Visual-Vestibular Interaction Hypothesis for the Control
... produce a motor error signal that drives the burst cells. •Improvements of Robinson’s model rely on a dynamic motor error signal produced by a “comparator” that drives the burst neurons during the saccadic fast phase. Most models either attribute its role to the superior colliculus (SC) or place it ...
... produce a motor error signal that drives the burst cells. •Improvements of Robinson’s model rely on a dynamic motor error signal produced by a “comparator” that drives the burst neurons during the saccadic fast phase. Most models either attribute its role to the superior colliculus (SC) or place it ...
Lecture 3
... •The cortex is a folded sheet of cells, about 2 mm thick. •The cells form layers (6 layers in primary visual cortex). •If move perpendicular to the surface of the cortex, cells will respond primarily to input from one eye (ocular dominance). •The pattern of responses forms columns of ocular dominanc ...
... •The cortex is a folded sheet of cells, about 2 mm thick. •The cells form layers (6 layers in primary visual cortex). •If move perpendicular to the surface of the cortex, cells will respond primarily to input from one eye (ocular dominance). •The pattern of responses forms columns of ocular dominanc ...
Lec17BioImProc
... Center-surround organization: 1. Light hyperpolarizes the rod and excites the bipolar cell below it ...
... Center-surround organization: 1. Light hyperpolarizes the rod and excites the bipolar cell below it ...
Modification of brain circuits as a result of experience
... How do neurons know that they are around others of the same eye? Hebb’s postulate • When an axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as ...
... How do neurons know that they are around others of the same eye? Hebb’s postulate • When an axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as ...
Session 4
... Simple cells: Elongated Receptive fields. Orientation selective. Defined regions of excitation and inhibition. Complex cells: Also orientation selective. No well defined regions of excitation and inhibition. Hypercomplex cells: End-stopped. ...
... Simple cells: Elongated Receptive fields. Orientation selective. Defined regions of excitation and inhibition. Complex cells: Also orientation selective. No well defined regions of excitation and inhibition. Hypercomplex cells: End-stopped. ...
An adult is experiencing inferior alternating hemiplegia. Which
... Axons in the pyramid on the left side of the medulla and adjacent axons of the hypoglossal nerve are injured. Which statement best describes the condition? A) It is associated with the posterior cerebral artery. B) Muscles of the lower face are weak on the right side. C) The protruded tongue deviat ...
... Axons in the pyramid on the left side of the medulla and adjacent axons of the hypoglossal nerve are injured. Which statement best describes the condition? A) It is associated with the posterior cerebral artery. B) Muscles of the lower face are weak on the right side. C) The protruded tongue deviat ...
Lecture 13A
... • It corrects these errors, learning to confine the call to the correct member of each category, and to respond more quickly. • However, even when the vervet produces its first calls, it does not make between-category errors, for example, issue the snake call to a bird, and so on. • That means they ...
... • It corrects these errors, learning to confine the call to the correct member of each category, and to respond more quickly. • However, even when the vervet produces its first calls, it does not make between-category errors, for example, issue the snake call to a bird, and so on. • That means they ...
Laboratory 9: Pons to Midbrain MCB 163 Fall 2005 Slide #108 1
... 1,2,3 These are all laminae of the superior colliculus. 1 is the superficial layer, 2 is the intermediate layers, and 3 is the deep gray. Within its layers are many different sensory maps (vision, audition, somatic sensation), that all come into register with one another (forward in visual space is ...
... 1,2,3 These are all laminae of the superior colliculus. 1 is the superficial layer, 2 is the intermediate layers, and 3 is the deep gray. Within its layers are many different sensory maps (vision, audition, somatic sensation), that all come into register with one another (forward in visual space is ...
Introduction
... green). The nerve fibers from each eye meet at the optic chiasm, where fibers from the inside half of each retina cross over to the opposite side of the brain. After reaching the optic chiasm, the major visual pathway projects through the lateral geniculate nucleus in the thalamus and onto the prima ...
... green). The nerve fibers from each eye meet at the optic chiasm, where fibers from the inside half of each retina cross over to the opposite side of the brain. After reaching the optic chiasm, the major visual pathway projects through the lateral geniculate nucleus in the thalamus and onto the prima ...
Lecture 7 (Jan 31): BRAIN DEVELOPMENT and EVOLUTION
... Sperry’s studies told us that there must be something “chemical” that directs projections from one part of the Retina to a specific part of the Optic Tectum Evidence for Chemical Markers (in vitro experiments) TOPDV, high concentration in Dorsal Retina, low in Ventral Retina AND high in Ven ...
... Sperry’s studies told us that there must be something “chemical” that directs projections from one part of the Retina to a specific part of the Optic Tectum Evidence for Chemical Markers (in vitro experiments) TOPDV, high concentration in Dorsal Retina, low in Ventral Retina AND high in Ven ...
Visual system - cloudfront.net
... Optic radiation carries the information to the visual cortex and to another part of the brain called the calcarine fissure. ...
... Optic radiation carries the information to the visual cortex and to another part of the brain called the calcarine fissure. ...
Slide ()
... The axons of retinal ganglion cells grow to the optic tectum in discrete steps. Two neurons that carry information from the nasal half of the retina are shown. The axon of one crosses the optic chiasm to reach the contralateral optic tectum. The axon of the other also crosses the optic chiasm but pr ...
... The axons of retinal ganglion cells grow to the optic tectum in discrete steps. Two neurons that carry information from the nasal half of the retina are shown. The axon of one crosses the optic chiasm to reach the contralateral optic tectum. The axon of the other also crosses the optic chiasm but pr ...
Innervation of the Eye and Orbit
... (nasal retina=temporal visual fields) Optic tract =>Loss of contralateral visual field Partial chiasm - unpredictable due to ...
... (nasal retina=temporal visual fields) Optic tract =>Loss of contralateral visual field Partial chiasm - unpredictable due to ...
Target innervation and LGN/colliculus development
... Wnt3 signaling mediated by Ryk appears to provide for lateral mapping. Ventral axons are repelled by Wnt3, while dorsal axons are attracted by low Wnt3 and repelled by high Wnt3. EphrinB1 activation of EphB2 and EphB3 receptors provides medial mapping by attracting axon branches. When Wnt3 repulsio ...
... Wnt3 signaling mediated by Ryk appears to provide for lateral mapping. Ventral axons are repelled by Wnt3, while dorsal axons are attracted by low Wnt3 and repelled by high Wnt3. EphrinB1 activation of EphB2 and EphB3 receptors provides medial mapping by attracting axon branches. When Wnt3 repulsio ...
Objectives 31
... - Cortical cells respond to stripes or edges with a particular orientation; simple cells have excitatory and inhibitory regions in the shape of oriented bars; complex cells respond to oriented lines of a particular length -other neurons are more concerned with color than with black/white contrast; t ...
... - Cortical cells respond to stripes or edges with a particular orientation; simple cells have excitatory and inhibitory regions in the shape of oriented bars; complex cells respond to oriented lines of a particular length -other neurons are more concerned with color than with black/white contrast; t ...
answers - UCSD Cognitive Science
... o prefrontal cortex: (formulating movement) - parietal lobe o primary somatosensory cortex: (located caudal to central sulcus) - temporal lobe o primary auditory cortex: (located on the ventral side of lateral fissure) - occipital lobe o primary visual cortex: (located around the calcarine fissure) ...
... o prefrontal cortex: (formulating movement) - parietal lobe o primary somatosensory cortex: (located caudal to central sulcus) - temporal lobe o primary auditory cortex: (located on the ventral side of lateral fissure) - occipital lobe o primary visual cortex: (located around the calcarine fissure) ...
THE VISUAL SYSTEM
... • Optic chiasm: pt at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain • Optic fibers then diverge along 2 paths • Main path projects into thalamus; retinal axons synapse in the Lateral geniculate nucleus (LGN) • Then to the occipi ...
... • Optic chiasm: pt at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain • Optic fibers then diverge along 2 paths • Main path projects into thalamus; retinal axons synapse in the Lateral geniculate nucleus (LGN) • Then to the occipi ...
poster - Stanford University
... neuromodulation by acetylcholine is a potential mechanism for evoking synchrony during bottom-up stimulus selection. ...
... neuromodulation by acetylcholine is a potential mechanism for evoking synchrony during bottom-up stimulus selection. ...
Visual Processing - West Virginia University
... Pattern of illumination that maximally excites ganglion cell is doughnut shaped Center-surround receptive field Lateral inhibition of receptive fields enhances boundaries ...
... Pattern of illumination that maximally excites ganglion cell is doughnut shaped Center-surround receptive field Lateral inhibition of receptive fields enhances boundaries ...
BehNeuro11#2 (2) - Biology Courses Server
... principle types of computations. What information is computed, and what is the relation between that information and the sound source location? (this is related to the ‘duplex theory’ of sound localization). ...
... principle types of computations. What information is computed, and what is the relation between that information and the sound source location? (this is related to the ‘duplex theory’ of sound localization). ...
Medial Longitudinal Fissure
... Corticospinal Tracts Receives afferents from sensory modalities and relay via Thalamus ...
... Corticospinal Tracts Receives afferents from sensory modalities and relay via Thalamus ...
Superior colliculus
The superior colliculus, (Latin, upper hill) is a paired structure of the mammalian midbrain. In other vertebrates this is known as the optic tectum or simply tectum, and the adjective tectal may also be used. The superior colliculus forms a major component of the midbrain. The tectum is a layered structure, with a number of layers that varies by species. The superficial layers are sensory-related, and receive input from the eyes as well as other sensory systems. The deep layers are motor-related, capable of activating eye movements as well as other responses. There are also intermediate layers, with multi-sensory cells and motor properties.The general function of the tectal system is to direct behavioral responses toward specific points in egocentric (""body-centered"") space. Each layer of the tectum contains a topographic map of the surrounding world in retinotopic coordinates, and activation of neurons at a particular point in the map evokes a response directed toward the corresponding point in space. In primates, the superior colliculus has been studied mainly with respect to its role in directing eye movements. Visual input from the retina, or ""command"" input from the cerebral cortex, create a ""bump"" of activity in the tectal map, which, if strong enough, induces a saccadic eye movement. Even in primates, however, the tectum 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 in walking rats, swimming fishes, or flying birds; tongue-strikes toward prey in frogs; fang-strikes in snakes; etc.In some vertebrates, including fish and birds, the tectum is one of the largest components of the brain. In mammals, and especially primates, the massive expansion of the cerebral cortex reduces the tectum (""superior colliculus"") to a much smaller fraction of the whole brain. It remains nonetheless important in terms of function as the primary integrating center for eye movements.Note on terminology: This article follows terminology established in the literature for the analogous structure in mammals/non-mammals (see above), using the term ""superior colliculus"" when discussing mammals and ""optic tectum"" when discussing either specific non-mammalian species or vertebrates in general.