Trial lecture
Place: Auditorium 2, Helga Engs hus
Time: 10:00 - 10:45
Title: Discuss the role of auditory rapid word learning from a developmental perspective
Public Defence
Place: Auditorium 2, Helga Engs hus
Time: 12:00 -
Evaluation committee
- 1st opponent: Professor Viveka Lyberg Åhlander, Åbo Akademi Finland
- 2nd opponent: Docent Olof Sandgren, Lunds Univeritet, Sverige
- Chair of committee: Associate Professor Ellen Irén Brinchmann, Special Needs Education, Universitetet i Oslo, Norge
Chair of defence:
- Professor Ona Bø Wie, Special Needs Education, University of Oslo, Norway
Supervisors
- Björn Lyxell, Professor, Department of Special Needs Education, University of Oslo, Norway
- Elaine Hoi Ning Ng, Principal Researcher, Centre for Applied Audiological Research, Oticon A/S, Denmark
- Kathleen Faulkner, Senior Researcher, Centre for Applied Audiological Research, Oticon A/S, Denmark
- Lone M Percy-Smith, Adjunct Professor, Copenhagen Hearing and Balance Centre, Rigshospitalet, Denmark
Summary
Learning a novel word requires two steps: first, recognizing that the word is new, and second, associating the sequence of sounds in the novel word with its meaning. Distortions in sound, caused by noise or hearing impairment, affect how precisely each sound in a word is perceived. This ambiguity can lead to confusion when trying to learn novel words, making it harder for the brain to process the sound, and slowing learning. This thesis aimed to investigate how changes in the perception of speech affect how the brain processes novel words during learning. To address this, a method called pupillometry was used. Eye pupils are known to dilate when the brain detects novelty and also dilate to the level of effort invested in a task. By observing the pupils of 60 participants, both children and adults, with and without hearing impairments, it was possible to gain insights into how our brains process novel words. The findings indicate that adults when using simulated cochlear implants were 32% more likely to miss word novelty, and they were 26% to 72% slower in learning word meanings. Pupillometry revealed that the brain struggled to identify the presence of a novel word, but also that adults who invested more energy in learning the meaning of words learned faster. Children with hearing impairment (7 to 12 years old) were as efficient as their peers at learning word forms and meanings, but they were less accurate in recognizing novel words, causing them to miss learning opportunities. However, pupillometry did not show differences between how children with and without hearing impairment process novel words. Overall, this thesis contributes to a new methodological approach to pupillometry, which accounts for the effects of learning during a task and brings new insights into the interpretation of pupil responses during auditory word learning.
This work was carried out in Oticon A/S, Denmark in collaboration with the Department of Special Needs Education, University of Oslo.