General Principles Part 1 Historical And Classifications
Upcoming SlideShare
Loading in...5
×
 

General Principles Part 1 Historical And Classifications

on

  • 1,638 views

General Principles Part 1 Historical And Classifications

General Principles Part 1 Historical And Classifications

Statistics

Views

Total Views
1,638
Views on SlideShare
1,260
Embed Views
378

Actions

Likes
1
Downloads
8
Comments
0

3 Embeds 378

http://mycourses.atsu.edu 217
http://mywebct6.atsu.edu 85
https://mycourses9.atsu.edu 76

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

General Principles Part 1 Historical And Classifications General Principles Part 1 Historical And Classifications Presentation Transcript

  • AUD 744 Overview of Auditory Evoked Responses Transitional Audiology Program AUD 616 Auditory Evoked Responses Residential Audiology Program Henry P. Trahan, Au.D.
    • Part 1
    • Auditory Evoked Responses
    • Historical Overview
    • And
    • General Principles
    • 1929 – Human EEG -- Berger
    • 1930 – First paper on AEPs in general -- Weaver and Bray
    • 1930 – Earliest of AEPs discovered – Cochlear Microphonic – Weaver and Bray
    • 1939 – First recorded alteration in EEG with auditory stim. in humans – P. Davis
    • 1941 – CM recorded from round window in human through TM perforation – Pearlman and Case
    Historical Time Line Henry P. Trahan, Au.D.
    • 1950 – Summating Potential in animal recorded – Davis
    • 1958 – Description of average response computer (ARC) – Clark
    • 1967 – AP with earlobe electrodes. ABR response first shown but reported as ECochG – Sohmer and Feinmesser
    • 1971 – AP recorded in human w/external ear canal electrode – Saloman & Elberling
    Historical Time Line Henry P. Trahan, Au.D.
    • 1971 – ABR first described in animals - Jewett
    • 1971 – ABR response first described in humans – Jewett, Romano, Williston
    • 1974 – CM, SP, and AP record in human w/ ear canal electrode -- Coats
    • 1974 – Relationship between ECochG abnormalities and Meniere’s disease – Eggermont
    • 1974 – Description of ABR in infants & young children – Hecox and Galambos
    Historical Time Line Henry P. Trahan, Au.D.
    • Electrical potentials in the human nervous system can be recorded both in response to specific external stimuli (event-related potentials [ERP] ) and in an ongoing manner without the presence of external stimuli (non-evoked or non-event related).
    Evoked Versus Non-Evoked Responses Henry P. Trahan, Au.D.
    • Non-Event Related Event Related
    • EEG ECochG
    • ABR
    Evoked Versus Non-Evoked Responses Henry P. Trahan, Au.D.
    • Auditory Evoked Responses (AERs) represent electrical responses of the Auditory nervous system to externally presented acoustic stimuli.
    Auditory Evoked Responses Henry P. Trahan, Au.D.
    • AEPs can be classified according to whether their characteristics are determined by external or internal processes ( exogenous vs. endogenous )
    • AEPs can be classified according to the time epoch following the stimulus in which they occur. ( latency )
    • AEPs can be classified according to the relation of the recording electrodes to the actual generator sites. ( Near Field vs. Far Field )
    • AEPs can be classified according to what structures in the auditory system generates them .
    Classification of Auditory Evoked Responses Henry P. Trahan, Au.D.
  • Classification of Auditory Evoked Responses Henry P. Trahan, Au.D.
    • AEPs can be classified according to whether their characteristics are determined by external or internal processes.
      • Exogenous
      • Endogenous
  • Classification of AEPs
    • AEPs can be classified according to the time epoch following the stimulus in which they occur.
      • Very Early (0 – 1.5 msec) (First) (CM, SP, N1) (ECochG)
      • Early (1.5 -12 msec) (Fast) Nerve and brainstem) (ABR)
      • Middle (12 - 50 msec) (thalamus and aud. cortex) (MLR)
      • Slow (50 – 300 msec) (1 o and 2 o areas of cortex) (ALR)
      • P300 (300+ msec) ( 1 o and association areas) (P300)
  • The Family of AEPs
  • The Family of AEPs vertex positive I II III IV V VI N o P o N a P a N b P1 N 1 P2 N2 P300
  •  
  • Classification of AEPs
    • AEPs can be classified according to the relation of the recording electrodes to the actual generator sites.
      • Far-Field Response (Electrodes some distance away)
      • Near-Field Response (Electrodes in close proximity)
    • Clinically, AEPs are almost always recorded at far-field., with electrodes located outside of the skull (extracranially), usually at the scalp. Two exceptions are:
      • During intraoperative monitoring (when recording electrodes mat be placed directly on the VIIIth Nerve) and
      • During transtympanic membrane ECochG, (when a recording electrode may be placed on the promontory).
    • AEPs can be classified according to what structures in the auditory system generates them.
      • Receptor Potentials (cochlear hair cells)
      • Neurogenic Potentials (VIIIth N &/or brain stem)
    Classification of AEPs