Cerebrum rear {occipital lobe}| is for vision, perceptual judgment, memory, and association.
input
Occipital lobe receives from lateral geniculate nucleus, mostly onto layer 4 [Allman, 1998] [Allman and Kaas, 1971] [Zeki, 1974] [Zeki, 1993].
Layer 4 keeps input from two eyes separate. Alternating ocular-dominance-column bands, 0.5 millimeters wide, are for input from same ipsilateral side or opposite contralateral side.
Cortical layers above and below layer 4 have neurons that receive from both eyes. Binocular neurons differ slightly in eye connection alignment, allowing distance judgments.
Occipital lobe also receives from lower brain centers.
damage
Occipital lobe damage causes blindness. Cortical area V1, V2, and V3 damage affects perception and pattern recognition, leaving only ability to perceive intensity. Left-occipital lesion and corpus-callosum posterior-splenium lesion cause alexia without agraphia.
anatomy
Simple cells have well-defined excitatory and inhibitory regions in receptive fields [DeValois and DeValois, 1988] [Hubel and Wiesel, 1959] [Hubel and Wiesel, 1962] [Hubel, 1988] [Livingstone, 1998] [Spillman and Werner, 1990] [Wandell, 1995] [Wilson et al., 1990].
Complex cells do not have well-defined excitatory and inhibitory regions [Allman et al., 1985] [Gallant et al., 1997] [Lamme and Spekreijse, 2000] [Shapley and Ringach, 2000].
Complex-neuron receptive fields are larger than simple-neuron fields and have up to 100 degrees of visual angle.
processing
Some visual-cortex neurons distinguish between familiar and unfamiliar objects. Some neurons recognize faces. Some neurons respond only to face, hairbrush, or hand. Some neurons respond to face only if eyes point in direction. Some neurons store object locations. Some neurons predict eye-movement direction.
Biological Sciences>Zoology>Organ>Nerve>Brain>Cerebrum>Occipital Lobe
4-Zoology-Organ-Nerve-Brain-Cerebrum-Occipital Lobe
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Date Modified: 2022.0224