Widzenie
... figures were recognized, transient episodes of largescale synchrony appeared after the presentation of the stimuli, followed by a period of phase scattering and a second period of synchrony during the motor response. Such patterns of synchrony were not present when the pictures were not recognized. ...
... figures were recognized, transient episodes of largescale synchrony appeared after the presentation of the stimuli, followed by a period of phase scattering and a second period of synchrony during the motor response. Such patterns of synchrony were not present when the pictures were not recognized. ...
consist of receptors and accessory organs. Skin, visual organ
... The fundus of eyeball—internal surface of post. part of eyeball ① optic disc (blind spot ) ②macula lutea ( yellow spot) 3.5mm to the temporal side of optic disc ...
... The fundus of eyeball—internal surface of post. part of eyeball ① optic disc (blind spot ) ②macula lutea ( yellow spot) 3.5mm to the temporal side of optic disc ...
Epiretinal Membrane Information Sheet
... vision. Macular pucker or epiretinal membrane is caused due to scar tissue formation on the surface of the macula It is also known as cellophane maculopathy or premacular fibrosis. To maintain the contour, the eye ball is filled with a jelly like substance known as the vitreous. The vitreous is atta ...
... vision. Macular pucker or epiretinal membrane is caused due to scar tissue formation on the surface of the macula It is also known as cellophane maculopathy or premacular fibrosis. To maintain the contour, the eye ball is filled with a jelly like substance known as the vitreous. The vitreous is atta ...
Sensory physiology lecture
... horizontal cells, then bipolar cells, followed by ganglion and amacrine cells. It is in the ganglion and amacrine cells that the action potentials are generated. This is then sent to the optical nerve and from there, to the visual cortex of the brain. Slide #41: Scanning electron micrograph and draw ...
... horizontal cells, then bipolar cells, followed by ganglion and amacrine cells. It is in the ganglion and amacrine cells that the action potentials are generated. This is then sent to the optical nerve and from there, to the visual cortex of the brain. Slide #41: Scanning electron micrograph and draw ...
Light as a stimulus for vision Electromagnetic spectrum Radiant
... Rayleigh scattering is strongly wavelength dependent (1/λ4) and gives us the blue color of the sky. Mie scattering is not strongly wavelength dependent and produces the almost white glare around the sun when a lot of particulate material is present in the air. It also gives us the white light from m ...
... Rayleigh scattering is strongly wavelength dependent (1/λ4) and gives us the blue color of the sky. Mie scattering is not strongly wavelength dependent and produces the almost white glare around the sun when a lot of particulate material is present in the air. It also gives us the white light from m ...
Effect of wavelength on in vivo images of the human cone mosaic
... their results because the actual flux density at the photoreceptors produced by transscleral illumination was not measured directly. Prieto et al.11 and Burns et al.12,17 investigated the angular tuning of the light generated by fluorescence in the retinal pigment epithelium (RPE). They showed that ...
... their results because the actual flux density at the photoreceptors produced by transscleral illumination was not measured directly. Prieto et al.11 and Burns et al.12,17 investigated the angular tuning of the light generated by fluorescence in the retinal pigment epithelium (RPE). They showed that ...
outline5392
... and further anatomic details, where applicable, will be utilized: 1. Retinal a) Outer retina b) Inner retina 1) Papillomacular bundle – Ganglion cells arising from the fovea which represent the central 2 degrees of the visual field 2) Arcuate bundle – Fibers arising from the superotemporal and infer ...
... and further anatomic details, where applicable, will be utilized: 1. Retinal a) Outer retina b) Inner retina 1) Papillomacular bundle – Ganglion cells arising from the fovea which represent the central 2 degrees of the visual field 2) Arcuate bundle – Fibers arising from the superotemporal and infer ...
Chapter 58 Assessment and Management of Patients With Eye and
... vision), and color (color value shift to yellow-brown) Diagnostic findings include decreased visual acuity and opacity of the lens by ophthalmoscope, or inspection ...
... vision), and color (color value shift to yellow-brown) Diagnostic findings include decreased visual acuity and opacity of the lens by ophthalmoscope, or inspection ...
Taste sensation from the oral part (anterior two
... 2. Abnormalities of the thymus and superior and inferior parathyroid glands are exhibited by infants suffering from DiGeorge syndrome. These specific malformations indicate that DiGeorge syndrome affects development of which of the following pharygeal pouches? A. 1st only B. 1st and 2nd C. 2nd and 3 ...
... 2. Abnormalities of the thymus and superior and inferior parathyroid glands are exhibited by infants suffering from DiGeorge syndrome. These specific malformations indicate that DiGeorge syndrome affects development of which of the following pharygeal pouches? A. 1st only B. 1st and 2nd C. 2nd and 3 ...
Taste sensation from the oral part (anterior two
... 2. Abnormalities of the thymus and superior and inferior parathyroid glands are exhibited by infants suffering from DiGeorge syndrome. These specific malformations indicate that DiGeorge syndrome affects development of which of the following pharygeal pouches? A. 1st only B. 1st and 2nd C. 2nd and 3 ...
... 2. Abnormalities of the thymus and superior and inferior parathyroid glands are exhibited by infants suffering from DiGeorge syndrome. These specific malformations indicate that DiGeorge syndrome affects development of which of the following pharygeal pouches? A. 1st only B. 1st and 2nd C. 2nd and 3 ...
A new type of arthropod photoreceptor
... it is not a bona ®de tapetum lucidum because it lacks the typical multilayered re¯ectant cell structure). In summary, the anatomical and histological characteristics of the vesicle present in Vesicephalus suggest that it is ...
... it is not a bona ®de tapetum lucidum because it lacks the typical multilayered re¯ectant cell structure). In summary, the anatomical and histological characteristics of the vesicle present in Vesicephalus suggest that it is ...
Capability of the human visual system
... functions similarly to the aperture stop and shutter in a camera. The pupil, a variable diameter opening within the iris, determines the amount oflight that passes through to the retina, and is analogous to the camera's aperture. The iris in width to alter the size of the pupil as a function of the ...
... functions similarly to the aperture stop and shutter in a camera. The pupil, a variable diameter opening within the iris, determines the amount oflight that passes through to the retina, and is analogous to the camera's aperture. The iris in width to alter the size of the pupil as a function of the ...
June - the St. Louis Optometric Society
... light for our circadian rhythms to properly function. This is the blue light at the higher end of the blue light spectrum (450 and up). We are getting excessive amounts of all wavelengths of blue light from our digital devices; therefore, lack of blue light is never a problem. Just as not enough blu ...
... light for our circadian rhythms to properly function. This is the blue light at the higher end of the blue light spectrum (450 and up). We are getting excessive amounts of all wavelengths of blue light from our digital devices; therefore, lack of blue light is never a problem. Just as not enough blu ...
Sensory Physiology
... the optic disc is called the blind spot because no photoreceptors are present , only neural tissue. ...
... the optic disc is called the blind spot because no photoreceptors are present , only neural tissue. ...
Lab 4: Sensory Physiology
... ever been in a bright room and then enter a dark room you are momentarily blinded because your rhodopson in rod cells has been bleached and you cannot see. Therefore, rod cells work best in low light situations rather than with bright light due to rhodopsin bleaching. Cone cells (~ 3 million of them ...
... ever been in a bright room and then enter a dark room you are momentarily blinded because your rhodopson in rod cells has been bleached and you cannot see. Therefore, rod cells work best in low light situations rather than with bright light due to rhodopsin bleaching. Cone cells (~ 3 million of them ...
Physiology Practical
... The fibres of each optic tract synapse in the dorsal lateral geniculate nucleus, and from here, the geniculocalcarine fibre pass by the way of the optic radiation to the primary visual cortex in the calcarine area of the occipital ...
... The fibres of each optic tract synapse in the dorsal lateral geniculate nucleus, and from here, the geniculocalcarine fibre pass by the way of the optic radiation to the primary visual cortex in the calcarine area of the occipital ...
reptilian eyes and orbital structures
... both upper and lower eyelids are present. The borders of the upper and lower lids are often rich in secretory goblet cells.24 Most lizards have upper and lower eyelids, but most lack nictitating membranes. The lower lid of lizards contains a cartilaginous support, the tarsus. Lids are modified in a ...
... both upper and lower eyelids are present. The borders of the upper and lower lids are often rich in secretory goblet cells.24 Most lizards have upper and lower eyelids, but most lack nictitating membranes. The lower lid of lizards contains a cartilaginous support, the tarsus. Lids are modified in a ...
The Eye
... Contained within the orbits of the skull, the eyes are protected from injury by pads of fat. Factoid: The word “eye” has a long history, including Old English “ege” and Proto-Germanic “*augon.” Some cognates are Greek “okkos” and Latin “oculus,” both meaning “eye” or “sight.” ...
... Contained within the orbits of the skull, the eyes are protected from injury by pads of fat. Factoid: The word “eye” has a long history, including Old English “ege” and Proto-Germanic “*augon.” Some cognates are Greek “okkos” and Latin “oculus,” both meaning “eye” or “sight.” ...
The Visual Cortex
... Most cells are selective for a particular orientation and they require some movement. Orientation selectivity depends on the convergence of input from an appropriate subset of LGN relay cells as indicated above. Orientation selectivity may also be enhanced by cortical circuitry. The cell illustrated ...
... Most cells are selective for a particular orientation and they require some movement. Orientation selectivity depends on the convergence of input from an appropriate subset of LGN relay cells as indicated above. Orientation selectivity may also be enhanced by cortical circuitry. The cell illustrated ...
1 - contentextra
... increase postsynaptic transmission. For example, cocaine excites the postsynaptic neurones causing them to produce dopamine in the synapses of the brain. Dopamine stimulates the pleasure centre in the brain. This results in euphoria, talkativeness and, sometimes, violent behaviour. The inhibitory dr ...
... increase postsynaptic transmission. For example, cocaine excites the postsynaptic neurones causing them to produce dopamine in the synapses of the brain. Dopamine stimulates the pleasure centre in the brain. This results in euphoria, talkativeness and, sometimes, violent behaviour. The inhibitory dr ...
Text, Graphics, symbols, and codes
... • In normal or corrected vision persons, the light rays are exactly focused on the retina. • The retina consists of about 6 to 7 million cones concentrated near the center and about 130 million rods distributed in the outer areas of the retina around the sides of the eyeball. • The cones receive da ...
... • In normal or corrected vision persons, the light rays are exactly focused on the retina. • The retina consists of about 6 to 7 million cones concentrated near the center and about 130 million rods distributed in the outer areas of the retina around the sides of the eyeball. • The cones receive da ...
Text, Graphics, symbols, and codes
... • In normal or corrected vision persons, the light rays are exactly focused on the retina. • The retina consists of about 6 to 7 million cones concentrated near the center and about 130 million rods distributed in the outer areas of the retina around the sides of the eyeball. • The cones receive da ...
... • In normal or corrected vision persons, the light rays are exactly focused on the retina. • The retina consists of about 6 to 7 million cones concentrated near the center and about 130 million rods distributed in the outer areas of the retina around the sides of the eyeball. • The cones receive da ...
posterior vitreous detachment - Adelaide Eye and Retina Centre
... contract away from the retina, pulling the jelly free of the retina, leaving clear fluid behind – a ‘posterior vitreous detachment.’ The ‘floater’ frequently reported at this time is from the reorganisation of the fibrous elements, as well as occasionally some fragments from the retina that have bee ...
... contract away from the retina, pulling the jelly free of the retina, leaving clear fluid behind – a ‘posterior vitreous detachment.’ The ‘floater’ frequently reported at this time is from the reorganisation of the fibrous elements, as well as occasionally some fragments from the retina that have bee ...
What are the 5 Special Senses?
... a) lens can be _____________ b) rays bend __________…why is this important? c) image is_________ on retina…brain interprets as “right side up” Ciliary Body (smooth muscle), responsible for focusing lens d) Thin lens = _______________ vision e) Thick lens = ___________ciliary body contracts f) Near p ...
... a) lens can be _____________ b) rays bend __________…why is this important? c) image is_________ on retina…brain interprets as “right side up” Ciliary Body (smooth muscle), responsible for focusing lens d) Thin lens = _______________ vision e) Thick lens = ___________ciliary body contracts f) Near p ...
Vision in Dogs, Part One
... of the retina used for nearly all visual tasks. Dogs lack a true macula but do have a slightly greater concentration of cone photoreceptors centrally and in a horizontal band. In this “area centralis” cones still comprise only 10-20% of the photoreceptors. Yet, dogs may be better able to differenti ...
... of the retina used for nearly all visual tasks. Dogs lack a true macula but do have a slightly greater concentration of cone photoreceptors centrally and in a horizontal band. In this “area centralis” cones still comprise only 10-20% of the photoreceptors. Yet, dogs may be better able to differenti ...
Photoreceptor cell
A photoreceptor cell is a specialized type of neuron found in the retina that is capable of phototransduction. The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiation) into signals that can stimulate biological processes. To be more specific, photoreceptor proteins in the cell absorb photons, triggering a change in the cell's membrane potential.The two classic photoreceptor cells are rods and cones, each contributing information used by the visual system to form a representation of the visual world, sight. The rods are narrower than the cones and distributed differently across the retina, but the chemical process in each that supports phototransduction is similar. A third class of photoreceptor cells was discovered during the 1990s: the photosensitive ganglion cells. These cells do not contribute to sight directly, but are thought to support circadian rhythms and pupillary reflex.There are major functional differences between the rods and cones. Rods are extremely sensitive, and can be triggered by a single photon. At very low light levels, visual experience is based solely on the rod signal. This explains why colors cannot be seen at low light levels: only one type of photoreceptor cell is active.Cones require significantly brighter light (i.e., a larger numbers of photons) in order to produce a signal. In humans, there are three different types of cone cell, distinguished by their pattern of response to different wavelengths of light. Color experience is calculated from these three distinct signals, perhaps via an opponent process. The three types of cone cell respond (roughly) to light of short, medium, and long wavelengths. Note that, due to the principle of univariance, the firing of the cell depends upon only the number of photons absorbed. The different responses of the three types of cone cells are determined by the likelihoods that their respective photoreceptor proteins will absorb photons of different wavelengths. So, for example, an L cone cell contains a photoreceptor protein that more readily absorbs long wavelengths of light (i.e., more ""red""). Light of a shorter wavelength can also produce the same response, but it must be much brighter to do so.The human retina contains about 120 million rod cells and 6 million cone cells. The number and ratio of rods to cones varies among species, dependent on whether an animal is primarily diurnal or nocturnal. Certain owls, such as the tawny owl, have a tremendous number of rods in their retinae. In addition, there are about 2.4 million to 3 million ganglion cells in the human visual system, the axons of these cells form the 2 optic nerves, 1 to 2% of them photosensitive.The pineal and parapineal glands are photoreceptive in non-mammalian vertebrates, but not in mammals. Birds have photoactive cerebrospinal fluid (CSF)-contacting neurons within the paraventricular organ that respond to light in the absence of input from the eyes or neurotransmitters. Invertebrate photoreceptors in organisms such as insects and molluscs are different in both their morphological organization and their underlying biochemical pathways. Described here are human photoreceptors.