Module 10Hearing and Other Senses

Chapter 3, Pages 108-120Essentials of Understanding Psychology- Sixth Edition

PSY110 Psychology

© Richard Goldman

October 9, 2006

Ear

Converts sound waves into nerve pulses Senses motion Helps maintain balance

Ear Structure

Outer Ear Pinna Auditory canal Eardrum (Tympanic

membrane) Middle Ear Ossicles (bones)

Hammer Anvil Stirrup Eustachian tube

Inner Ear Oval window Cochlea

Basilar membrane Hair cells Auditory nerve Semicircular canals (3) – motion

sensors Otoliths- orientation & acceleration

sensors

Orientation &Acceleration

Otoliths

Sound Compression wave (not transverse) that travels through a

medium Human can hear sound in the range of 20-20,000 Hz (cycles

per second) – pitch Amplitude – Intensity of sound – measured in decibels (a

10X logarithmic scale) – sounds greater than 120db is painful Sensitivity –

Sound Waves

Sound Localization

Differences in intensity and time differences between sound reaching each ear help the brain determine what direction the sound came from

Theories of Hearing

Place Theory – Excitation of specific locations on the basilar is responsible for frequency discrimination

Frequency Theory – Excitation across the basilar membrane in sync with the sound is responsible for frequency discrimination

Hearing Loss

Damage due to: Physical damage – cotton swab (Q-tip) Illness – Mumps Prolonged exposure to loud sound Brief exposure to very loud sound

My be corrected with: Hearing aid – auditory discrimination is often a

problem Cochlear implant

Deaf Culture

Some people believe that belonging to a deaf culture is just a good as belonging to a hearing culture.

Olfaction - Sense of Smell

Humans can detect > 10,000 separate smells 1,000 different specialized types of olfactory

cells Pheromones – secreted odors use to

communicate

Gustation - Sense of Taste

Taste results from combinations of stimulating 4 different types of taste buds located on tongue, in mouth, and throat. Sweet Sour Salty Bitter

Humans have about 10,000 different taste buds

Each taste bud is replaced every 10 days

Interrelation of Taste and Smell The perception of taste often relies on the

perception of smell to identify a food substance

Skin Senses:

Touch Pressure Temperature Pain

Pain

Gate-control theory - Pain is a perception under control of the brain

Treatments: Medication Electro stimulation of the nerve Light Therapy Hypnosis Surgery Cognitive Restructuring - Rewrite of the pain

“script”