The lateralization of brain function refers to how some functions, or cognitive processes tend be more dominant in one hemisphere than the other (Sperry, 1968). The medial longitudinal fissure splits the human brain into two distinct cerebral hemispheres, joined by the corpus callosum (Gray, 1985). The two hemispheres demonstrate strong, but not comprehensive, bilateral symmetry in both structure and performance. Handedness is not a single variable, but can be placed in a spectrum of 4 separate categories; left-handedness, right-handedness, mixed-handedness, and ambidexterity (Annette, 2002). However, handedness for simplicity can be defined as the hand that performs faster or specifically on physical tasks (Broca, 1979). Broca suggested that
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It was thought that a preference in the left hand would lead to a variety of psychiatric and psychological problems, such as epilepsy (Rasmussen and Milner, 1977) and schizophrenia (Crow, 1997). However, there has been no clear understanding of the relationship between linguistic capacities, cerebral asymmetry, handedness, and psychiatric disorders (Klar, 1999). It was also argued that cultural influenced determined a person’s hand preference (Rife, 1940). A study conducted by Kanski (2006) tested right and left handers reaction time on simple reaction tests. This study was to examine the difference of cross-lateralization reaction times between left-handed and right-handed individuals in an effort to clarify whether the corpus callosum is more developed in left-handed individuals. This experiment used 3 left hand and 3 right hand subjects, and measured their response to touch stimuli on each finger. Overall the results showed that left handers had a faster reaction time than right handers. However, this experiment relied on a stopwatch timing, and did not account for human error. In another similar reaction experiment conducted using a computer mouse, right-handed people were faster with their right hand, but left-handed people were equally fast with both hands. However, the reaction time advantage of the preferred over the non-preferred hands was very small (Peters et al,
It was thought that a preference in the left hand would lead to a variety of psychiatric and psychological problems, such as epilepsy (Rasmussen and Milner, 1977) and schizophrenia (Crow, 1997). However, there has been no clear understanding of the relationship between linguistic capacities, cerebral asymmetry, handedness, and psychiatric disorders (Klar, 1999). It was also argued that cultural influenced determined a person’s hand preference (Rife, 1940). A study conducted by Kanski (2006) tested right and left handers reaction time on simple reaction tests. This study was to examine the difference of cross-lateralization reaction times between left-handed and right-handed individuals in an effort to clarify whether the corpus callosum is more developed in left-handed individuals. This experiment used 3 left hand and 3 right hand subjects, and measured their response to touch stimuli on each finger. Overall the results showed that left handers had a faster reaction time than right handers. However, this experiment relied on a stopwatch timing, and did not account for human error. In another similar reaction experiment conducted using a computer mouse, right-handed people were faster with their right hand, but left-handed people were equally fast with both hands. However, the reaction time advantage of the preferred over the non-preferred hands was very small (Peters et al,