Optically induced anisometropia in kittens.
... study,26 but probably due to protocol differences (e.g., lower stimulus contrasts and luminances) they are lower than the visual acuities reported by Mitchell et al.23> 24 for normal age-matched kittens. The grating acuities determined for the untreated eyes of the anisometropic kittens were not sig ...
... study,26 but probably due to protocol differences (e.g., lower stimulus contrasts and luminances) they are lower than the visual acuities reported by Mitchell et al.23> 24 for normal age-matched kittens. The grating acuities determined for the untreated eyes of the anisometropic kittens were not sig ...
Receptor Elements in the Thoracic Muscles of Homarus vulgaris and
... The mass of the dorsal thoracico-abdominal muscles is composed of three muscle units for which the terms first, second, and third dorsal thoracicoabdominal muscle are proposed. They all have their posterior attachments at the front edge of the 1st abdominal segment, the first muscle partly overlying ...
... The mass of the dorsal thoracico-abdominal muscles is composed of three muscle units for which the terms first, second, and third dorsal thoracicoabdominal muscle are proposed. They all have their posterior attachments at the front edge of the 1st abdominal segment, the first muscle partly overlying ...
Binocular Vision and Space Perception
... can be shown by using inadequate stimuli. If the retina is stimulated mechanically (pressure) or electrically, the resulting sensation is localized in the same specific direction in which it would be localized if the retinal elements had been stimulated by light. For instance, if we apply finger pre ...
... can be shown by using inadequate stimuli. If the retina is stimulated mechanically (pressure) or electrically, the resulting sensation is localized in the same specific direction in which it would be localized if the retinal elements had been stimulated by light. For instance, if we apply finger pre ...
1. Distichiasis is: Misdirected eyelashes Accessory row of eyelashes
... the prophylactic treatment for other eye is: a. Peripheral iridotomy b. Schele's operation c. Anterior sclerotomy d. Iridenclesisis 115. You have been referred a case of open angle glaucoma. Which of the following would be an important point in diagnosing the case? a. Shallow anterior chamber b. Opt ...
... the prophylactic treatment for other eye is: a. Peripheral iridotomy b. Schele's operation c. Anterior sclerotomy d. Iridenclesisis 115. You have been referred a case of open angle glaucoma. Which of the following would be an important point in diagnosing the case? a. Shallow anterior chamber b. Opt ...
Choroidal Thickness Study Using Swept-source
... SD-OCT images are highest in resolution near the zero-delay line. Thus, when the image is inverted, even if some resolution is lost at the vitreous and the retina, the resolution at the choroid is excellent. Swept-source (SS) OCT (DRI-OCT, Topcon) is a completely new technology that enhances the vis ...
... SD-OCT images are highest in resolution near the zero-delay line. Thus, when the image is inverted, even if some resolution is lost at the vitreous and the retina, the resolution at the choroid is excellent. Swept-source (SS) OCT (DRI-OCT, Topcon) is a completely new technology that enhances the vis ...
Choroidal Thickness Study Using Swept
... SD-OCT images are highest in resolution near the zero-delay line. Thus, when the image is inverted, even if some resolution is lost at the vitreous and the retina, the resolution at the choroid is excellent. Swept-source (SS) OCT (DRI-OCT, Topcon) is a completely new technology that enhances the vis ...
... SD-OCT images are highest in resolution near the zero-delay line. Thus, when the image is inverted, even if some resolution is lost at the vitreous and the retina, the resolution at the choroid is excellent. Swept-source (SS) OCT (DRI-OCT, Topcon) is a completely new technology that enhances the vis ...
eye training letter - VFW Department of Illinois Service Office
... 2. Diplopia extending beyond more than one quadrant or range of degrees When the affected field with diplopia extends beyond more than one quadrant or range of degrees, diplopia will still be evaluated based on the quadrant and degree range that provides the higher (or highest) evaluation. 3. Diplop ...
... 2. Diplopia extending beyond more than one quadrant or range of degrees When the affected field with diplopia extends beyond more than one quadrant or range of degrees, diplopia will still be evaluated based on the quadrant and degree range that provides the higher (or highest) evaluation. 3. Diplop ...
The Seventh Cranial Nerve HO
... Tumors within the petrous temporal may affect the facial nerve at the site of the geniculate ganglion. This leads to all the symptoms just described, plus loss of tearing on the affected side. Lesions of the facial nerve between the brain and the facial canal may affect one root and not the other b ...
... Tumors within the petrous temporal may affect the facial nerve at the site of the geniculate ganglion. This leads to all the symptoms just described, plus loss of tearing on the affected side. Lesions of the facial nerve between the brain and the facial canal may affect one root and not the other b ...
Breakdown of the Inner and Outer Blood Retinal Barrier in
... permeability of the blood-retinal barrier (BRB) to fluorescein in control and in 8 days streptozotocininduced diabetic rats. Vitreous fluorophotometry showed that fluorescein permeates BRB in control and in diabetic rats. However, in diabetic rats the permeability to fluorescein was significantly in ...
... permeability of the blood-retinal barrier (BRB) to fluorescein in control and in 8 days streptozotocininduced diabetic rats. Vitreous fluorophotometry showed that fluorescein permeates BRB in control and in diabetic rats. However, in diabetic rats the permeability to fluorescein was significantly in ...
THE LACRIMATION REFLEX
... A (the nucleus of the solitary tract) but those subserving taste may end in B (the so called " gustatory nucleus "). The preganglionic fibres to the salivary glands come from C (the -superior salivary nucleus). Those for the lacrimal gland may come from this nucleus, but some believe that they arise ...
... A (the nucleus of the solitary tract) but those subserving taste may end in B (the so called " gustatory nucleus "). The preganglionic fibres to the salivary glands come from C (the -superior salivary nucleus). Those for the lacrimal gland may come from this nucleus, but some believe that they arise ...
No. 32
... They arise from receptor cells in the nasal mucosa. Processes of these receptor cells pass through the perforations of the cribriform plate of the ethmoid bone and enter the olfactory bulbs of the telencephalon portion of the brain. In the olfactory bulbs, the nerve fibers synapse with neurons that ...
... They arise from receptor cells in the nasal mucosa. Processes of these receptor cells pass through the perforations of the cribriform plate of the ethmoid bone and enter the olfactory bulbs of the telencephalon portion of the brain. In the olfactory bulbs, the nerve fibers synapse with neurons that ...
Congenital Nasolacrimal Duct Obstruction
... them. At the zero point in the middle and at each points of intersection of the 15 degree and 30 degree lines there was a red dot. The red dots formed an inner square of eight dots and an outer square of sixteen dots. A pointer or indicator was a junction of three green cords knotted to form Y. The ...
... them. At the zero point in the middle and at each points of intersection of the 15 degree and 30 degree lines there was a red dot. The red dots formed an inner square of eight dots and an outer square of sixteen dots. A pointer or indicator was a junction of three green cords knotted to form Y. The ...
Ideal Observer Analysis
... organism’s photoreceptors are to the optimum for the given task (Regan et al. 2001). Alternatively, the free parameters might represent the receptive field shapes (the configuration of weights placed on each receptor) for some given number of postreceptor neurons. This would be a precise way of dete ...
... organism’s photoreceptors are to the optimum for the given task (Regan et al. 2001). Alternatively, the free parameters might represent the receptive field shapes (the configuration of weights placed on each receptor) for some given number of postreceptor neurons. This would be a precise way of dete ...
TEGMENTAL AFFERENTS OF THE AMYGDALOID BODY IN THE
... dorsal nucleus. Labeled cells were found in locus coeruleus, in both rostral and caudal part of dorsal raphe nucleus, and in the ventral tegmental area; in the latter the labeled cells were found on frontal cross-sections through the posterior segment of mammillary bodies. Single cells were seen in ...
... dorsal nucleus. Labeled cells were found in locus coeruleus, in both rostral and caudal part of dorsal raphe nucleus, and in the ventral tegmental area; in the latter the labeled cells were found on frontal cross-sections through the posterior segment of mammillary bodies. Single cells were seen in ...
Facial Nerve
... Millard gubler syndrome (6th palsy with contralateral hemiplegia)), Infections, Idiopathic Neuropathophysiological basis facial nerve disorders : Seddon classification (Neuropraxia (partial block of axoplasmic flow), Axonotmesis, Neurotmesis) in Axonotmesis axon sectioned so complete block of flow, ...
... Millard gubler syndrome (6th palsy with contralateral hemiplegia)), Infections, Idiopathic Neuropathophysiological basis facial nerve disorders : Seddon classification (Neuropraxia (partial block of axoplasmic flow), Axonotmesis, Neurotmesis) in Axonotmesis axon sectioned so complete block of flow, ...
theory for the development of neuron selectivity: orientation
... The various factors that influence synaptic modification may be divided broadly into two classes-those dependent on global and those dependent on local information. Global information in the form of chemical or electrical signaling presumably influences in the same way most (or all) modifiable junct ...
... The various factors that influence synaptic modification may be divided broadly into two classes-those dependent on global and those dependent on local information. Global information in the form of chemical or electrical signaling presumably influences in the same way most (or all) modifiable junct ...
- Ingineeri.com
... The Fast Optic Disc scan The optic cup profile can be evaluated by capturing a "Fast Optic Disc" scan The patient fixes on the target, which is automatically placed at the edge of the scan window so that the optic nerve is viewed toward the center of the video window. The operator then moves the sc ...
... The Fast Optic Disc scan The optic cup profile can be evaluated by capturing a "Fast Optic Disc" scan The patient fixes on the target, which is automatically placed at the edge of the scan window so that the optic nerve is viewed toward the center of the video window. The operator then moves the sc ...
one vision2012 - University of Illinois College of Medicine at Chicago
... start the visual process. However, other retinal cell types, while not normally photosensitive, often remain healthy. “We asked ourselves, ‘Could we make healthy retinal cells responsive to light and bypass dead photoreceptor cells?’” says David Pepperberg, PhD, SearlsSchenk Professor of Ophthalmolo ...
... start the visual process. However, other retinal cell types, while not normally photosensitive, often remain healthy. “We asked ourselves, ‘Could we make healthy retinal cells responsive to light and bypass dead photoreceptor cells?’” says David Pepperberg, PhD, SearlsSchenk Professor of Ophthalmolo ...
Lacrimal glands
... 3. Inner layer of the eyeball • Retina – 3-1. Nonvisual part – covers internal surface of ciliary body and iris Junction – irregular ora serrata 3-2. Optic part – sensitive to light 3-2-1. Pigmented layer – outer layer, attaches to choroids 3-2-2. Neural layer – attaches to pigmented layer around o ...
... 3. Inner layer of the eyeball • Retina – 3-1. Nonvisual part – covers internal surface of ciliary body and iris Junction – irregular ora serrata 3-2. Optic part – sensitive to light 3-2-1. Pigmented layer – outer layer, attaches to choroids 3-2-2. Neural layer – attaches to pigmented layer around o ...
Ophthalmology and Eye Disease - Faculty of Medical and Health
... electrical signal. Rods and cones Rods and cones process the visual signal in characteristic ways and are described by performance functions which include the rod and cone spectral sensitivity curves as well as light and dark adaptation curves among other measures. They also differ in the minimum de ...
... electrical signal. Rods and cones Rods and cones process the visual signal in characteristic ways and are described by performance functions which include the rod and cone spectral sensitivity curves as well as light and dark adaptation curves among other measures. They also differ in the minimum de ...
Eyes - LWW.com
... smooth. Their purpose is to protect the eye from foreign bodies and limit the amount of light entering the eye. In addition, they serve to distribute tears that lubricate the surface of the eye (Fig. 15-1). The upper eyelid is larger, more mobile, and contains tarsal plates made up of connective tis ...
... smooth. Their purpose is to protect the eye from foreign bodies and limit the amount of light entering the eye. In addition, they serve to distribute tears that lubricate the surface of the eye (Fig. 15-1). The upper eyelid is larger, more mobile, and contains tarsal plates made up of connective tis ...
Pathology of the facial nerve: A pictorial review
... and neck can be divided into glomus tympanicum, jugulare, vagale and carotid body tumour. Facial nerve paralysis is a rare symptom/complication of glomus tympanicum (5%). More common presentations are pulsatile tinnitus and conductive hearing loss. Imaging features: Glomus tympanicum appears as an e ...
... and neck can be divided into glomus tympanicum, jugulare, vagale and carotid body tumour. Facial nerve paralysis is a rare symptom/complication of glomus tympanicum (5%). More common presentations are pulsatile tinnitus and conductive hearing loss. Imaging features: Glomus tympanicum appears as an e ...
Visian ICL Product Information Visian ICL™ (Implantable Collamer
... the 4.9 mm group compared to 0% with the 5.8 mm. Night driving difficulties were absent/mild in71.1% of eyes using the 4.9 mm, 83.8% with the 5.2 mm, 85.4% with the 5.5 mm, and 91.9% with the 5.8 mm. A similar trend between the subjective symptom and the 36-month follow-up shows a negative correlati ...
... the 4.9 mm group compared to 0% with the 5.8 mm. Night driving difficulties were absent/mild in71.1% of eyes using the 4.9 mm, 83.8% with the 5.2 mm, 85.4% with the 5.5 mm, and 91.9% with the 5.8 mm. A similar trend between the subjective symptom and the 36-month follow-up shows a negative correlati ...
Trigeminal V, Abducent VI, Facial VII and Vestibulocochlear VIII
... middle and oral region of spindle tract of trigeminal nerve V nucleus in Camel is location and cell type is resemble that studying in other animal (10), Cat (5) . 2. Abducent nerve VI nucleus : The location and cells contain this nucleus in Camel is similar in Pig , Rabbit, Dog, Guinea Pig (9), (10) ...
... middle and oral region of spindle tract of trigeminal nerve V nucleus in Camel is location and cell type is resemble that studying in other animal (10), Cat (5) . 2. Abducent nerve VI nucleus : The location and cells contain this nucleus in Camel is similar in Pig , Rabbit, Dog, Guinea Pig (9), (10) ...
Chapter 144: Vestibular System
... head movements contain both types of acceleration, and the vestibular reflexes act in combination to maintain equilibrium. A third role of vestibular reflex activity is to help maintain muscular tone, a role in which both maculae and cristae participate. The labyrinthine contribution to skeletal-mus ...
... head movements contain both types of acceleration, and the vestibular reflexes act in combination to maintain equilibrium. A third role of vestibular reflex activity is to help maintain muscular tone, a role in which both maculae and cristae participate. The labyrinthine contribution to skeletal-mus ...
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.