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longitudinal fissure. Its outer layer is called cerebral cortex and it contains gray matter. The inner part is composed of white matter and consists of axons or nerve fibres. It is in the cortex that the areas controlling voluntary movement, the senses, language and vision are found. Areas related to memory and thought are also housed in the cortex. Interestingly, the right hemisphere controls the left side of the body and vice versa. Large parts of cortex are yet to be understood, but various experiments have proved that logic, calculations and language are directed by the left hemisphere whereas, discipline, equanimity, calmness, patience and benevolence are guided by the right hemisphere. Mahapragya has used this fact in his technique of meditation. He has successfully projected the attention on right hemisphere for enhanced spiritual experiences.
The central brain lies between the upper cortex and bottom cerebellum. It is a monolithic section and is connected to the cortex with corpus callosum. It is here that the hypothalamus, pineal and pituitary glands are situated. This section is an important link to our physiological, mental and emotional well being.
The most interior part of the brain contains cerebellum, medulla and pons along with the brainstem. At the upper end of brainstem there are connections with the centres in the cerebellum concerned with consciousness. The lower end of brainstem, called medulla oblongata, is where sensory and motor nerve fibres of the spinal cord cross over.
1.2. Limbic System
In 1878, the French neurologist Paul Broca called attention to the fact that, on the medial surface of the mammalian brain, right underneath the cortex, there exits an area containing several nuclei of gray matter (neurons) which he denominated limbic lobe (from the Latin word 'limbus' that implies the idea of circle, ring, surrounding, etc) since it forms a kind of border around the brain stem.
Emotions and feelings, like wrath, fright, passion, love, hate, joy and sadness, are mammalian attributes, originated in the limbic system. This system is also responsible for some aspects of personal identity and for important functions related to memory. It consists of several subcortical structures located around the thalamus:
hippocampus: involved in the formation of long-term memory amygdala: involved in aggression and fear hypothalamus: controls the autonomic nervous system and regulates blood pressure, heart rate, hunger, thirst, sexual arousal and the
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