To what extent is it true that people are either ‘left brained’ or ‘right brained’?
The term ‘left-brained’ or ‘right-brained’ is commonly used to refer to certain personality types. It is assumed that people who use the right side of their brains are more creative, thoughtful and subjective, while those who use the left side are more logical, detail-oriented and analytical (Novotney, 2013). In order to acknowledge these differences this essay will highlight what is meant by lateralisation of the brain and the specialisation of the human cerebral cortex. Equally as important, is to explain how handedness has developed and how it relates to cognitive functioning. Finally, by looking at how we study the brain and different research techniques used, a thorough analysis can be discussed.
The two hemispheres that make up the human brain are not mirror images as once thought; although similar it is believed they carry out very different functions. There are many crossed connections throughout the brain which leads to asymmetries between the hemispheres. In particular the left part of the primary motor cortex controls most of the movement on the right side of the body (Comer, Gould & Furnham, 2013). Communication occurs between the two hemispheres via the cerebral cortex. This is the layer of cells on the outer surface of the hemispheres known as grey matter (Kalat, 1995). The cerebral cortex is responsible for the communication between both hemispheres in the form of large groups of axons, known as the corpus callosum, the anterior commissure, the posterior commissure and the hippocampal commissure (Barnes, 2013).
The corpus callosum is a collection of myelin coated axons that connects the two hemispheres together. People who have undergone surgery to sever the corpus callosum to reduce the amount of epileptic seizures they have are referred to as ‘split-brain patients’ (Comer, Gold & Furnham, 2013). The differences between the two hemispheres of the brain are
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