Hearing & Touch

Audition

The sense or act of hearing and allows us to perceive sound waves

Frequency

The number of sound waves that pass a point in a given time and determines a sound's pitch

Pitch

A tone's experienced highness or lowness, which depends directly on the frequency of the sound wave

Outer ear

The visible external structure of the ear that channels sound waves into the auditory canal toward the eardrum and vibrates in response to sound

Middle ear

The chamber between the eardrum and cochlea has the eardrum and three tiny bones which are the hammer, anvil, and stirrup and function to transmit and concentrate the eardrum's sound vibrations onto the cochlea's oval window

Inner ear

The innermost part of the ear has the cochlea and the semicircular canals and turns sound vibrations into nerve signals using tiny hair cells and to control your balance

Cochlea

A coiled, bony, fluid-filled tube in the inner ear which sound waves trigger nerve impulses

Sensorineural hearing loss

Hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves, also known as nerve deafness

Conduction hearing loss

Hearing loss caused by damage to the mechanical system like the eardrum or the tiny bones of the middle ear that conducts sound waves to the cochlea

Cochlear implant

A device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Place theory

The brain detects pitch based on the exact spot where sound vibrates the cochlea's membrane and explains how we hear high-pitched sounds

Frequency theory

The brain detects pitch by matching the speed of nerve signals to a sound's frequency, which explains how we hear low-pitched sounds

Gate control theory

The idea that the spinal cord contains a neurological gate that either blocks pain signals or allows them to pass to the brain

Kinesthesia

The system for sensing the position and movement of individual body parts

Vestibular sense

Your brain's awareness of body movement, position, and balance, which is controlled by the semicircular canals and vestibular sacs in the inner ear

Sensory interaction

One sense may influence another, as when the smell of food influences its taste

Embodied cognition

The theory that your physical body, sensory experiences, and movement actively shape how you think, learn, and feel

Absolute Threshold

The weakest amount of sensory stimulation needed to detect a stimulus 50% of the time

Difference Threshold

The smallest amount that a stimulus must change for a noticeable difference

Top Down Processing

How your brain uses prior knowledge, memories, expectations, and context to interpret sensory information and and shape what you perceive

Bottom up processing

How your brain builds a perception from scratch using only incoming raw data from your senses

Signal Detection Theory

How we make decisions under conditions of uncertainty and specifically why different people respond differently to the exact same stimuli