Superior colliculus/optic tectum is a midbrain structure. The term superior colliculus is used when discussing mammals and optic tectum when discussing either specific non-mammalian species or vertebrates in general. It is a layered structure, with a number of layers that varies by species. The layers can be grouped into the superficial layers and the deeper layers. Neurons in the superficial layers receive direct input from the retina and respond almost exclusively to visual stimuli. The deeper layers contain a population of motor-related neurons, capable of activating eye movements as well as other responses. The superior colliculus mainly has its role in directing eye movements. Visual input from the retina, or an input from the cerebral cortex, creates a \"bump\" of activity in the tectal map, which, if strong enough, induces a saccadic eye movement (A quick and simultaneous movement of both eyes). In primates however, the superior colliculus is also involved in generating spatially directed head turns, arm-reaching movements, and shifts in attention that do not involve any overt movements. In other species, the tectum is involved in a wide range of responses, including whole-body turns etc. Solution Superior colliculus/optic tectum is a midbrain structure. The term superior colliculus is used when discussing mammals and optic tectum when discussing either specific non-mammalian species or vertebrates in general. It is a layered structure, with a number of layers that varies by species. The layers can be grouped into the superficial layers and the deeper layers. Neurons in the superficial layers receive direct input from the retina and respond almost exclusively to visual stimuli. The deeper layers contain a population of motor-related neurons, capable of activating eye movements as well as other responses. The superior colliculus mainly has its role in directing eye movements. Visual input from the retina, or an input from the cerebral cortex, creates a \"bump\" of activity in the tectal map, which, if strong enough, induces a saccadic eye movement (A quick and simultaneous movement of both eyes). In primates however, the superior colliculus is also involved in generating spatially directed head turns, arm-reaching movements, and shifts in attention that do not involve any overt movements. In other species, the tectum is involved in a wide range of responses, including whole-body turns etc..

1. Superior colliculus/optic tectum is a midbrain structure. The term superior colliculus is used
when discussing mammals and optic tectum when discussing either specific non-mammalian
species or vertebrates in general. It is a layered structure, with a number of layers that varies by
species. The layers can be grouped into the superficial layers and the deeper layers. Neurons in
the superficial layers receive direct input from the retina and respond almost exclusively to visual
stimuli. The deeper layers contain a population of motor-related neurons, capable of activating
eye movements as well as other responses. The superior colliculus mainly has its role in directing
eye movements. Visual input from the retina, or an input from the cerebral cortex, creates a
"bump" of activity in the tectal map, which, if strong enough, induces a saccadic eye movement
(A quick and simultaneous movement of both eyes). In primates however, the superior colliculus
is also involved in generating spatially directed head turns, arm-reaching movements, and shifts
in attention that do not involve any overt movements. In other species, the tectum is involved in
a wide range of responses, including whole-body turns etc.
Solution
Superior colliculus/optic tectum is a midbrain structure. The term superior colliculus is used
when discussing mammals and optic tectum when discussing either specific non-mammalian
species or vertebrates in general. It is a layered structure, with a number of layers that varies by
species. The layers can be grouped into the superficial layers and the deeper layers. Neurons in
the superficial layers receive direct input from the retina and respond almost exclusively to visual
stimuli. The deeper layers contain a population of motor-related neurons, capable of activating
eye movements as well as other responses. The superior colliculus mainly has its role in directing
eye movements. Visual input from the retina, or an input from the cerebral cortex, creates a
"bump" of activity in the tectal map, which, if strong enough, induces a saccadic eye movement
(A quick and simultaneous movement of both eyes). In primates however, the superior colliculus
is also involved in generating spatially directed head turns, arm-reaching movements, and shifts
in attention that do not involve any overt movements. In other species, the tectum is involved in
a wide range of responses, including whole-body turns etc.