Hearing

Question 1

bones amplify air waves how

Answer 1

1. force - lever system

2. surface area - tympanic membrane larger than oval window

Question 2

Middle ear muscles (2)

Answer 2

1. tensor typani - inserts on malleus, decreases movement of ear drum (CN 5)
2. Stapedius - restricts movement of footplate against oval window (CN 7)

Question 3

A1

Answer 3

area 41 (temporal)

• 6 layer
• granular (afferents)

Question 4

Pathway

Answer 4

hair cells -> spiral ganglion -> cochlear nerve -> cochlear nucleus -> dorsal/int acoustic stria & trapezoid body -> lateral lem -> inf colliculus -> brachium of inf colliculus -> MGB -> A1 temporal lobe

Question 5

lower frequencies =

Answer 5

rostral

Question 6

A1 lesion

Answer 6

• bilateral - don’t lose that much

- some loss of localization

Question 7

Dorsal Stream

Answer 7

• WHERE (how)
• parietal
• localizing sound, using sound to guide movement

Question 8

Ventral Stream

Answer 8

• WHAT
• temporal
• linguistic function - identify sound
• uncinate and arcuate fasciculus

Question 9

Arcuate Fasciculus

Answer 9

language

-connects Wernickes to Brocas

Question 10

Uncinate Fasiculus

Answer 10

what/who making sound

Question 11

Associative cortex

Answer 11

area 42

unimodal

Question 12

Broca

Answer 12

• Areas 44 and 45

- speech

Question 13

Wernickes

Answer 13

• Area 22
• comprehension of language - meaning to words
• ONLY on dominant hemisphere (95% left)

Question 14

Aphasia

Answer 14

• partial or complete loss of language abilities following brain damage
• often without loss of cognitive faculties or ability to more ms used in speech

Question 15

Anomia

Answer 15

inability to find words

Question 16

Alexia

Answer 16

inability to read

Question 17

Agraphia

Answer 17

inability to write

Question 18

Broca’s Aphasia

Answer 18

• nonfluent speech - few words, many pauses
• great effort, sound distorted
• flat intonation
• impaired repetition
• aural comprehension intact
• often accompanying R hemiparesis of face, arm, leg

Question 19

Pure Word Deafness

Answer 19

• bilateral destruction A1
• cortically deaf - can hear but not perceive or comprehend sounds or language
• Wernickes disconnected from input = auditory agnosia
• can detect sounds but not identify
• can speak but not perceive what you’re saying
• still have reflexes (BS)

Question 20

Wernicke’s Aphasia

Answer 20

• no difficulty articulating speech, can’t comprehend

- speaks in meaningless jargon

Question 21

Conduction Aphasia

Answer 21

• knocked out arcuate fasc. - no connection B/W
• fluent paraphasic expression that is characterized by numerous phonetic substitutions
• comprehension intact
• severe impairment of repetition
• reading aloud - paraphasic output but comprehension good
• writing impairment = mild
• frequent self-corrections

Question 22

Transcortical Aphasia

Answer 22

• lesion to cortical border zones surrounding language axis
• can speak but don’t know why it’s important
• depends on lobe affected - have nothing to say

Question 23

Alexia without agraphia - splenium of CC

Answer 23

• disconnection of language center from visual perceptual areas
• can’t read, but other language functions intact
• lesion of L occipital lobe that also includes pathways connecting visual perceptive areas (splenium)
• lose R visual field

Question 24

Angular Cortex (area 39)

Answer 24

• alexia AND agraphia
• projects to language centers
• severe disorder of both reading and writing but auditory comprehension and speech intact