Affiche scientifique : Auditory localization training model

Poster Auditory - Dufour

Auditory localization training model:

Teamwork between audiologist and O&M specialist

Pre-test with a visually impaired person using bilateral cochlear implants

Julie Dufour1, Agathe Ratelle2, Tony Leroux1,3 & Martine Gendron1

  • 1 Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), Institut Raymond-Dewar;
  • 2 Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), Institut Nazareth et Louis-Braille;
  • 3 School of Speech-Language Pathology and Audiology, Université de Montréal
  • Montréal (Québec), CANADA


  • {Logo de l’université de Montréal}
  • {Logo Vision 2008 – Come and discover the unique joie de vivre of Montréal !  }
  • {Logo du CRIR – Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain}
  • {Logo de l’Institut Nazareth et Louis-Braille}
  • {Logo de l’Institut Raymond-Dewar Centre de réadaptation spécialisé en surdité et en communication }


  • Targeted population: hearing and visually impaired people, mainly those affected by Usher syndrome type II.
  • Orientation and mobility (O & M) training:
    • Focus on optimal use of visual strategies;
    • Potential use of advanced auditory skills (alignment, analysis of intersection, etc.): not clearly defined.
  • Clientele’s motivation to preserve independence in street crossings led to teamwork between O&M and audiologist.

Teamwork O&M specialist and audiologist

  • Phase I (2003-2004): Development of an auditory localization training program
  • Phase II (2004): Application to a new user of bilateral cochlear implants (pre-test to validate the program)
  • Phase III (2005…): Evaluation of the program efficiency with different clientele profiles (case study research)

Phase I Auditory localization training program

  • Purpose: To improve auditory skills useful for mobility and to increase feeling of security in travel situations
  • Objectives:
    • To localize an ecological sound source- 1 meter distance- at a precision of 18°
    • To reduce number of front/back inversions
    • To learn specific localization strategies
  • Program description:
    • Modality: One month intensive (3 times a week-1 hour/lesson ), conjointly given by audiologist and O&M specialist in a controlled setting (sound booth)
    • Training equipment: auditory localization evaluation system (SELA) — use of ecological sounds (trafic sounds, pole locator sound, audible pedestrian signal, etc.)
    • Procedure: includes appropriate familiarization, immediate feedback, localization strategies, head and body coordination response
    • Specific objectives: include tasks varying from simple to complex: discrimination (sound comes from same place or not), localization from a closed choice, semi-opened choice (known position), and opened choice (unknown position), with and without background noise — success criteria for each objective

SELA (Auditory Localization Evaluation System )

  • The system is operated from a PC using a standard sound card with additional hardware to control the selection of the active speakers (11) and to collect the client/subject responses automatically. The system was constructed by MEC-INOV of Québec City, Canada, and normalized in 2002 (IRD’s system).


Schéma qui représente l’installation du SÉLA qui est composé de 11 hauts-parleurs disposés en demi-cercle dont le centre est la position du sujet évalué.


Evaluation description

  • Stimulus: broad band noise of 65 dBA, 1,5 sec. duration
  • 3 evaluation positions
    • frontal (subject in front of speaker 6)
    • right lateral (subject in front of speaker 1)
    • left lateral (subject in front of speaker 11)
  • Subject is seated on swivel chair, head and trunk movements allowed
  • Pointing tool: head-mounted laser


At the beginning of training: seating position


Photo du SÉLA qui est constitué de 11 haut-parleurs disposés en demi-cercle. La personne évaluée est assise au centre et porte un casque laser utilisé comme outil de pointage.


Mid-term of training: standing position


Photo du SÉLA qui est constitué de 11 haut-parleurs disposés en demi-cercle. La personne évaluée est debout au centre et porte un casque laser utilisé comme outil de pointage.



Photo de l’outil de pointage : laser monté sur la structure intérieure d’un casque de construction et relié par fil à un bouton pressoir et à une boîte d’alimentation à pile.


Pointing tool : head-mounted laser

Phase II Pre-test


  • Subject description : 50 years old female, little residual vision (2º of field of vision), guide dog user, profound deafness since teen age, new user of bilateral cochlear implants, motivation to use hearing in mobility
  • SELA evaluation prior to training:
    • Observations: stationary sound sources perceived as moving inconstantly, subject not confident in her capability, difficulty to give a response, many front-back confusions
  • Procedure
    • Training was given in two periods: 12 & 9 lessons
    • Modifications of the program were made during the training according to subject’s response


  • After training, success criteria were met for the most advanced objectives
  • Progress was observed from day to day: variable errors and front-back confusions lessened, responses were quicker and more precise; standing position led to better performance and allowed posture correction
  • The person expressed more confidence in her localization capability
  • Post-training SELA evaluation: the progress was less clearly observed, sensitivity questionable


  • Results from pre-test:
    • seem to support the hypothesis that intensive auditory training can enhance localization abilities and confidence (importance of qualitative measurements)
    • indicate that localization evaluation needs to be adapted for better sensitivity

Phase III Case study research

  • Ongoing steps:
    • Reliability and validity of the adapted version of the auditory localization evaluation (standing position, ecological sound source, response mode, etc.)
    • Research project proposal: evaluation of the program efficiency with hearing and visually impaired people presenting localization problem motivated by independant outdoors travel (ex.: new hearing aids users-monaural or binaural, cochlear implant users, etc.)