The brain :: essays research papers

Occipital, Frontal, and Temporal Lobes The occipital lobes are the center of our visual perception system. They are not particularly vulnerable to injury because of their location at the back of the brain, although any significant trauma to the brain could produce subtle changes to our visual-perceptual system, such as visual field defects and scotomas. The Peristriate region of the occipital lobe is involved in visuospatial processing, discrimination of movement and color discrimination (Westmoreland et al., 1994). Damage to one side of the occipital lobe causes homonomous loss of vision with exactly the same "field cut" in both eyes. Disorders of the occipital lobe can cause visual hallucinations and illusions. Visual hallucinations (visual images with no external stimuli) can be caused by lesions to the occipital region or temporal lobe seizures. Visual illusions (distorted perceptions) can take the form of objects appearing larger or smaller than they actually are, objects lacking color or objects having abn ormal coloring. Lesions in the parietal-temporal-occipital association area can cause word blindness with writing impairments (alexia and agraphia) (Kandel, Schwartz & Jessell, 1991). Frontal Lobe The Frontal Lobe is responsible for cognition and memory. The prefrontal area gives one the ability to concentrate, judgment and inhibition as well as personality and emotional traits. The premotor area is responsible for storage of voluntary activities and motor patterns. The motor area provides voluntary motor activity. Language is a motor speech. Temporal Lobe Location of the temporal lobe is near the temples just above the ear canal. Functions of the temporal lobe are to: Control hearing; from birth a baby can hear completely. The temporal lobe in the brain is fully developed before the baby is born. Language use; talking is very closely linked to hearing, and since people can hear they react by using language as means of communication. Emotions, especially fear plays a part in this role. Some complex aspects of vision, including the ability to see patterns such as faces. When the temporal lobe is damaged it causes:  · Deficits or limitations in understanding and comprehending spoken words  · May cause a lack of fear if the emotional responses are no longer working (a person seeing a snake may not be afraid because they don’t understand what the object even is)