learning outcomes pt. 1

Sagittal Plane - Alternative Name

Median plane

Transverse Plane - Alternative Name

Axial plane

Coronal Plane - Alternative Name

Frontal plane

Pitch - Plane of Rotation

Median (sagittal) plane

Pitch - Associated Gesture

"Yes" head nods

Pitch - Axis of Rotation

y-axis

Yaw - Plane of Rotation

Transverse (axial) plane

Yaw - Associated Gesture

"No" head nods

Yaw - Axis of Rotation

z-axis

Roll - Plane of Rotation

Frontal (coronal) plane

Roll - Associated Gesture

"Comme ci, comme ça" side-to-side head tilts

Roll - Axis of Rotation

x-axis

X-Axis Translation - Direction

Backward and forward linear motion

Y-Axis Translation - Direction

Sideways linear motion

Z-Axis Translation - Direction

Up and down linear motion

Pitch Tilt - Direction

Forward or backward tilt relative to gravity

Roll Tilt - Direction

Left or right tilt relative to gravity

Yaw Tilt - Upright Absence

Yaw rotation when upright is aligned with gravity, producing no gravitational tilt change

Semicircular Canals - Quantity

3 per inner ear (anterior, posterior, horizontal)

Otolith Organs - Quantity

2 per inner ear (utricle, saccule)

Semicircular Canals - Effective Stimulus

Angular (rotary) acceleration

Otolith Organs - Acceleration Stimulus

Linear acceleration

Otolith Organs - Position Stimulus

Head tilt with respect to gravity

Crista - Location

Inside the ampulla of each semicircular canal

Cupula - Structural Role

Gelatinous structure in ampulla embedding stereocilia of crista hair cells

Crista - Hair Cell Count

Approximately 7,000 hair cells per crista

Crista Hair Cells - Kinocilium Alignment

All kinocilia in a given crista are arranged on the exact same side

Hair Cell Depolarization - Deflection Direction

Bending stereocilia toward the kinocilium and tallest stereocilia

Hair Cell Hyperpolarization - Deflection Direction

Bending stereocilia away from the kinocilium

Hair Cells - Axon Presence

Hair cells do not have axons and do not generate action potentials

Hair Cell Depolarization - Neurotransmitter

Increased release of glutamate at afferent synapse

Hair Cell Depolarization - Firing Response

Increased action potential firing rate in vestibular nerve fibers

Hair Cell Hyperpolarization - Firing Response

Decreased action potential firing rate in vestibular nerve fibers below spontaneous rate

Horizontal Canal - Sensitivity Axis

Maximally sensitive to yaw head rotations around a vertical perpendicular axis

Horizontal Canals - Push-Pull Pairing

Right horizontal canal paired with left horizontal canal

Right Yaw Turn - Right Canal Response

Depolarization of hair cells and increased firing rate in right vestibular nerve

Right Yaw Turn - Left Canal Response

Hyperpolarization of hair cells and decreased firing rate in left vestibular nerve

Left Anterior Canal - Push-Pull Partner

Right posterior canal

Right Anterior Canal - Push-Pull Partner

Left posterior canal

Semicircular Canals - Amplitude Coding

Coded by magnitude of change in firing rate relative to spontaneous baseline

Utricle Macula - Hair Cell Count

Approximately 30,000 hair cells

Utricle Macula - Spatial Orientation

Horizontal plane orientation

Saccule Macula - Hair Cell Count

Approximately 16,000 hair cells

Saccule Macula - Spatial Orientation

Vertical plane orientation

Utricle Kinocilia - Striola Orientation

Kinocilia are oriented toward the striola

Saccule Kinocilia - Striola Orientation

Kinocilia are oriented away from the striola

Otolith Membrane - Calcium Crystals

Otoconia

Otoconia - Chemical Composition

Calcium carbonate

Utricle - Acceleration Sensitivity

x-axis and y-axis linear acceleration

Utricle - Tilt Sensitivity

Pitch tilt and roll tilt

Saccule - Acceleration Sensitivity

x-axis and z-axis linear acceleration

Saccule - Tilt Sensitivity

Pitch tilt

Otolith Organs - Push-Pull Response

Movement exciting hair cells on one side of striola maximally inhibits hair cells on opposite side

Otolith Organs - Amplitude Coding

Coded by higher firing rate in vestibular nerve fibers for larger displacements/movements

Constant Rotation (15s) - Cupula State

Cupula returns to its resting position

Constant Rotation (15s) - Firing Rate

Vestibular nerve firing rate returns to spontaneous level

Sudden Rotational Stop - Cupula Movement

Cupula deflects in the opposite direction of original motion

Sudden Rotational Stop - Firing Response

Transient decrease in nerve firing rate below baseline

Alcohol Ingestion - Endolymph Effect

Changes density of endolymph relative to cupula, causing cupula deflection

Alcohol Ingestion - Vestibular Phenomenon

Alcohol-induced head spinning (positional alcohol nystagmus)

Oculogyral Illusion - Physical Cause

Reverse cupula deflection following rapid body stopping before returning to rest

Oculogyral Illusion - Perceptual Effect

Visual disorientation and apparent movement of stationary targets after spinning

Oculogravic Illusion - Physical Cause

Inability of macula to distinguish horizontal linear acceleration from static head tilt

Oculogravic Illusion - Perceptual Effect

Apparent backward tilt and visual elevation experienced during forward body acceleration

Vestibulo-Cochlear Nerve - Cranial Number

Cranial Nerve VIII

Merkel Cell - Abbreviation

SA I (Slowly Adapting Type I)

Merkel Cell - Skin Location

Superficial skin layers (epidermis)

Merkel Cell - Receptive Field

Small receptive field

Merkel Cell - Adaptation Rate

Slow adaptation rate

Merkel Cell - Maximum Sensitivity

Sustained pressure, very low frequency (< ~5 Hz)

Merkel Cell - Perceptual Function

Perception of coarse texture and pattern

Meissner Corpuscle - Abbreviation

FA I (Fast Adapting Type I)

Meissner Corpuscle - Skin Location

Superficial skin layers (dermal papillae)

Meissner Corpuscle - Receptive Field

Small receptive field

Meissner Corpuscle - Adaptation Rate

Fast adaptation rate

Meissner Corpuscle - Maximum Sensitivity

Temporal skin deformation (~5–50 Hz) and skin slip

Meissner Corpuscle - Perceptual Function

Low-frequency vibration and grasp stability

Ruffini Ending - Abbreviation

SA II (Slowly Adapting Type II)

Ruffini Ending - Skin Location

Deep skin layers (dermis)

Ruffini Ending - Receptive Field

Large receptive field

Ruffini Ending - Adaptation Rate

Slow adaptation rate

Ruffini Ending - Maximum Sensitivity

Sustained downward pressure and lateral skin stretch (~5–50 Hz)

Ruffini Ending - Perceptual Function

Perception of finger position and skin stretch

Pacinian Corpuscle - Abbreviation

FA II (Fast Adapting Type II)

Pacinian Corpuscle - Skin Location

Deep skin and subcutaneous tissue

Pacinian Corpuscle - Receptive Field

Large receptive field

Pacinian Corpuscle - Adaptation Rate

Fast adaptation rate

Pacinian Corpuscle - Maximum Sensitivity

High-frequency temporal changes in skin deformation (~50–700 Hz)

Pacinian Corpuscle - Perceptual Function

High-frequency vibration and fine texture perception

Glabrous Skin - Definition

Hairless skin found on palms of hands and soles of feet

DCML Pathway - Primary Modalities

Touch pressure, vibration, joint, and position sense (proprioception)

DCML Pathway - Peripheral Fiber

A-beta fibers

Spinothalamic Pathway - Primary Modalities

Temperature and pain

Spinothalamic Pathway - Peripheral Fibers

A-delta and C fibers

DCML Pathway - First Synapse

Gracile or cuneate nucleus in ipsilateral medulla

Spinothalamic Pathway - First Synapse

Substantia gelatinosa (layer II) in dorsal horn of spinal cord

DCML Pathway - Second Synapse

Ventral posterolateral (VPL) nucleus of contralateral thalamus

Spinothalamic Pathway - Second Synapse

Ventral posterolateral (VPL) nucleus of contralateral thalamus

DCML Pathway - Third Synapse

Primary somatosensory cortex (S1) in parietal lobe

Spinothalamic Pathway - Third Synapse

Primary somatosensory cortex (S1) in parietal lobe