Learn how the central neural system works

This is in continuation to the last article focusing on neural system and mechanisms of neural coordination in a human body. Central neural system Forebrain • The cerebral cortex contains motor areas, sensory areas and large regions that are neither clearly sensory nor motor in function. • These regions, called the association areas, are responsible […]

This is in continuation to the last article focusing on neural system and mechanisms of neural coordination in a human body.

Central neural system
Forebrain
• The cerebral cortex contains motor areas, sensory areas and large regions that are neither clearly sensory nor motor in function.
• These regions, called the association areas, are responsible for complex functions like intersensory associations, memory and communication.
• Fibres of the tracts are covered with the myelin sheath, which constitute the inner part of cerebral hemisphere.
• They give an opaque white appearance to the layer and, hence, are called the white matter.
• The cerebrum wraps around a structure called thalamus, which is a major coordinating centre for sensory and motor signalling.
• Another very important part of the brain called hypothalamus lies at the base of the thalamus.
• The hypothalamus contains a number of centres which control body temperature, urge for eating and drinking.
• It also contains several groups of neurosecretory cells, which secrete hormones called hypothalamic hormones.
• The inner parts of cerebral hemispheres and a group of associated deep structures like amygdala, hippocampus, etc., form a complex structure called the limbic lobe or limbic system.
• Along with the hypothalamus, it is involved in the regulation of sexual behaviour, expression of emotional reactions (e.g., excitement, pleasure, rage and fear), and motivation.

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Midbrain

• The midbrain is located between the thalamus/hypothalamus of the forebrain and pons of the hindbrain.
• A canal called the cerebral aqueduct passes through the midbrain.
• The dorsal portion of the midbrain consists mainly of four round swellings (lobes) called corpora quadrigemina.

Hindbrain

• The hindbrain comprises pons, cerebellum and medulla (also called the medulla oblongata).
• Pons consists of fibre tracts that interconnect different regions of the brain.
• Cerebellum has very convoluted surface in order to provide the additional space for many more neurons.
• The medulla of the brain is connected to the spinal cord.
• The medulla contains centres which control respiration, cardiovascular reflexes and gastric secretions.
• Three major regions make up the brain stem – midbrain, pons and medulla oblongata.
• Brain stem forms the connections between the brain and spinal cord.

To be continued…
By Dr. Modala Mallesh
Subject Expert
Palem, Nakrekal, Nalgonda
9989535675