The cortical magnification means how many neurons in an area of the visual cortex are there as a function of visual field location to process the stimulus of a given size. Corresponding to the fovea of the retina, a very large number of neurons process information from a small region of the visual field…
The retina of our eye is composed of two types of cells: cones and rods. Cones are nerve cells sensitive to light, detail and color. Cones help us in reading letters and seeing objects especially at center. Cones are packed into the macula and help in visual details. On the other hand, rods are helpful for night vision and detection of moving objects. Rods provide peripheral vision and are insensitive to color. Thus, when we go to a dark place from light, we are unable to see objects clearly. There rods help us to distinguish objects, however, being insensitive to color, we are able to see only the colorless object.
Figure 1: Log polar mapping from retina (left) to straite cortex (right). Points near the center of the visual field are represented more heavily in cortex than are points in the periphery. Source: Schwartz (1994)
Retina is the part of eye which is composed of the layer of nerve tissue and it covers the back two-thirds of the eyeball. Retina receives the light and converts it into chemical energy which activates the nerves (cones and rods). These nerves conduct the messages out of the eye into the higher region of the brain. The retina thins out in the center of the macula forming a pit called fovea. The reason of its thinness is that the light passing through fovea is scattered or observed by this thinness before it reaches the photoreceptors.
Retinotopic Mapping: This is a standard pr...
Several of these areas are retinotopic, that is, their neurons respond to stimulation of limited receptive fields whose centers are organized to form a continuous mapping between the cortical surface and the visual field. The boundaries between most of the low order visual areas can be determined from their retinotopic properties: the local representation of the visual field on the cortical surface changes its orientation-the local visual field sign (VFS)-between adjacent visual areas.
Retina is located in the back of eye and has a complex structure. It is composed of macula which lies in the center of the retina and the macula covers up to inch diameter. The macula further contains a very small area called fovea. Fovea is responsible for very sharp vision (20/20). The fovea has the highest concentration of cone photoreceptors, ganglion cells, and horizontal cells rather than the rods. The reason for the high concentration of cones is that cones function best in the bright light. That is why fovea works best in daylight illumination. On the other hand, rods function better in dim light and are not capable of sharp vision. Thus, naturally there is high concentration of cones in the fovea in order to make it capable of sharp vision (20/20).
4. Comparison of Tactile with visual information
i). Tactile Information: When we touch something, the nerves present in the skin are stimulated and carry this information to the brain where it is interpreted and processed. Thus, the tactile information comes from touching objects which is carried through the nerves ending in the skin that convey sensations to the brain via nerve fibers. Feeling a leaf or ...
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“Final Exam Essay Sensation and Perception Example | Topics and Well Written Essays - 2750 Words”, n.d. https://studentshare.net/miscellaneous/275227-final-exam-essay-sensation-and-perception.
In this case, explanation of nature by the Presocratic, was based on four fundamental element, which include; earth, water, air and fire; in fact, these elements were compared to other extensive lists of basic elements (Wildman, 1). Nonetheless, this quest to explain nature by giving an account for these elements and focusing on object or processes involved in nature makes a significant contribution to knowledge; in fact, this can form a basis of understanding other elements that are studied in the present world.
This sensation is experienced by approximately 60-80% of all amputees with the majority experiencing phantom pain. Other than limbs, phantom pains and other sensations also occur for other amputated parts of the body. These may include the eyes, breasts, teeth etc.
These are eye, visual pathways and the visual centers of the brain. The function of eyes is to capture light and convert it into the neural messages. The visual pathways modify and transmit these messages from the eye to the brain where the messages are interpreted by the brain and thus the living being "see" the object.
Particular attention will be paid to the spelling and grammatical features of this writing. The assessment will involve the specific comments to be made to the writer of this text and an additional analysis of the writer's development pursuant to the checklist established by Harris et al (2003: 104).
You may choose to have all subjects observe the same room at different times or have the subjects each observe different rooms. After one minute, ask your subjects to close their eyes. Once their eyes are closed, ask them to recite
The colonialists were awarded the rights to control the appointments of clerics in these newly discovered regions. In fact, direct contact between the clerics and Vatican was prohibited, thereby giving states express authority over the church. This kind of control did not go