1. THE AUDITORY SYSTEM
SENSE OF HEARING

2. THE AUDITORY SYSTEM
Mechanoreception: detection of vibration, perceived as hearing
Stimulus: sound waves
Sense organ: ears
Function: hearing
Auditory transduction: transforms sound waves into electrochemical impulses that the brain can interpret

3. SOUND WAVE PROPERTIES Sound has 3 characteristics:
Wavelength: frequency (determines pitch)
longer = lower frequency = lower pitch
shorter = higher frequency = higher pitch
measured in hertz = Hz
Wave amplitude: intensity (determines loudness)
shorter = less intensity = quieter
taller= more intensity = louder
measured in decibels = dB
roughly every 10 dB doubles loudness
Purity: quality (determines timbre/tone saturation)
uniqueness of sound

5. PARTS OF THE EAR Outer ear – air conduction Pinna Auditory canal
Middle ear – bone conduction
Eardrum (tympanic membrane)
Ossicles
Hammer (malleus), anvil (incus), stirrup (stapes)
Inner ear – fluid conduction
Oval window
Cochlea
Basilar membrane and hair cells
Semicircular canals
Vestibular sacs
Auditory nerve

7. PITCH PERCEPTION Place Theory Frequency Theory
States that each frequency produces vibrations at a particular spot on the basilar membrane.
Location
Explains high pitched sounds
States that the perception of a sound's frequency depends on how often the auditory nerve fires.
Neural impulses
Explains low pitched sounds

8. VOLLEY PRINCIPLE
Modification of frequency theory stating that a cluster of nerve cells can fire neural impulses in rapid succession, producing a volley of impulses.
Fixes limitations of frequency theory

9. AUDITORY LOCALIZATION
We have two ears
Sounds may reach one ear faster than the other ear
Or sounds may be louder in one ear than another
This let’s us locate the sound
Our head acts as a “shadow”
Sound shadow
Can not localize if directly in front, back or above

10. Conductive Hearing Loss Sensorineural Hearing Loss
Hearing loss occurs when sound is not conducted efficiently through the outer ear canal to the eardrum and the tiny bones (ossicles) of the middle ear.
Usually involves a reduction in sound level or the ability to hear faint sounds.
Can often be corrected medically or surgically
Caused by damage to the parts of the ear that connect to the cochlea
hearing loss occurs when there is damage to the inner ear (cochlea), or to the nerve pathways from the inner ear to the brain.
Most of the time, cannot be medically or surgically corrected.
most common type of permanent hearing loss. 
reduces the ability to hear faint sounds.
Caused by damage to the cochlea or to the auditory nerve
Mixed Hearing Loss

11. HEARING LOSS

12. THE TACTILE SYSTEM
SENSE OF TOUCH

13. THE TACTILE SYSTEM
Mechanoreception: detection of pressure, perceived as touch
Thermoreception: detection of temperature; perceived as warm and cold
Nociceptors: detection of noxious stimuli; perceived as pain
Stimulus: mechanical, thermal, and chemical energy
Sense organ: skin
Function: touching
Tactile transduction: transforms mechanical, thermal, and chemical energy on the skin into electrochemical impulses that the brain can interpret

14. THE SENSORY SYSTEM Three kinds of receptors: touch temperature warm
cold
pain
Four distinct skin senses:
pressure
warmth
Extreme heat & extreme cold are THE SAME!

15. PAIN Pain tells the body that something has gone wrong.
Congenital Insensitivity to Pain (CIP): A rare disease in which the afflicted person feels no pain.
no sense of smell
unable to sweat
sodium channel mutation

16. PAIN PATHWAYS Two pain pathways: fast A-delta fibers
less than 1 second
myelinated
slow
C fibers
a couple of seconds
unmyelinated

17. PAIN PERCEPTION Gate Control Theory: creates neural blockage
Studied by Ronald Melzack & Patricia Wall (1965)

18. ENDORPHINS
Neurotransmitters
natural opiate
morphine-like painkillers

19. THE GUSTATORY SYSTEM
SENSE OF TASTE

20. THE GUSTATORY SYSTEM
Chemoreception: detection of chemical stimuli, perceived as taste
Stimulus: soluble chemicals
Sense organ: tongue
Function: tasting
Gustatory transduction: transforms soluble chemicals in food into electrochemical impulses that the brain can interpret

21. THE OLFACTORY SYSTEM
SENSE OF SMELL

22. THE OLFACTORY SYSTEM
Chemoreception: detection of chemical stimuli, perceived as smell
Stimulus: volatile chemicals
Sense organ: nose
Function: smelling
Olfactory transduction: transforms volatile chemicals in the air into electrochemical impulses that the brain can interpret

23. THE KINESTHETIC SYSTEM
SENSE OF POSITION & MOVEMENT

24. THE KINESTHETIC SYSTEM
Mechanoreception: detection of vibration, perceived as hearing
Stimulus: sound waves
Sense organ: ears
Function: hearing
Auditory transduction: transforms sound waves into electrochemical impulses that the brain can interpret

25. SENSE OF BALABNCE & MOVEMENT
THE VESTIBULAR SYSTEM
SENSE OF BALABNCE & MOVEMENT

26. THE VESTIBULAR SYSTEM
Mechanoreception: detection of vibration, perceived as hearing
Stimulus: sound waves
Sense organ: ears
Function: hearing
Auditory transduction: transforms sound waves into electrochemical impulses that the brain can interpret

27. EXTRASENSORY PERCEPTION (ESP)
THE 6th SENSE
EXTRASENSORY PERCEPTION (ESP)

28. PARAPSYCHOLOGY The study of paranormal phenomena.
Over 75 years of research
No evidence of paranormal phenomena exists

29. EXTRASENSORY PERCEPTION
Perception without sensory input.
Energy source?
Sensory receptors?
Paranormal phenomena include:
Astrological predictions, psychic healing, communication with the dead, out-of-body experiences, telepathy, clairvoyance, and precognition.

30. TYPES OF ESP
Telepathy: Mind-to-mind communication. One person sending thoughts and the other receiving them.
Clairvoyance: Perception of remote events.
Precognition: Perceiving future events.