Week 4&5: Sensation & Perception Flashcards
Our internal perception is a _____________ of the external world
construction
detection of physical energy and
transduction, the conversion into
neural signals
Sensation
interpretation of sensations
by the brain
Perception
What are the steps of sensation to perception?
- Stimulus energy (light, sound, smell, etc)
- Sensory receptors (eyes, ears, nose, etc.)
- Neural impulses
- Brain (visual, auditory, olfactory areas)
What is the sense receptor for hearing?
Hearing receptor
Transduction of hearing
uses mechanoreception: detection of vibration, perceived as hearing
sense organ for hearing
Ears
What is the sense receptor for touch?
mechanoreceptors
Transduction of Touch
uses mechanoreception: detection of pressure, temperature, stretching, vibration, perceived as touch.
sense organ for touch
skin
What is the sense receptor for smell?
olfactory receptor cells
Transduction of Smell
uses chemoreception: detection of chemical stimuli, perceived as smell
sense organ of smell
nose
What is the sense receptor for taste?
Taste receptor cells
Transduction of Taste
Uses chemoreception: detection of chemical stimuli, perceived as taste.
sense organ for taste
tongue
What is the sense receptor for vision?
photoreceptors (cones and rods)
Transduction of vision
Uses photoreception: detection of light, perceived as sight
sense organ for vision
eyes
Amplitude (intensity)
Loudness
Frequency
Pitch
Complex sounds
Timbre
Physical dimensions of sound
amplitude, frequency, complex sounds
Perceptual dimension of sound
loudness, pitch, timbre
What’s the difference in waveforms between loud and soft amplitudes?
taller waves for loud, shorter waves for softer
What’s the difference in waveforms between low and high frequency?
Low = longer wavelength (more spread out)
high = shorter wavelength (more close together)
Ears detect sound as _____________________ caused by a sound wave
variations in air pressure
Humans can hear frequencies from ______________.
20Hz to 20kHz
contours explain how
sounds at different frequencies can
seem equally loud.
Equal - loudness
Human hearing is most sensitive
between __________, crucial for speech
perception.
3-4kHz
Sound waves travel through
the _____.
air
Waves enter the
___________, where they are
focused and amplified
outer ear
vibrates in response to sound waves
Tympanic membrane (eardrum)
Vibrations are transferred to
the _________ through the
_________.
cochlea, ossicles
tiny bones in the middle ear
ossicles
The cochlea, shaped like a
snail’s shell, contains ___________________.
3 fluid- filled tubes.
In the cochlea, sound vibrations are
transformed into ________________.
neural signals
responds to fluid waves created by the sound vibrations.
basilar membrane
What convert the vibrations into
electrical activity?
inner hair cells (about 16k of them)
In hearing, what converts
sound waves into neural signals?
mechanoreception
Inner hair cells’ unique structure
is crucial for __________.
hearing
Each cell has a ______________ that
response to basilar membrane
movement.
hair bundle
____________ between hairs open ion
channels when stretched.
Tip links
In hearing: What does the stretching of the tip links trigger?
triggers cell depolarization
and neurotransmitter release.
Adjacent regions respond to closely
related frequencies, forming ______________________.
a spatial frequency map.
_______________ deconstructs
complex sounds into simpler
frequency components for detailed
processing
Tonotopic mapping
In hearing: what organization does the Basilar membrane use?
Tonotopic organization
Sound signals are transmitted to the
_______________ in the brainstem.
cochlear nuclei
signals are relayed to the __________________ on both sides of the brainstem.
olivary nuclei
What is the auditory pathway?
auditory nerve -> cochlear nuclei -> superior olivary nucleus -> inferior colliculus -> MGN in the thalamus -> primary auditory cortex.
Neurons in the auditory cortex have what type of receptive fields?
frequency-dependent receptive fields
_______________ generally depends on the sound source’s position relative to the outer ear.
Sound localization
sounds from the side arrive slightly
earlier at the closer ear (by a few hundred microseconds)
Timing
sounds from the side are louder in the closer ear
Intensity
measures intensity differences
Lateral superior olive (LSO)
measures timing differences.
medial superior olive (MSO)
in the LSO: Neurons respond strongly when
_________________.
The sound is louder in the ear
closer to the source
The LSO’s output helps the brain
do what?
localize sound horizontally
In the MSO, neurons respond to what?
specific timing differences between the ears
In the MSO, what are Neurons tuned for?
to different delays
work together to localize sounds
based on timing disparities
In the LSO, what do neurons do?
compute loudness
differences between the two ears
What can result from damage to the outer or middle ear, or directly to the cochlea?
Deafness
Damage beyond the inner ear often causes _________________.
sound processing difficulties rather than total deafness
Damage to the primary auditory cortex can affect what?
sound localization
determining where sounds come from
sound localization
Damage to higher-order auditory cortex can affect what?
voice recognition and discerning
what is being heard
What amplifies sounds to assist
impaired auditory structures in perceiving and transmitting sounds?
Hearing aids
what bypasses a damaged
cochlea by converting sounds into electrical signals that stimulate the auditory nerve?
cochlear implants
What do cochlear implants NOT do? What do they do instead?
restore hearing, but can enable functional sound perception
Skin has________ layers with mechanoreceptors that detect
pressure, vibration, and movement?
3
Most mechanoreceptors are located in the ___________
dermis (middle layer of skin)
The ____________ acts as a barrier against pathogens and regulates water.
epidermis (outer layer)
What are the 4 key mechanoreceptors?
Merkel’s discs, Ruffini endings,
Meissner’s corpuscles, and Pacinian corpuscles.
Why do mechanoreceptors differ in location, structure, and response?
it enables detection of diverse touch stimuli.
Meissner’s corpuscles and Merkel’s disks are in _____________ and contain _______ receptive fields (~mms).
superficial layers, small
What do Meissner’s corpuscles and Merkel’s disks detect?
Detect fine, light touch with differing adaptation speeds
Pacinian corpuscles and Ruffini’s endings are found in _____________ and have _________ receptive fields (~cms).
deeper layers, larger
What do Pacinian corpuscles and Ruffini endings detect?
Detect stronger, more generalized pressure.
Receptors that relay temperature information
Thermoreceptors
Cells fire at slow, steady rate; what does temperature changes do to these firing rates?
temperature changes alter
firing rate.
receptors that relay pain information:
Nociceptors
What are the 3 types of nociceptors?
1) mechanical activated by physical damage
(2) thermal responds to extreme hot / cold
(3) chemical activated by toxins, poisonous gases, and several cooking spices
What does the signal speed on nociceptors depend on?
on fiber diameter and myelination,
affecting pain perception.
awareness of body position and
movement.
Proprioception
Receptors in _____________ provide information about limb position and movement.
muscles and joints
1) Detects muscle length and stretching speed.
(2) Found in higher density in muscles used for fine motor tasks
Muscle spindles
Measures muscle tension and prevent damage by limiting overcontraction.
Golgi tendon organs
What receptors enable precise object
manipulation and help maintain balance?
Proprioceptive receptors
Except for the head and face
(trigeminal pathway), somatic
sensory signals travel to the cortex
via the ____________.
spinal cord
Receptors send signals through
_____________ of dorsal
root ganglion neurons.
primary afferent fibers
The body is divided into skin
regions called __________, each
connected to specific dorsal root
ganglia.
dermatomes
Do touch pathways decussate?
YES
Is the somatosensory pathway contralateral or ipsilateral?
Contralateral
Body map in S1 reflects receptor density and sensory importance, not physical size.
Homunculus
Where does decussation occur in the somatosensory pathway?
in the brainstem
After decussation in the brainstem, signals travel to the ___________.
Thalamus (ventral posterior nucleus)
After decussation in the brainstem, and after reaching the VPN in the thalamus, the signals then reach where?
S1 (primary somatosensory cortex)
Damage to higher somatosensory regions causes what?
tactile agnosia
inability to identify objects by touch
tactile agnosia
What senses fall under proprioception?
- joint position sense
- kinesthesia
- sense of force
- Sense of change of velocity
What are the chemical signals in smell?
oderants
Odorants (chemical signals) enter through the nose or mouth and reach the ________________.
olfactory epithelium
binds to odorants and generate electrical signals.
Olfactory receptors
What type of neuron are olfactory receptors?
Bipolar neurons
Receptors recognize odorants based on ______________, not the overall odor.
molecular features
Each receptor responds to multiple odorants with
shared molecular characteristics. What is this called?
pattern encoding
Axons from similar receptor types converge on an
_____________ in the olfactory bulb
olfactory glomerulus
receives these signals,
preserving odor specificity
Mitral and tufted cells
Describe the Olfactory pathway
The olfactory pathway begins with odor detection in the olfactory epithelium, continues through receptor neurons sending signals to the olfactory bulb, and then travels via mitral and tufted cell axons in the olfactory tract to the primary olfactory cortex for initial perception. Subsequent projections connect to the orbitofrontal cortex, amygdala, hippocampus, and other areas, integrating smell with emotions, memories, and cognition.
In smell: what bypasses the thalamus, connecting directly to the cortex; enabling direct influence on brain
areas involved in memory and emotion?
Olfactory pathway
in smell; what receives input
from the bulb?
Primary olfactory cortex
In the olfactory pathway; where are signals relayed to?
Signals are relayed to the hippocampus, amygdala, and indirectly to the reticular formation and hypothalamus.
Smell is key for ______________ in many animals.
identifying “what” and
“where,”
Where are taste receptors located?
tongue, palate, pharynx, epiglottis, and esophagus
what detect tastants (pure taste stimuli)?
Taste cells
Taste cells cluster into ____________ and further group
into ___________.
taste buds, papillae
what depolarizes taste cell membranes to
initiate perception?
Tastants
What are the 5 categories of tastants?
sweet (sucrose), salty (sodium chloride), bitter (quinine), sour
(citric acid), and umami (MSG)
What type of neurons relay taste signals from taste cells to the brainstem?
Primary gustatory afferent neurons
In the Gustatory pathway, can each afferent fiber connect to multiple taste buds
with various taste cells or a single taste bud with various taste buds?
multiple taste buds
with various taste cells
Stimulus activation produces a unique receptor activity
pattern
pattern coding
Describe the Gustatory pathway
- Primary gustatory afferent neurons relay taste signals
from taste cells to the brainstem.
Signals proceed to the thalamus, then the primary
gustatory cortex (frontal operculum), and finally to the
insula (secondary taste areas).
What does damage to the primary gustatory cortex result in?
impairs taste perception, whereas damage to the insula affects food recognition and flavor intensity.
is a small portion of the electromagnetic spectrum, which consists of energy
traveling in waves.
Human visible light.
How is light emitted?
by sources like the sun, stars, fire, and lightbulbs
What do most objects do to light, rather than emitting it?
Most objects reflect
Color (hue)
wavelength
Brightness
amplitude of waves
Saturation
light complexity
ring of colored muscle fibers in the eye
Iris
central opening of the
iris
Pupil
What controls how much light enters the eye passing through the pupil?
Iris
Light then travels through the ________, which focuses the image onto the ___________ at the back of the eye/
Lens, retina
The retina is a multi-layered structure
containing __________________:(rods and cones)
light-sensitive receptors
- more numerous in humans and sensitive dim light.
- Detect variations in light intensity.
- Many rods converge onto a
single output cell, reducing spatial precision.
Rod receptors
- 10-100x less sensitive than rods and function
best in bright environments. - Enable color vision via 3 types that respond to
different light frequencies. - Each cone connects to an individual output sell,
prese and provide high acuity.
Cone receptors
What are activated after light activates the pigment molecules and causing a change in membrane potential?
Bipolar cells
What do bipolar cells stimulate?
ganglion cells
What transmits electrical
signals to the brain via the optic nerve?
Ganglion cells
Light entering the eye triggers a _____________ in the rods and cones.
photochemical reaction
Light activates ________________ (e.g., rhodopsin) in the receptors.
pigment molecules
What does light activating pigment molecules in the receptors cause?
It causes the pigment molecules to break apart and alter the membrane potential, initiating neurotransmitter signaling.
Adaptation mechanisms help the retina adjust to ambient
illumination by:
(1) pupil size adjustment
(2) switching between rods and cones
(3) photopigment regeneration
(4) lateral inhibition
Reduces responsiveness to constant stimulation, allowing focus on changes in input.
Sensory adaptation
Light intensity varies over _______________, from starlight to bright sunlight
1 million-fold
_____________ must remain sensitive across a vast range
of ambient light intensities
Visual neurons
Describe the visual pathway
- Visual information travels from the retina
through the optic nerve to the thalamus. - Most retinal input is sent to the LGN; some projections reach the superior colliculus via the pulvinar.
- Nasal optic nerves from each eye cross at
the optic chiasm. - The LGN relays visual information to the
primary visual cortex (V1) in the posterior occipital cortex.
The ____________ of each eye is divided into left and
right halves
visual field
Information from the _____ visual field (from both
eyes) is processed by the ________ hemisphere
left, right
what type of mapping does the visual pathway use?
contralateral mapping
Right LGN receives input from the ________________.
left visual field
Left LGN receives input from the ______________.
right visual field.
Partial crossing of optic nerves ensures signals from one side of the visual field are
sent to the opposite hemisphere.
Optic chiasm
What is the topographic organization of audition?
Sound frequency map (tonotopy)
What is the topographic organization of tactile (touch)?
Body Map (Sensory homunculus/ somatotopic arrangement )
What is the topographic organization of vision?
Visual field map (retinotopy)
The detection and conversion of physical energy (stimuli) from the environment into
neural signals, forming the foundation for perception.
Sensation
The process of selecting, organizing, and interpreting sensory information to create
meaningful experiences
Perception
each retinal ganglion
cell responds to stimulation in a specific area
of visual space
Visual receptive field
Ganglion cells maintain a ______________ organization
center-surround
maximally active when light
stimulates the RF center
on-center cells
respond to light in the
surround by not the RF center.
off-center cells
Through ______________, cells are optimized for detecting local differences in light levels (e.g., edges)
lateral inhibition
is a weighted sum of stimulus intensities, with positive weights in ON subregions
and negative weights in OFF
subregions.
Ganglion cell response
are summed, weighted
by positive (center) and negative (surround) values in the receptive field
Light intensities
a pattern of activity across the spatial array of ganglion cells.
neural image
what exhibits over/undershoots at edges due to lateral inhibition?
Ganglion cells
What emphasizes edges (differences in light
levels)?
center-surround receptive fields
contrast between slightly differing shades
of gray is exaggerated
Mach bands
In the mach band illusion, what makes the darker area appear darker and the lighter area appear lighter along the boundary?
Lateral inhibition
in vision: what balances inhibition and excitation?
receptive fields
A receptive field on a lighter band generates what? why?
a stronger response because part of its surround overlaps with the darker areas
The receptive field on a darker band receives what? why?
more inhibition due to part of its surround overlapping with
the brighter area.
What does the optic flow hypothesis suggest?
That crossing pathways help coordinate responses to
visual input, where obstacles on one side require motor responses from the opposite side
_______________________ enhances sensorimotor coordination and reflex integration, helping
with balance, error correction, and efficient movement.
Contralateral control
What is the relationship between thermoreceptors and nociceptors?
Thermoreceptors detect changes in temperature, signaling sensations of warmth or cold, while nociceptors are pain receptors that respond to potentially damaging stimuli, including extreme temperatures, meaning that while some thermoreceptors can signal discomfort at very high or low temperatures, they are distinct from nociceptors which primarily trigger pain sensations when activated by extreme stimuli; essentially, thermoreceptors are responsible for normal temperature perception, while nociceptors are activated when the temperature reaches a level that could cause tissue damage.
Begins with the sense receptors and progresses to the brain.
Perceptual analysis
What guides further construction of perceptions?
Higher-level mental processes
perceived brightness or color
of an object remains constant under varying illumination.
Lightness constancy
What is essential for recognizing objects as having consistent properties regardless of lighting?
Lightness constancy
Perception of edges, shapes, and forms is influenced by what?
both sensory input and the brain’s interpretation based on context and past
experiences.
The tendency to perceive object colors as stable despite changes in environmental
conditions (e.g., lighting)
Color constancy
Perceptual mechanism where
objects are perceived as maintaining consistent size,
even when their distance changes.
Changes in distance alter the size of the image
projected onto the retina, but not our perception of
the object’s size
Size constancy
What are examples of perceptual constancies?
shape constancy, size constancy, color constancy, lightness contancy
Perceptual tendency to
maintain the perception of an object’s shape, even as the viewing angle changes.
* Changes in viewing angle alter the shape of
the object’s retinal image but not our perception.
Shape constancy
What causes illusory motion?
Contrast and spatial arrangement of adjacent colored segments create the illusion of motion in static
images.
* Likely involves higher-level visual processing, beyond the initial retinal input
What does the illusory motion demostrate?
the complexity of
motion perception and how
interactions between visual
pathways can misinterpret static patterns as movement.
Describe the Ponzo illusion
Two identical horizontal lines appear to be different
in length due to their visual cortex. Often occurs with converging lines or
perspective cues that mimic a three-dimensional scene (e.g., railway tracks). The line closer to the converging point
(or further away in the scene) appears longer than the one closer to the viewer, despite being the same length.
What does the ponzo illusion do that leads to misjudgments of the line lengths?
it exploits the brain’s depth cues
In the ponzo illusion, ________________ make the brain assume
that objects farther away must be larger if
they occupy the same visual space
Perspective cues
What does the ponzo illusion demonstrate/highlights?
Demonstrates how size perception depends on context and how the brain constructs reality from visual cues.
Highlights the interaction between visual
cues and the brain’s assumptions about the
3D world based on 2D retinal images.
Fundamental organizing
principles in perceptual psychology.
* Emphasize the generative nature of perception,
where our brain adds to sensory input.
Gestalt principles
Perceived edges and shapes
that aren’t physically present.
Illusory Contours
Ambiguous stimuli that can
switch between alternative interpretations
Multi-stable images
What are the gestalt principles of visual processing evident in?
illusory contours and multi-stable images
What are the organizing principles of the visual system?
- Topographic organization
- Hierarchy of processing
- Specialized pathways
- Functional specialization
Systematic representation of visual space across the cortical surface (orthogonal to cortical depth).
* Neighboring neurons along the cortical surface receive input from adjacent parts
of the retina, representing adjacent parts of visual space
Retinotopy
The visual field is _____________ across the retina, a common feature in all vertebrates.
inverted
Each hemisphere processes the ________________ visual field
contralateral
___________ representation is not a direct replication but a reconstructed
version of the environment, shaped by the brain’s processing
Sensory
_____________ is not an exact replica of sensory input; it is a reconstruction shaped by the
brain.
Perception
certain sensory regions (e.g., fovea or fingertips)
are represented by disproportionately larger cortical areas; it enhances resolution and discrimination in highly sensitive
regions, enabling more detailed perception and precise interpretation of stimuli.
Cortical magnification
Foveal stimuli have the __________, essential for object vision
highest acuity
What happens to detection at greater retinal eccentricities?
detection slows and becomes less accurate
What is needed to maintain clarity?
peripheral stimuli must be larger
The brain maintains ______________ from V1 to higher areas, preserving
the spatial organization of the visual scene
multiple interconnected
visual maps
Most retinotopic maps are multifaceted. What kind of neurons are present?
neurons responding to multiple features.
What does retinotopic organization support?
supports spatial structure,
enabling integrated and flexible perception
What happens in the are of LGN neurons projecting to the V1? What does this enable?
LGN neurons project to V1,
where multiple inputs
converge onto single V1
neurons, enabling spatial
summation and the
development of orientation-
selective receptive fields
cells in V1 that emerge
from this convergence and
respond selectively to specific
orientations (e.g., vertical or
horizontal lines)
simple cells
cells that integrate
inputs from multiple simple
cells; They respond to more
advanced visual features, such as motion and texture
orientation; refines the
processing hierarchy,
supporting higher-level visual
analysis.
V1 complex cells
- layer IV
- prefers bars of light or bars
of dark - orientation selective
simple cells
- layers IV & II/ III
- responds to both bars of
light and dark - motion sensitive
- orientation selective
complex cells
- sensitive to length (short)
- aka end-stopping
Hypercomplex cells
Most V1 neurons respond
strongly to lines, bars or edges at a ______________, but
not to the orthogonal
orientation.
specific orientation
What does orientation selectivity in the V1 illustrate?
This illustrates the highly
selective nature of orientation
tuning in V1 neurons, which is
crucial for early visual
processing.
What has a columnar architecture?
V1
what is the columnar architecture of the V1 for?
ocular dominance and
orientation tuning.
What is going on with neurons moving perpendicular within a column?
neurons share the same
orientation preference and ocular dominance
What is going on with neurons moving tangentially across columns?
neurons systematically
vary in orientation and ocular
dominance.
Is a ~1mm block of cortex
containing a full set of orientation columns and
ocular dominance columns for a given retinotopic
location.
Hypercolumn
What structure ensures all orientations and both
eyes’ inputs are represented within a single
visual field location?
Hypercolumn
Within the grid of orientation and ocular dominance columns are blobs, which are
specialized for ________________.
color processing
_______________ receive input from adjacent
areas of the retina (via LGN) and perform similar visual
processing functions.
Neighboring cortical regions
Neurons in each visual area receive what?
converging inputs from preceding areas
Later areas integrate earlier inputs, what does this enable?
neurons to encode increasingly complex visual features along the hierarchy.
What happens to the receptive field size along the hierarchy? what does this allow for?
receptive field size increases further along the hierarchy, allowing for broader
integration of visual information
While feedforward processing is emphasized, lateral connectivity and
feedback play key roles in what?
refining perception based on context, experience, and expectations.
In early visual areas, neurons have ____________
receptive fields and respond to what?
small, simple features
like edges and orientation
Higher visual areas with __________ receptive fields
do what?
larger, integrate inputs from multiple lower-level
neurons.
where the brain fills in missing information to perceive complete shapes; Demonstrates the brain’s ability to infer wholes
from incomplete parts.
global pattern perception
Extrastriate areas show __________ activity
to Kanizsa figures when oriented to facilitate a perceived square compared
to non-coherent orientations
greater
What does the fact that Extrastriate areas show greater activity
to Kanizsa figures when oriented to
facilitate a perceived square compared
to non-coherent orientations reflect?
Likely reflects integration of corner information in regions with large receptive fields.
What does the fact that Extrastriate areas show greater activity
to Kanizsa figures when oriented to
facilitate a perceived square compared
to non-coherent orientations illustrate?
Illustrates hierarchical processing,
where higher-level areas synthesize
lower-level inputs to construct
complex visual features
What are the 2 types of ganglion cells in the retina?
m-cell and p-cell
Size of cell bodies of p-cells
smaller
Size of cell bodies of m-cells
larger
Size of receptive fields of p-cells
smaller
Size of receptive fields of m-cells
larger
Are p-cells color sensitive?
YES
Are m-cells color sensitive?
NO
What type of response do p-cells have? what do they respond to?
sustained, responds to fine detail, color
What type of response do m-cells have? what do they respond to?
transient, responds to coarse detail, motion
What pathway are p-cells apart of?
parvocellular pathway
What pathway are m-cells apart of?
magnocellular pathway
(occipital → parietal) processes spatial location, movement, and relationships, aiding in
navigation and movement coordination
dorsal pathway
(occipital → temporal) specializes in object identification, face recognition, and fine detail
perception, determining what we see
Ventral pathway
Where does the convergence of the dorsal and ventral pathway occur and what does it do?
these pathways converge in
higher-order frontal regions to integrate spatial and
identity information
motion processing, supported by specialized regions like MT (middle temporal area)
Where pathway
MT neurons are finely tuned to direction and speed, enabling detection of object
trajectories and velocities.
where pathway
tuning allows for precise motion interpretation, supporting navigation
and understanding of dynamic environments.
Where pathway
area processes
complex motion stimuli, such as plaid patterns
MT (middle temporal)
Forms when two gratings of
different orientations move orthogonally to
their own orientation.
a plaid stimulus
Humans perceive cohesive motion in the……….? What does this illustrate?
direction of intersection, illustrating how MT integrates multiple motion cues into a unified perception of movement.
(loss of color vision) is linked to ventral temporal damage (e.g., V4)
Achromatopsia
(deficit in motion perception) is associated with lateral occipito-temporal
damage (e.g., MT)
Akinetopsia
Activity in V4 and V4a aligns more closely with what? what idea does this support?
perceptual color space than raw sensory input; Supports the idea of a gradual shift from sensory to perceptual processing as visual information moves further from the sensory organs
The _____________ plays a key role in color perception, crucial for object
recognition and detailed visual analysis
ventral stream
Areas such as V4 and V4a are
specialized for what?
processing color information, enabling us to discern, categorize, and interpret chromatic features
detect global motion in plaid patterns, exhibiting
single-lobed tuning centered on the overall
motion direction.
Pattern cells
respond to individual
grating movements, showing two tuning
peaks aligned with each component’s motion
direction
Component cells
exhibit broad
tuning without clear double peaks, suggesting
a role in bridging global and local motion
processing.
Intermediate neurons
