Lab 6 - Vision and Hearing Tests Procedures

Blind spot = _____ = part of the retina with _____.

- "optic disc" - only disc

Two types of deafness: _____.

- Conductive deafness - Sensory deafness

_____ results from damage in the _____ ear; caused by _____, damage to ____, _____ infection, _____ infection, excessive _____, etc.

- Conductive deafness - outer or middle ear - obstruction to external auditory meatus - ossicles - middle ear - tympanic membrane - ear wax

Sound Localization For sound to be accurately located, the brain must perceive 2 things: 1. _____ reaching each ear (difference of intensity caused by _____ from each side) 2. _____ at each ear.

- Difference in loudness of the sound - different frequencies of A.P. - Difference in the time of arrival of the sound

_____, _____ and _____ can be detected by observing the retina with an ophthalmoscope.

- Retinal detachment - cataract - glaucoma

_____ results from damage anywhere between _____(cochlea) to _____(temporal lobe), including _____(CN VIII); caused by inner ear infection, any death to _____ (prolonged exposure to loud noises or explosive sounds), CN detachment, _____ to perceive sound (damage to the temporal lobe)

- Sensory deafness - inner ear - brain -vestibulocochlear nerve - hair cells - inability

In the blind spot demonstration, _____ in place of the figure that disappeared. "Seeing" occurs in the _____ because the brain is filled with the _____, thus we are not aware of the blank spots which is the area just background.

- a blank focus - brain - background

The image seen through the paper roll will suppress _____ of the hand. Note: The hand will generally stay suppressed because it is the "_____" (the images need to be "_____" for rivalry - if you hold still and face a blank wall you might get rivalry between the wall and hand in the _____).

- a section - weaker stimulus - equal strength - central patch

During _____ all/part of one image appears totally _____ from consciousness. - To experience this suppression yourself 1) roll up some paper like a _____. 2) look through it with your right eye and put your left hand next to the paper roll a few inches in front of your _____.

- binocular rivalry - suppressed - telescope - left eye

Near Point of Vision depends on _____, which _____. Approx _____ in young adults, _____ in children and _____ in old age.

- elasticity in the lens - decreases with age - 10 cm - closer - farther

Tests of the Extrinsic Eye Muscles, 6 extrinsic eye muscles allow eyes to _____. If _____ of one muscle is weak, eye will slowly _____, followed by rapid movement back to correct position, called _____.

- follow moving objects - tone - drift in a direction - nystagmus

Weber's Test Normal ear _____. Ear with conductive deafness _____. Ear with sensory deafness _____.

- hears the TF sound equal in both ears. - hears the sound LOUDER in the deaf ear because the good ear hears the TF and ambient noise, but the bad ear only hears the TF - hears nothing

Rinner's Test Normal ear: ______. Ear with conductive deafness _____. Ear with sensory deafness _____.

- hears tuning fork (TF) on bone and hears TF when in front of ear canal - hears TF on bone, and cannot hear TF when in front of ear canal - hears nothing

It is possible that two people of the same age have very different near point measurements may because ______. For instance, being explored on the beach without eye protection _____ because the light reflect through the water is much brighter than looking directly at the sun.

- lifestyle and genetics - burns the structure of the eye

Visual awareness is _____ always an accurate representation of reality because parts of visual fills are _____. For example, in the demonstration of _____, either the circle or the cross disappeared, but neither the circle nor the cross disappeared in the reality.

- not - suppressed - the blind spot

Pupillary light reflex, pupils _____ in bright light and ____ in dim light. Absence of normal pupillary reflex's indicates _____.

- shrink - enlarge - severe brainstem damage

When light hits _____, we cannot perceive it. To demonstrate: put the paper about 2" from face; close left eye and look at the _____; slowly move the paper away from your face; when _____ disappears, you found the ______.

- the blind spot - circle - + - blind spot

Sound is located by ______, and _____. We are often inaccurate locating sound that originates in the midsagittal plane because ______.

- the brain perceiving difference in loudness of the sound reaching two ears - difference in the time of arrival of the sound at each ear - the brain has a difficult time perceiving the difference in loudness of the sound reaching each ear, and difference in the time of arrival of the sound to each ear

The results of Rinne's Test in someone with conductive hearing loss hears ______. Someone with sensory hearing loss hears _____. The results of Weber's testes in someone with conductive hearing loss hears ______, but the good ear hears the tuning fork and ambient noise. Another person with sensory hearing loss hears _____.

- tuning fork on the bone, and cannot hear tuning fork when in front of the ear canal - nothing no matter on the bone or in front of the ear canal - the sound louder in the deaf ear because the deaf ear cannot hear ambient noise - nothing

20 --- ? 20

Average vision. Top 20 means when you are 20' away, you see what. Bottom 20 means the average person sees from 20' away.

20 ---? 10

Better than average vision. Top 20 means when you are 20' away, you see what. Bottom 10 means the average person sees from 10' away.

Color blindness tests, uses _____ about 30" away and at right angles to the line of vision

Ishihara's color plates

Observation of retina, study the photograph of a retina as seen through an ophthalmoscope. Which structures are visible?

Optic nerve and fovea.

A visual acuity (Sharpness) is tested with _____.

Snellen Eye Chart

20 ---? 40

Worse than average vision. Top 20 means when you are 20' away, you see what. Bottom 40 means the average person sees from 40' away.

Vision and hearing tests are given as part of a regular physical exam and to young children before starting school because _____.

detecting any vision and hearing abnormalities to request special accommodations to avoid delaying learning

Binocular rivalry is ______.

phenomenon of visual perception