Begin by reading this post: The Tortoise Model of Perception.
Your normal view of perception is sound is emitted, it moves toward your ears, and then it enters the ears, and then the brain, where it is recognized. This model of perception is not accepted in the Vedic scriptures. The senses are like the limbs of a tortoise. They are moving out, coming into contact with the sense objects, and by that contact, sense perception is created. The result is that if we control our senses, then we will not perceive the world. By sense control, we will only perceive what we want to perceive. Like I said in the earlier response, consciousness can be withdrawn from pain.
There are many equivalent descriptions of this process. In a simple sense, we can say that our consciousness “goes out” to attach to the world. In a more sophisticated sense, we can say that the senses are “going out” to attach to the world. And an even more sophisticated description is that the prana is moving. What Prabhupada calls “air” is prana. You have to see the prior sentence.
We can perceive the action of the air when the branches of a tree move or when dry leaves on the ground collect together. Similarly, it is only by the action of the air that a body moves, and when the air circulation is impeded, many diseases result.
The “action of the air” means that there is prana and it has an effect. The tree branches and leaves move as a result of this prana. Matter exists in a state of potentiality and it doesn’t move automatically. It is moved by prana, which acts in the control of Causal Time, guna, karma, and chitta. So, five agencies are responsible for the movement. Ultimately, guna, karma, chitta, and prana are present only if a soul is present. Hence, consciousness must always be present. Similarly, Causal Time is also consciousness. So, everything moves due to that consciousness.
When a sound is perceived, there is–(a) a channel of communication, and (b) information transacted on this channel. You can think of the client-server model of communication. The source of sound sends a request to the receiver: Do you want to listen? If the ear is eager, it accepts the request, and a connection is established, and sound is received. If the ear is withdrawn, that request is ignored, and then the sound doesn’t enter our ears, and then the sound is not heard.
Prabhupada states the same thing as follows: “If the air circulation is stifled, we cannot approach a place after hearing”. What is “after hearing”? It is received request: Do you want to hear? What is “approach a place”? It is the information received after connection establishment. This information exchange cannot occur “if the air is stifled”. Everything is very precisely presented.
All this seems hard because we are accustomed to think in terms of motion of matter. But in Vedic philosophy, matter doesn’t move. The consciousness moves from one place to another. So, when you hear an object, sound is not moving. Rather, the consciousness is moving to the sound. To make the consciousness move, there has to be an attract, a “request”. That request is not movement of matter but the movement of prana under the influence of another consciousness. In short, even that “request” is another consciousness interacting with our consciousness to create a connection. Thus, everything is easy if we know that matter is not moving; only the soul is moving.
You can think of a flood, cyclone, or storm. Many things are destroyed but some things are not. The things that are protected, are saved because the flood sends a request to each thing: Should I affect you? If there is bad karma, then it is automatically approved. But those who know how to control the prana or those who don’t have the bad karma decline this request. Then there is no effect.
All these things require a peaceful mind. Impatience will not produce any realization. You can read Time and Consciousness when you have time. It discusses this process in detail.