Our sensory experience is usually divided into five distinct senses. However, certain sound and light frequencies cross these boundaries by stimulating multiple senses at once — especially touch. Infrasound and infrared are perfect examples of this multisensory interaction.
Infrasound: When Sound Becomes Tactile
Infrasound refers to low-frequency sound waves, typically below 20 Hz, which fall beneath the human hearing threshold. While our ears may not detect them, we can often feel these vibrations. At high intensities, infrasound can create sensations of pressure or vibration in parts of the body such as the chest or abdomen. Studies have shown that exposure to infrasound at levels between 120 and 150 dB can trigger physiological responses like fatigue, stress, or balance disorders.
Infrared: The Light That Warms
Infrared radiation is a form of light invisible to the human eye, with wavelengths longer than visible light. Although we can't see it, we can feel its effects as heat. Any object above absolute zero emits infrared, and this radiation is used in technologies like thermal imaging to measure temperature remotely. When infrared is absorbed by the skin, it releases thermal energy — explaining the warmth we feel near a source emitting this type of radiation.
A Fascinating Sensory Convergence
Infrasound and infrared show that our senses don’t always function in isolation. These phenomena prove that certain sound frequencies can simultaneously engage hearing and touch, enriching the way we perceive the world around us.
Have you ever experienced this kind of multisensory interaction in your daily life? Share your stories and thoughts in the comments below.
