Guided Notes for PPT #2 Senses Hearing, Equilibrium, and Sight Name:______

HEARING:

Hearing is actually just a response to______

Equilibrium is the sense of ______

Both senses reside in the inner ear within a maze of fluid filled passages and sensory cells.

Sensory cells convert this motion into a pattern of ______

How is Sound made??

Sound is any ______

Air molecules hitting the eardrum cause it to vibrate which generates sound.

Pitch is determined by the frequency (Hertz or cycles/sec, wavelength)of the sound…….High or low

Loudness is the intensity or amplitude of the vibration, recorded in decibels.

Humans have a general range of 20Hz to 20,000Hz

Normal human speech is at about ______which is where human hearing is most accurate.

Humans lose the ability to detect sounds as they age.

How High could you still hear???______

Anatomy of the EAR

Basically 3 sections Outer, Middle and Inner

Outer and middle facilitate the transmission ______

Inner is where______

Outer ear has only basically 2 structures:

Pinna and a tube called the ______. They are designed to collect ______

Middle ear is located in the ______

Structures of middle ear:

Tympanic Membrane ( )______

Separates it from the ______

Vibrates freely______

Innervated by ______

And is VERY sensitive to pain!!

Tympanic cavity: contains the ______(ear bones).

Eustachia tube (auditory tube)______

Equalizes air pressure on both sides of the tympanic membrane

Normally flattened and ______

Allows ______

Auditory ossicles (Bones) 3 smallest in your body

Malleus______

Incus______

Staples______

Inner Ear: Actual center ______

Has semicircular canals:___fluid filled ______

Cochlea is the ______

This is connected to the ______which relays info to the ______in the cerebrum.

Physiology of hearing:

In the tympanic space, the ossicles ad their muscles have a protective function, to______

______

Middle Ear muscles help to coordinate speech with hearing by______

Stimulation of Cochlear hair cells occures by the vibrations of the middle ear bones, as many as ______.

Deafness, can be cause by :

Damaged tympanic ______

Otosclerosis is the ______

Can also be caused by nerve damage, Sensorineural deafness:______

______

Auditory Projection Pathway:

Sensory fibers begin at the bases of the hair cells in the cochlea. Cell bodies form the ______

Axons lead away from the cochlea as the ______

This cochlea nerve joins with the ______to form the

______also known as the ______.

Each ear sends nerve fibers to ______which end in the cochlear nuclei

Neural fibers then rise to the midbrain which helps______

______.

Neurons then lead to the thalamus to the primary______.

This primary auditory cortex lies on the top of the ______which is the site

______

Equilibrium: the coordination ______

The apparatus that hold receptors for equilibrium are the ______

These ______have 3 semicircular ducts______

And 2 chambers that are responsible for ______

What is static equilibrium?______

Dynamic equilibrium is the perception of motion or acceleration

Linear acceleration______

Angular acceleration______

Sight and Vision

Conjunctiva=______

This is richly innervated and vascular.______

• three principal components of the eyeball

– three layers (tunics) that form the wall of the eyeball

– optical component – admits and focuses light

– neural component – the retina and optic nerve

TUNIC LAYERS:

1. Tunic fibrtosa______

Sclera______

Cornea, still sclera but transparent and clear so that light can be admitted into the eye

2. Tunic Vasculosa ______

Choroid______

Ciliary body______

Iris______

3. Tunic Interna______

OPTICAL COMPONENT Transparent elements that ______

______

1. Cornea______

2. Aqueous humor______

3. Lens______

Neural Component Includes the retina and optic nerve

1. Retina______

Attached to the eye______

Pressed against the rear of______

Detached retina causes ______

2. Optic nerve ______transmits signals to the brain

Formation of an Image:

Light passes through the ______

Light energy is converted to Action Potentials in the retina!!

Rod and cone cells are the light absorbing cells.

Rod cells: used for night vision or monochromatic vision

Cone cells: used to capture color and are photopic..day vision

Bipolar cells ______

Ganglion cells______

______

Generating an Optic Nerve Signal

Rod and cone cells release glutamate when stimulated. This in turn activates bipolar cells of the retina to release neurotransmitters which in turn stimulate retinal ganglion cells whose axons form the optic nerve.

Visual Projection Pathway

The two optic nerves combine to form the optic chiasm.

Half the fibers______

Right cerebral hemisphere sees______

______

Each side of the brain sees what is ______

______

Processing of Visual Information:The Primary Visual Cortex ______to the Visual Association areas in the ______which process retinal data from the ______lobes.

Such as object location, ______

______

Muscle Control of the Eye

6 muscles attach to the exterior of the eye

Superior, inferior, medial and lateral rectus muscles move the eye up,

down, medially & laterally

Superior and inferior oblique turn the “twelve o’clock pole” of each

eye toward or away from the nose

innervated by cranial nerves III, IV and VI