Brain, Cerebrum, Laterality
BACKGROUND The dominance of one cerebral hemisphere over the other helps a human brain to acquire laterality, which is defined as the ability to perform majority of day to day tasks more effectively with one hand of our body. The laterality is a measurable tool and various standardized questionnaires have been proposed to define the types of laterality in an individual. This is discussed in detail in the main text of the article. The predominant markers of laterality (handedness) are dependent on various internal and external factors, which include genetic social and cultural factors. The age, gender, social and cultural environment play a major role in defining as well as fixation of laterality. It is believed that lateralized behaviours are expressed in a very early stage of development. Functional lateralization occurs in the paired organs such as hands, legs, eyes and ears in relation to cerebral hemispheres. Intelligence may be defined as the ability of a person to react or respond to various problems for the survival in natural and social environment. In broad terms, it may be regarded as the capacity of reasoning, planning, and problem solving, thinking comprehension ideas and learning from experiences rather than just having a textual knowledge. Intelligence reflects broader capacity of developing ideas, senses, and provides appropriate thought pattern for various life situations. The individual difference in the levels of intelligence is imported with respect to life outcomes such as achievements in school, occupational benefit, social achievements, and job performances. Differences have been observed among left and right handers with regard to cognitive ability and levels of intelligence. Effects of intrauterine environments in defining laterality, how various neurological disorders are associated with it and future areas of research are discussed thoroughly in the article.
