MAVO Year 4 · Senses · Section 11.2
Ten human senses
Vision
The eyes contain the receptors for vision. Light reaching the retina changes receptor activity, and signals travel through the optic nerves towards the brain, where visual perception is constructed.
Hearing
The cochlea in each inner ear detects vibrations. Its sensory hair cells contribute to signals carried by the auditory nerve, allowing the brain to perceive sound.
Balance
The inner ear also contains vestibular organs. They detect head movements and its orientation relative to gravity, helping maintain balance together with vision and information from muscles and joints.
Touch
Receptors in the skin respond to light contact, movement or vibration. They help distinguish features such as smooth and rough surfaces.
Pressure
Other mechanoreceptors detect pressure and stretching of the skin. This information helps regulate grip, for example when holding a glass without dropping or crushing it.
Cold and warmth
Thermoreceptors respond to temperature and temperature change. Cold-sensitive receptors increase their activity during cooling within their operating range; warmth-sensitive receptors respond to warming. They do not simply switch at fixed universal boundaries of 37°C and 35°C. Extreme temperatures can activate pain pathways.
Pain
Nociceptors are sensory nerve endings responding to potentially damaging mechanical, chemical or temperature changes. Pain is the experience produced through nervous-system processing of such signals and other influences.
Smell
Olfactory receptors in specialised nasal lining respond to airborne chemicals after they dissolve in mucus. Their activity sends information towards the brain, producing smell perception.
Taste
Taste buds, found mainly on the tongue, contain cells responding to dissolved substances. Five basic taste qualities are sweet, sour, salty, bitter and umami. Flavour also depends strongly on smell, as well as texture and temperature.
The ten categories in this course are a useful school grouping; the body has additional sensory systems, such as those detecting limb position.
Glossary
- Pressure sense
- Detection of pressure and related mechanical changes by receptors in the skin and other tissues.
- Balance sense
- Detection of head movement and orientation by vestibular organs in the inner ear.
- Hearing
- Detection and perception of sound, beginning with sensory activity in the inner ear.
- Vision
- Detection and perception of light through the eyes and visual pathways.
- Cold sense
- Detection of cooling and relatively cool temperatures by thermoreceptors.
- Nociceptors
- Sensory nerve endings responding to potentially damaging stimuli.
- Smell
- Detection of odour chemicals by receptors in specialised nasal lining.
- Taste
- Detection of dissolved substances producing qualities such as sweet, salty, sour, bitter and umami.
- Touch sense
- Detection of light contact and other mechanical changes at the body surface.
- Warmth sense
- Detection of warming and relatively warm temperatures by thermoreceptors.