Visual Pathways Flashcards
The PHENOMENON of HEMIDECUSSATION occurs at the _____________.
Optic Chiasm
The TWO (2) OPTIC NERVES, ONE from EACH EYE, are made up of ___________.
The axons of ganglion cells.
In regards to HEMIDECUSSATION, what portion of MEDIAL FIBERS cross to the other side?
1/2
Once 1/2 of the MEDIAL FIBERS have crossed to the other side, they are referred to as __________.
Optic Tracts
The OPTIC TRACT of EACH SIDE passes back to ___________ of the THALAMUS.
Lateral Geniculate Nucleus
The OPTIC TRACT of EACH SIDE passes back to ___________ and __________in the MIDBRAIN.
Pretectal Nucleus
Superior Colliculus
The LATERAL GENICULATE NUCLEUS sends IMPULSES TO __________ in the _________ and ___________ in the __________.
AREA 17 in the OCCIPITAL LOBE
PULVINAR NUCLEUS in the THALMAMUS
The PULVINAR NUCLEUS sends impulses to __________ and ________ in the __________.
AREA 18 and AREA 19
in the OCCIPITAL LOBE
The PRETECTAL NUCLEUS sends IMPULSES TO ____________ of the eye.
Intrinsic Muscles
SUPERIOR COLLICULUS sends IMPULSES TO ____________.
Cranial Nerve Nuclei III, IV and VI
Cranial Nerve Nuclei III, IV and V send IMPULSES TO ___________ of the eye.
Extrinsic Muscles
It has been concluded that there are ___ different FIBER GROUPINGS.
4
CONDUCTION RATES of the FOUR (4) FIBER GROUPS step down by __________.
Halves
PRIMARY DEGENERATION is also known as ____________.
Anterograde
SECONDARY DEGENERATION is also known as _______________.
Retrograde
The HIGH degree of POINT-TO-POINT projection of the RETINA upon LGN and that the LGN has on the STRIATE CORTEX means that the LGN is ______________ organized.
Topographically
CENTRAL VISUAL FIELD is represented by relatively _________ areas of the LGN.
Large
The CENTRAL VISUAL FIELD is where ____________ is considerably better than ____________.
Detailed Vision
Periphery
In the HUMAN there are ___ LAYERS in the LGN which are SERVED ALTERNATELY by the two eyes.
6
ELECTRICAL ACTIVITY in the CORTEX can be divided into _________ and _______ responses.
Fast
Slow
In the FAST response of the CORTEX the ________ sends impulses to _________ which sends impulses to _________.
Eye—–>LGN——>Area 17
In the SLOW response of the CORTEX the ________ sends impulses to _________ which sends impulses to _________ then finally to __________.
Eye—–>LGN——>Pulvinar——>Areas 18 & 19
In CONTRAST to the LGN, the organization of CORTICAL CELLS is _________.
Binocular
LGN INPUTS are activated by stimuli to EITHER EYE resulting in __________.
Binocular Mixing
This PHENOMENON occurs at the OPTIC CHIASM.
HEMIDECUSSATION
