The five senses (smell, taste, sight, touch and hearing) are the mechanisms by which living beings know and relate to the outside world. The information from the environment enters through the senses and travels through the neurons until it reaches the brain, which is in charge of processing the data.
In the human being there are five senses:
- sense of smell. It is the ability of the body to capture and understand the different smells of the environment.
- Sense of taste. It is the ability of the body to perceive the taste of things (salty, sweet, bitter and acid).
- Eyesight. It is the body’s ability to capture electromagnetic waves of light and obtain information about the color or brightness of something.
- auditory sense. It is the body’s ability to process sound vibrations from the environment.
- Sense of touch. It is the body’s ability to determine the texture, shape and temperature of bodies.
The senses of the human being they are limited and, for this reason, they can be misleading. This is mainly due to a perception error (which is the interpretation that the brain makes of the stimuli perceived by the senses). The senses and perception can deceive the subject for internal or external reasons.
An example of how the senses deceive due to an external cause is the cinema, where the principle of the illusion of movement is used so that the human eye perceives movement and not the autonomous images that are projected in sequence.
An example of how the senses deceive due to an internal cause occurs with the consumption of substances, such as alcohol or drugs, which alter spatial perception.
Gestalt laws
Gestalt laws were established by Max Wertheimer, supporter of the German school of Gestalt psychology, and are 13 rules that explain the origin of perceptions (mainly visual).
These laws are:
- law of totality. The whole is the sum of the parts.
- structure law. A form is constituted as a whole regardless of the parts that form it.
- law of dialectics. Each subject decides if an element is figure or background.
- Law of contrast. A form is better perceived when the contrast between figure and background is greater.
- law of closure. A shape will be better the more closed its outline is.
- law of completion. The brain naturally tends to close contours that are not closed.
- notion of pregnancy. The subject tends to remain impregnated looking at a certain element.
- Topological invariance principle. A good shape is one that can be deformed by the person.
- Masking principle. Good shapes resist warping.
- Birkhoff’s principle. It deals with the importance of the axes in the forms.
- proximity principle. The brain tends to make groups with isolated elements that are close to each other.
- memory principle. Forms are better perceived if they are presented more than once.
- Nesting principle. The elements are better perceived if they are presented in a hierarchy.
Examples of how our senses deceive us
By external agents
- When a sequence of drawings is made and then the passage from one drawing to another is accelerated (these drawings being similar, but with some difference), the sensation that the image has movement is produced. This is the principle of cinematography.
- If an individual closes his eyes, covers his ears and touches a surface and feels the vibrations of something, he will not be able to perceive whether it is rhythmic music, a noise produced by a machine in operation or a stampede.
- When a pencil is placed in a glass of water, refraction causes the human eye to see a distorted image of the pencil, which appears to be broken.
- When a car is driving on a road and the ambient temperature is high, it is possible to glimpse a “mirage”, because water is seen on the road but, as the vehicle approaches that place, the water disappears.
- Optical illusions that deceive the eye and the brain are those in which a distorted color, shape or perspective of reality is perceived.
By internal agents
- High fever can produce an alteration of what is perceived by the senses.
- Drug use can generate some kind of hallucinations.
- Tobacco consumption can cause dizziness and alteration of the senses.
- Visual or auditory hallucinations occur when voices are heard or things are seen that do not exist in reality, this can be the product of certain diseases.
- The perception of a color or a texture is different for each individual because it depends on the visual and sensitive organ of each person.