Auditory Perception -- Hearing

Auditory Stimulus:

sound wave: a pattern of successive pressure disturbances occurring in a medium like air or water

 

 

e.g. stereo speaker-

 

Anatomy of the Ear:

Outer Ear:

• pinna:

 

 

• auditory canal:

 

 

• tympanic membrane (eardrum):

 

 

 

Middle Ear: -- separates outer ear (air medium) and inner ear (liquid medium)

• Ossicles: the 3 bones of middle ear (tiniest in human body)

1. malleus (hammer)

2. incus (anvil)

3. stapes (stirrup)

 

• Oval Window:

 

 

 

 

 

Inner Ear:

• Cochlea - (liquid filled.)

 

 

• Basilar Membrane -

 

 

Pitch Perception:

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Loudness Perception:

• Loudness perception is determined by 2 things:

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• Some hearing loss results from loud noises that damage the hair cells (cells bend or tear off)

 

Sound Localization: -- how do we determine which direction a sound is coming from?

• Interaural time difference: composed of

• Onset difference-

 

 

 

• Interaural intensity difference:

 

 

Chemical Senses (Taste and Smell)

• Smell and Taste receptors both respond to the presence of chemical substances.

Smell (Olfaction)

Stimulus: airborne molecules or vapors

 

Anatomy:

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• olfactory receptors respond to a variety of odors, and the overall pattern of responding results in the perception of a particular scent

 

 

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• receptors are linked directly to brain (don't go through spinal cord and brain stem) linked to olfactory cortex & limbic system (amygdala).

• memory:

 

 

 

 

• emotion:

 

 

 

 

Taste (Gustation) -

Stimulus: any substance/chemical that dissolves in saliva.

• 5 basic taste categories: sweet, sour, salty, bitter, and "umami" (Japanese word for meaty or savory produced by MSG)

 

Anatomy:

• tongue is a muscle covered with mucous membrane containing little bumps (papillae).

 

 

 

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• most taste buds respond to multiple substances such as both acids and salts, but respond maximally well to only one type.

 

 

 

• Perception of Smell and Taste senses are intertwined

 

 

 

Taste Thresholds and Tongue Regions: all areas on tongue respond to all flavors (except middle which is like the "blind spot")--but certain flavors are more noticeable on certain areas.

• sides of tongue

 

• front of tongue

 

 

• soft palate (roof of mouth in back)

 

 

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Cutaneous Perception

Touch:

 

 

 

Density of Nerve Fibers:

 

 

 

 

Two-point thresholds: the smallest distance of two separate points of stimulation on skin that just produces the perception of 2 distinct points.

 

Touch linked with kinesthesis and proprioception.

Kinesthesis:

 

 

 

Proprioception: