Term
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Definition
NOT passively view the world
Actively interrogate and mentally reconstruct our environment.
To accomplish this, we can move
Our eyes (together)
Our head
Our body
Our body in a moving vehicle |
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Definition
to thalamus to occipital cortex, V1-8
Attached with muscles (move eye around,) |
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| injury- why you check eye movement and pupil dilation |
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Definition
| Muscles innervated by different cranial nerves. |
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Term
| cranial nerves related to vision |
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Definition
| Can look for intact nerves to determine ability to move eyes in desired direction. Cranial nerve 2 is occcular, 3- motor, 4- and 6 |
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Term
| best method to test eye motion |
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Definition
| ask the patient to follow your finger drawing a large H pattern in the air a few feet from their face. The two legs of the H will isolate and test the motion of the superior/inferior rectus pair and inferior/superior oblique pair. The center part of the H will test the medial and lateral muscles. |
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Definition
| hole in visual field, may not be aware. Missing information and fill in the gaps. |
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Definition
| where optic nerve is leaving eye and no receptors. |
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| clinical correlates of differences in pupil size, extreme variation in pupil size. |
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Definition
| addiction/ seizures/ stimulants/ hypnotics- |
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Definition
Sensitive to light, brightness, movement
connect to single ganglion cell than cones, therefore sum info over larger areas of the retina.
Located in the periphery of the eye.
Provide info to magnocellular system |
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Definition
| related to movement. Autism- hypoactive, more sensitive to movement. |
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Term
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Definition
Concentrated in the center (fovea and surrounding macula) of the eye.
Sensitive to color.
Almost one-to-one connection to ganglion cells, therefore very specialized for detail.
Provide info to parvocellular system |
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Term
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Definition
| increase surface area to allow for more cones in back of eye |
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Definition
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Definition
| problems with details, acuity. |
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Definition
| area around fovea, slightly less dense cones, some rods, degeneration (loss of cones) magnify stimuli. Interpret with magnocellular system instead of parvocellular system |
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Term
| one type of problem with cones |
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Definition
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Term
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Definition
the optic nerve via the optic chiasm (where it becomes the optic track) to
the thalamus (lateral geniculate nucleus or LGN) to
the primary visual cortex (V1) to
associative visual cortex (V2, V3, V4) to
dorsal (where) and ventral (what) pathways.
Perception is conscious. |
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Term
| another term for primary vision pathway |
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Definition
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Term
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Definition
| from ganglion to lateral genicular nucleus in thalamus to the primary visual cortex VI (conscious) |
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Term
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Definition
Optic nerve via optic chiasm becomes optic track, projects directly to superior colliculus (tectum).
Superior colliculus projects to the pulvinar nucleus of the thalamus.
Also receives input from visual cortex, and from LGN, thus feedback loops exist between almost all areas. |
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Term
| another term for secondary visual pathway |
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Definition
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Term
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Definition
tectopulvinar via optic nerve to optic chiasm half go to ipsalater to superior colliculus and tectum (nonconscious)
ie dogs without primary vision, still have indirect pathway and could navigate visual field |
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Term
| how vision influences the sleep/wake cycle |
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Definition
Light affects our arousal level.
Fibers from the ganglion cells of the retina (part of the optic nerve) ascend upwards into the suprachiasmic nucleus when they reach the optic chiasm.
The suprachiasmic nucleus (part of the hypothalamus) is involved in a number of functions, most particularly setting our biological clocks. It projects to the pineal gland, which in turn regulates production of melatonin. |
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Term
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Definition
| setting our biological clocks. It projects to the pineal gland, which in turn regulates production of melatonin. |
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Term
| pathway related in blindsight |
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Definition
| tectopavilar secondary pathway intact, but primary visual pathway disrupted |
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Term
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Definition
| studied blindsight- watched a movie on Mr. Young in class |
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Term
| projection of fibers to calcarine fissure |
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Definition
Some loop forward into temporal lobe- damage to vision, lose parts of visual field
Completely reversed (top to bottom, left to right) RIGHT TOP VISUAL FIELD to left temporal lower occipital
Meyer’s loop, light from visual field goes to top of retinal area. |
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Term
| biggest part of visual cortex |
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Definition
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Term
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Definition
| primary visual cortex surrounds this structure |
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Term
| damage to one side of V1 in one hemisphere |
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Definition
| color blindness in the opposite side of the visual field |
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Term
| information from center of visual field goes here |
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Definition
| represented in the area furthest in the back of the occipital lobe and most medially |
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Term
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Definition
integrate patches of information from the retina (via the thalamus) into lines, shapes, movement, and colors.
At the more advanced level, shapes come together into complex patterns such as faces (first sorted by gender, then by individual) and buildings. |
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Term
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Definition
| lateral geniculate neurons axons to VI- selective cortical cells, respond to thalamic cells that fire or don’t fire. Integrates into shapes as you go through visual cortex areas |
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Term
| deficits in temporal lobe related to vision |
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Definition
| can tell you gender, but can’t tell more details or who individual is. |
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Term
| simple cells related to vision |
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Definition
| found in Layer IV (in the middle of the six cortical layers), and are sensitive to lines of a particular orientation or angle. |
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Term
| complex cells related to vision |
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Definition
| found in the remaining layers and combine information from simple cells |
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Definition
| Both certain simple and certain complex cells respond best to lines that stop in their visual field; mind likes to create forms/ whole objects- weird when lines stop, creates meaning |
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Definition
| if they recorded from an electrode at one point in the primary visual cortex (aka Area 18), and then moved the electrode a hair’s breadth over and recorded again, the next column of cells responded best to a line that was oriented about 10 degrees more. Over a distance of about 1mm, lines responding to the entire 180 degrees could be found. |
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Term
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Definition
| Cortical cells in the visual cortex receive input from both eyes. However, they are more sensitive to input from either the left or the right eye |
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Term
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Definition
| one section of cells that respond maximally to cells with left eye input, and adjacent to it a row of cells maximally responsive to right eye input |
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Definition
| Interspersed between columns of cells sensitive to line orientation are cells that respond to color |
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Definition
| blob cells are not joined together, and cells in-between are like the other cells, and sensitive to line orientation |
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Term
| information from magnocellular system goes here |
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Definition
| goes to cortical areas V1, V2, and V3, and then projects to an area of association cortex called V5 or MT (medial temporal cortex). This area is maximally responsive to motion. |
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Term
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Definition
failure to detect movement, deficit in V5
normal acuity and color vision, but could not detect three-dimensional movement (versus simple linear motion of a line going back and forth).
Intersections, pouring tea, etc. were very challenging for her. |
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Term
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Definition
| the visual field from the retina is precisely mapped onto the cells of V1. |
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Term
| simple vs complex cells responses |
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Definition
| (in primary visual cortex) in layer 4 are sensitive to line orientation and direction of movement VS are sensitive to line combinations, angles, corners. |
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Term
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Definition
association cortex, where cells are responsive to
orientation, color and form, as in V1.
Additionally, they respond to orientation of illusory contours and whether the stimulus is part of the figure or the ground. |
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Term
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Definition
| may play a role in the processing of global motion |
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Definition
| responsive to orientation, spatial frequency, and color. Also strongly influenced by selective attention; gets a lot of input from V2 |
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Definition
| – perception of motion, also known as MT (middle temporal region). Gets input from pulvinar area of LGN as well as V1,V2,and V3. |
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Term
| Dorsal up toward parietal visual pathway |
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Definition
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Term
| Ventral down toward temporal visual pathway |
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Definition
| what pathway, identify object |
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Term
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Definition
| visuomotor deficit, where an individual is unable to accurately perform goal-directed actions to visual targets, but their perception of where the target is in space is left intact. grab an object, i.e. a tennis ball, they would be able to verbally identify where it was and how big it was, but when they go to reach for it, they fail to reach in the right direction and would also fail to adjust their hand to the appropriate size needed to pick the ball up. |
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Term
| optic ataxia- deficit in this stream |
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Definition
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Term
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Definition
| John in the movie. Inability to put together larger pieces of a visual whole such as a face to form a gestalt |
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Term
| apperceptive agnosia- deficit in this stream |
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Definition
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Term
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Definition
| Larry in the movie. Inability to associate a complex visual form with its associations / memories in other modalities – i.e. who the person is based on memory and experience. In Larry’s case the deficit was also associated with a disconnection between visual images and their emotional associations, although at an unconscious level his skin conductance revealed some remaining awareness of who the person might be. Thus he no longer had “the pleasure of a pretty girl’s face” even though he could enjoy literature – the words travel to the limbic system via a separate route. |
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Term
| associative agnosia- deficit in this stream |
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Definition
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Term
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Definition
where complex patterns and objects are processed
neuron fire for specific face |
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Term
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Definition
look like person, but actually an imposter (ie doctor or family member)
due to a disconnection between the limbic system and the dorsal stream, such that the person is not experiencing the complete physiological reaction they normally have to a person and interprets this as “something is not right”, the person really isn’t the right person.
The syndrome only applies to the visual system – auditory input travels via a different route than the visual stream to the limbic system and therefore the fibers are intact and voices produce the usual reaction. |
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Definition
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Term
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Definition
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Definition
| ability to perceive light, contrast, targets, and fields |
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Definition
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Term
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Definition
| 1/2 of visual field on same side on each eye is blind (neural, not physical part of eye) (i.e. both right sides of visual field is missing |
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Term
| primary visual processing center |
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Definition
| area V1 (striate cortex) most posterior part of the occipital lobe |
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Term
| secondary visual processing center |
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Definition
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Term
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Definition
| cortical blindness in V1, but can indicate a stimulus is present/ has moved. automatic processing, not total damage to visual pathway |
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Definition
| loss of color, deficit in V4 |
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Term
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Definition
| inability to identify an object in motion, deficit in V5 |
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Term
| neuroplasticity in blind people |
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Definition
| occipital lobe/ V1 activates when handling objects in hands, blind individuals have superior verbal memories, increased activation in occipital when reading braille not show in non-blind individuals |
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Term
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Definition
| fail to recognize objects |
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Term
| what happens to light when it enters eye |
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Definition
| o Light gets bent and focused by the cornea, enters the eye through the lens and pupil, passes through the blood vessel filled vitreous fluid, photons hit photoreceptors in the back of the eye on the retina |
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Term
| eye muscles that control eyeball |
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Definition
Inferior/superior pair
Inferior/superior oblique |
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Term
| catty-corner projection of visual fibers |
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Definition
•top left visual field runs through the bottom right temporal lobe to bottom right occipital lobe
•Block design is good at testing this! |
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Term
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Definition
association with memories, feelings etc.
•can see and understand what an object is but cannot associate the image with memories, emotions |
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Definition
gestalt deficit
• has trouble putting together images into a composite. Can “see” everything ok just has trouble integrating to understand what it is |
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