The 8 Senses
The eight human senses consist of the five familiar external senses (sight, hearing, touch, taste, smell) and three "hidden" internal systems (vestibular, proprioception, and interoception). Together, these systems gather data from both the outside world and inside the body to help the brain navigate everyday life.
The 5 External Senses
Sight
Interprets light, colours, shapes, distance and movement through the eyes.
Hearing
Processes sound waves to distinguish volume, pitch, direction and tone.
Touch
Detects pressure, texture, temperature, vibration and pain via skin receptors.
Taste
Identifies chemical flavours through the tongue, categorising them into sweet, salty, sour, bitter and umami.
Smell
Processes chemical scents in the air via receptors inside the nose.
The 3 Hidden Internal Senses
These systems track movement, gravity and the physiological state of the body:
Vestibular (Balance & Movement)
Located in the inner ear, this sense tracks head position and motion. It governs coordination, balance and spatial orientation
Proprioception (Body Awareness):
Relies on receptors in muscles and joints to inform the brain of body position. It allows you to move your limbs accurately without looking at them.
Interoception (Internal Body Signals)
Monitors the organs to detect internal conditions like hunger, thirst, heart rate, fatigue and the need to use the toilet.
Not a sense, Yet...
Alexithymia (difficulty identifying and describing emotions)
Fundamentally linked to interoception—the brain's ability to perceive internal bodily signals like heart rate, breathing or stomach tension. Research suggests alexithymia is largely driven by an impaired ability to translate these physical sensations into emotional experiences.
