits can cause learning problems that result in reduced academic achievement
- Can lead to social isolation and poor self regard
- Impacts vocational choices
What are Outer Hair Cells?
Mechanical amplifiers that involve prestin “ a motor protein” that performs a direct voltage-to-displacement function that mechanically enhances the vibrations of the basilar membrane caused by acoustic stimulation
What are Inner Hair Cells?
Acoustic transducers effected by shearing
What happens when a hair cell depolarizes?
Voltage gated calcium channels at the base of the cell open, and the resulting influx of calcium causes synaptic vesicles to fuse to the cell membrane and release a neurotransmitter into the synaptic cleft between the hair cell and the cochlear nerve fibers.
What is Auditory-Evoked Potentials (AEPs)?
Electrical responses from different generators within the auditory system (electrical signal is very small)
What is the difference between longer latency and shorter latency in AEPs?
Shorter Latency: Components reflect peripheral visual processes - auditory nerve, cochlear nucleus, superior olive, and inferior colliculus of the brainstem
Longer Latency: Components reflect central processes (medial geniculate nucleus of the thalamus, A1, A2, and higher cortical areas
What is Conductive Hearing Loss?
Factors affecting the conduction of sound to the cochlea (serious otitis media)
What is Sensorineural Hearing Loss and what is it caused by?
Factors affecting transduction of acoustic energy to neural response in the cochlea
Caused By Potentially:
- Diseases (e.g mumps, measles)
- Ototoxic drugs (e.g quinine, solvents)
- Trauma
- Aging
- Etc…
What is Central Auditory Processing Disorder?
Problems with auditory localization (binaural fusion), auditory discrimination, pattern recognition, temporal ordering, temporal masking, etc…
What is Equilibrioception?
The capacity to sense the position of various parts of the body and use that information as feedback in motor control processes that dynamically modify the position of body parts to maintain posture and antigravity stance
Balance is generated and maintained in the Vestibular System!!
What are 3 Fluid-filled semicircular canals attached to each cochlea code rotational acceleration of the head?
- Anterior SCC
- Posterios SCC
- Lateral SCC
What is Anterior SCC?
Codes for nodding movements of the head, called “pitch”
What is Posterior SCC?
Codes for tilting yu head towards your shoulder, called “roll”
What is Lateral SCC?
Codes for head movements while looking from side to side, called “yaw”
What are the 2 Otolith Organs?
Utricle and Saccule
What are the 2 Otolith Organs most Sensitive to?
Utricle: Mosts sensitive to upright head tilt
Saccule: Most sensitive to horizontal head tilt
What are SA1 Mechanoreceptors?
Slowly adapting, small receptive fields and produce a sustained response to stimulation - Merkel Corpuscle end organ (mediate the perception of form and roughness)
What are SA2 Mechanoreceptors?
Slowly adapting, large receptive fields - Ruffini Corpuscle end organ (pressure, skin stretch)
What are RA1 Mechanoreceptors?
Rapidly adapting, small receptive fields, produce a transient response to stimulation - Meissner’s Corpuscles end organ (light touch, changes in texture, slow vibrations)
What are RA2 Mechanoreceptors?
Rapidly adapting, large receptive fields, produce transient response to stimulation - Pacinian Corpuscles (deep pressure, fast vibrations)
What are Thermoreceptors?
Free nerve endings in the dermis - detect heat and cold in the innocuous temperature range
