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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Psychology => Topic started by: shaiga95 on April 05, 2012, 11:03:06 pm
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Need help with this question
Q Name and describe one procedure used to study hemispheric specialisation in people with intact brains . Briefly describe the research findings from this method with a focus on what they demonstrate about hemispheric specialisation.
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--> The WADA Test
This test is used to show in which hemisphere the language centers of an individual are found. The patient is asked to raise both hands and count backwards from 100. Then either the left or right hemisphere of the patient would be anaesthetised. When the left hemisphere is anaesthetised, the right arm will fall and the patient will stop counting (because the language centers have been inactivated). When the right hemisphere is anaesthetised, the left arm will fall but the patient will continue counting. This basically shows that language production and interpretation is a specialist function of the left hemisphere, because it was not inhibited when the right hemisphere was inactivated.
--> The Tachistoscope
Basically just a screen that displays an image for a certain amount of time. When a verbal image is flashed in the left visual field, this will take longer to recognise than a verbal image flashed to the right visual field. This occurs because images flashed to the left visual field will be processed in the right visual cortex, and since this is a verbal image, the information must then be sent across the corpus callosum and into the left hemisphere for processing, which will take longer than a verbal image flashed to the right visual field, since this is then processed in the left visual cortex and is therefore already in the left hemisphere. This shows that language interpretation is a specialist function of the left hemisphere. However, the opposite is true for non-verbal images, since these are processed in the right hemisphere.
Simple stimuli such as colours and patterns are processed at the same speed.
--> Brain Imaging Techniques
The use of a functional brain imaging technique (eg. fMRI) can show the activity of certain brain areas during a task. When the task is verbal in nature, there'd be more activity in the left hemisphere, which shows that language is a specialist function of this hemisphere.