Describe cataracts and some of the technologies that can be used to prevent blindness from cataracts. Cataracts: A cataract is a clouding of the normally clear and transparent lens of the eye which results in decrease of vision. It is not a tumor, a new growth of skin or tissue over the eye, but a fogging of the lens itself. There are three types of cataract. They are:- a nuclear cataract- a cortical cataract- a scapular cataract A nuclear cataract is located in the nucleus – the centre of the lens.
The cause of this cataract is likely due o changes in the protein structure as we grow older. A cortical cataract develops from the outside of the lens extending over time to the centre. This cataract occurs often by people with diabetics. A scapular cataract begins at the back of the lens. People with diabetes, high far-sightedness, or those taking high doses of steroids have a higher risk of developing this form of cataract. Technologies: Technology can provide both temporary relief and a permanent resolution in regards to cataracts.
In the beginning stages of cataracts, the associated symptoms may be improved with new spectacles, anti-glare sunglasses or magnifying lenses. However, as the cataracts develop overtime, surgery becomes the most viable option in saving vision. The cataract surgery consists of the replacement of the cloudy lens with an artificial intraocular lens (OIL). Cataract surgery is usually only necessary when the patient’s vision loss interferes with everyday activities, such as driving, reading or watching TV. Discuss the implications of these technologies for society.
The implications for society of these technologies are that less people become necessarily blind, and have improved vision. It gives people more independence and improves their quality of life. In developing countries, cataract surgery carried out by groups such as the Fred Hollows Foundation has massive implications for these communities. Regaining sight in these countries increases an individual’s lifespan, and means that they can be more independent and active. Society can benefit from older people’s experiences and knowledge and can spend less time and money looking after those with cataract blindness.
Outline the role tot sound shadow cast by the head in the location tot sound. When sound waves are coming from directly in front, behind, or above the head both ears will hear the sound equally. When sound is coming from one side, the receptors in the ear closest to the sound will be stimulated slightly earlier and also more intensely. The brain then locates the sound as coming from one side of the body. The head is said to cast a sound shadow on the sound coming in to the ear from the opposite side of the head.
Sound shadow is created by absorbing high frequency mounds, which only the source of sound will activate the ear that is facing it. As the other ear behind it won’t be activated, which helps locate the direction of sound. Evaluate a hearing aid and a cochlear implant in terms: – the position and type of energy transfer occurring – conditions under which the technology will assist hearing – limitations of each technology. Explain using specific examples, the importance of correct interpretation of sensory signals by the brain for the coordination of animal behavior.
Signals from the environment such as light and sound are only meaningful if they an be interpreted correctly by the brain and used to bring about a coordinated response. The parts of the brain responsible for processing new information must work correctly to bring about the right interpretation. An example is us humans crossing a busy highway. Our behavior is coordinated as a result of correct interpretation of the signals coming into our brain and it is important for our survival. When we see a red light we know that we are meant to stop. When we see a green light we know that we are permitted to go.
The ear mould is located in the ear. Sound > electrical energy > louder sound > mechanical > electrochemical. The headset and microphone is positioned either behind the ear or Just above the ear. The transmitter coil is found behind the ear, on the head itself. The implant package is located inside the skull, opposite of the same place as transmitter coil. Sound > electrical > electrochemical. Conditions under which the technology will assist hearing Conductive hearing loss. SeCensoriouslyearing loss.
Used in children and adults who have residual hearing – not complete deaf, yet have some level of hearing. SeCensoriouslyearing loss. Used in children and adults who are complete deaf, either acquired or from birth. Limitations of each technology Cheap. Background noise amplified. Distance limited to approximate 3 memetersCan be used well at any age. Still requires lip reading. Damage to the auditory nerve can be problematic. No side effects. Expensive. Sounds are not natural. Have to learn new sounds. Surgery. Distance limited to approximate 1 5 memetersSide effects.