Indriyas or the senses of the individual body are defined as delicately tuned receptors and they are in fact the highly accurate transmitters of information to and from the body and environment.

In Ayurveda, Indriyas or the five senses of human life are defined as the third major component of life. The five senses or the indriyas act as the bridge between the non-physical parts of life that are the atma or the soul and the manas or mind on one side and the environments and the physical body on the other side. Ayurveda defines that the internal reality would be absolutely disconnected from the external reality without the five senses.

It is said that the indriyas collect information from the outer world. These incoming perceptions get relayed to the manas or mind in the form of touch, sound, colour, taste and smell, which are the five senses of human body. If the gathered perceptual information collected by the five senses of human body is of proper quality and quantity then it will have an inspiring and supporting influence on the mind. And if the quantity and the quality is not in proper balance, then it will create imbalance in the mind and ultimately in the entire system and body.

Ayurveda is considered as the oldest existing health care system of the world. Ayurveda offers complete health and fulfilment to every man and woman on earth. However, it needs to be noted that Ayurveda is not just a medicinal approach to health. This natural science gives a proper understanding of the non-material components of life.

Indriya, one of the main principles of Ayurveda contribute to the wholeness of experience of life. In Ayurveda, the stage after loss of knowingness is called the `pragya aparadha` and it defines that the primary cause of any disease is the improper use of all the senses with the materialistic objects. Misuse of the senses can occur in three different ways. The three different ways are as follows -

Firstly, taking in excessive sensory stimuli, which can occur by listening to excessive loud music, watching too much of television, talking too much or living in a noisy environment.

Secondly, insufficient sensory input constitutes the second way to misuse the senses and comprise all such situations where there is a deficit of sensory perception. The syndrome, which is called the `Seasonal Affect Disorder`, occurs due to extreme northern climates especially during the winter months when there is less sunlight. It causes affective disorders like depression.

Thirdly, sensory intake that is emotionally or morally repugnant represents the third misuse of the senses. It states that hearing or seeing things which are distressing can disrupt the balance between the body and mind. Misuse not only impairs the senses themselves but also directly harms the mind and damages the body by weakening the coordination between body and mind.

Difference between Organ of Senses and Senses
In order to understand the functioning of the indriyas or the five senses, making a distinction between the organs of perception and the senses is considered important. The indriyas, unlike the physical sense organs have no material reality and they are subjective and subtle processes. This process of perception constitutes a movement from the concrete to abstract and from the gross to the subtle. The eye or the organ of sight is able to perceive because there is the sense of sight functioning through it. However, the sense of sight does not require any physical organ in order to function. It is believed that when a sense organ stops functioning properly, it is not the sense that is lost but it is the usual vehicle of that sense that is lost, which was the mode of connection to the outer world. This fact is applicable in case of all the five organs and their respective senses or indriyas. Each sense or indriya and its corresponding organ of perception are highly specialized. Each of them perform a function which neither other sense organ nor any body part can do. For instance, it is only the eye that can see and it is the ear that can hear.

Nature of Indriyas
The main function of the senses is to carry information from the outside world to the inside. When a person eats incorrectly, he/she gets indigestion and the senses bring information regarding the indigestive distress to the attention of the mind. It is the mind that ultimately decides not to eat again unless and until the stomach settles down completely. Proper functioning of the indriyas or the five senses is very important and crucial for the maintenance of good health. There is an inherent intelligence within each single sense which protects the mind and the body from any sort of improper sensory impressions. The senses, when used correctly, connected and alert, are considered as essential to the process of making choices that create and maintain health. Physical disease can impact the sensory perception by compromising the operation of the sense organs.

Indriyas or the five senses are the links between the outer world and the human body. Ayurveda sees this vital and integrated connection of functioning of the body as the main basis of good health and happiness.