There are five main senses, and each consists of organs with specialized cellular structures that have precise functions and receptors for specific stimuli. All these organs contain cells that have links to the nervous system and hence to the brain. Sensing is concluded at primitive levels in the cells and integrated into sensations in the nervous system. The five senses are the sight (the most developed sense in humans), hearing (second most developed sense), taste, smell and touch. These allow people to interact at different levels with the world around them. To each of these senses corresponds a certain organ within the body, sight is connected to the eyes, hearing to the ears, taste to the mouth, smell to the nose, touch to the skin.

 

What are the five senses?

Sight is the sense responsible for the perception of visual stimuli. It allows us to identify shapes, reliefs, distances and color of what is being observed. The binocular vision (i.e. that carried out by both eyes at the same time) is that which allows the perception of three-dimensional objects within a space.

Hearing is the sense in charge to obtain the sounds coming outside and around the human body and to transmit them, through a complex mechanism that originates in the pavilion headset, and henceforth allowing for a certain area of the brain to receive them and decode them.

Taste is the way we provide information about what flavor certain foods we eat or drink have, allowing us to distinguish between, bitterness, sweetness, flavor and acidity. The structures that allow us to appreciate the flavor of what we introduce into the mouth of the sensory receptors are highly specialized: they are called glasses, buttons and taste buds, which are found on the tongue, palate, pharynx and larynx. Integration of the ‘primary’ tastes originate in more complex taste sensations.

The sense of smell is the main sense that allows for the perception of fragrant stimuli. The chemoreceptors are special cells that can react to the chemical characteristics of the odorous substances located in a particular area of the nasal mucosa, the olfactory mucosa. These neurons are highly specialized with a tuft of cilia and their bases are prolonged in the nerve fibers, through the ethmoid bone (the bone that forms the roof of the nasal cavity) reaching the olfactory bulbs, from here other neurons then reach the brain triggering the perception of certain odors.

Touch is the sense which enables us to recognize certain characteristics of physical objects that we come into contact with, such as hardness or shape. The transmission of the sense of touch from the outer surface of the body to the brain is made possible by the complex mechanisms that originate in highly specialized cells for this purpose, the receptors of touch.

 

What functions do the sense organs serve?

The sense organs are those organs (eyes, ears, mouth, nose and skin) which allow people to interact at different levels with the world around them. They have been essential for the survival of mankind, and have first been traditionally classified by Aristotle (384 BC – 322 BC)