No understanding of aesthetics would be complete without a little knowledge of sensation and perception. The process of sensation starts off when stimulus enliven our nervous system. Facial clients / patients experience five sensations – two of which are auditory and smell and, three skin senses – touch, temperature and pain. The general characteristics of sensation are absolute (minimum) thresholds and difference (minimum amount of difference between two stimuli) thresholds.
Perception on the other hand, is defined as a process by which the brain chooses and forms, coordinates and arranges its interpretation of sensations. Our perceptual abilities are our most important link to the outside world. Each kind of sense organ is dedicated to receiving a specific type or particular quality of stimulus. It is through our senses that we take in information about the environment.
Out of all the senses we rely on, it is our sense of vision, more than anything else that we use to survive and comprehend the world. The physical stimulus that the eye responds to is light. It is made up of electromagnetic energy. The physical characteristics of light are wavelengths contained in a color spectrum which we interpret through mental vibrations (psychological sensations). It is these neural impulses that relay messages to the brain when light is experienced through the retina of the eye. It is the rods and cones (specialized nerve cells) that react.
Our olfactory system is designed to act in response to chemicals that are in the air. Smell occurs when airborne molecules travel up our nose. It is our way of detecting danger and of experiencing pleasure. Our sense of smell is mainly a warning signal.
The sensation of touch varies over portions of our bodies. Only one specific receptor (pacinian corpuscle) for touch has been found. They are called dendrites (branched extension of nerve cells) and they respond to touch.
The skin reacts to heat and cold. The number of regions sensitive to cold far outweigh those sensitive to heat. We experience the sensation of heat when both warm and cold receptors are stimulated simultaneously.
Pain sensations are caused by a variety of stimuli including extreme pressure and heat. In an aesthetic practice the sensation of pain is usually caused by the force of extracting comedos. A well-known explanation is the “pain gating” theory which suggests that there is an actual neural gate that can be opened or closed by the form a neural message takes.
Understanding the brain and body responses is paramount and the physiology behind sensations and perceptions can make a big difference when applying this information to the practical aspects of aesthetic treatment delivery. I personally find it all very fascinating and if you do too there is more to read and view on this and other related topics – see below…
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