Cochlear Implants and Listening Effort: the Interaction of Cognitive and Sensory Constraints

Обзор

This study examines how cochlear implant users understand and comprehend speech in realistic communication situations. Through six experiments measuring listening effort via pupillometry and discourse comprehension, we will investigate how linguistic context, cognitive demands, and processing time affect speech understanding in CI users, and in normal-hearing controls) to identify factors underlying communication resilience versus vulnerability and develop improved, ecologically valid assessment and rehabilitation strategies.

Подробное описание

This research study examines how adults using cochlear implants (CIs) understand and comprehend speech in realistic communication situations. While current clinical tests focus on how well CI users can recognize single words and simple sentences, this study investigates whether success in recognizing speech sounds actually translates to understanding the meaning and content of longer conversations and discourse.

The study will include six interconnected experiments examining: (1) how CI users use linguistic context (both adaptively and maladaptively) to understand degraded speech; (2) how listening effort affects comprehension when faced with communicative challenges like remembering multiple sentences or narratives; (3) whether giving listeners control over the speed of speech presentation improves comprehension; and (4) a clinically-applicable version of these assessments.

Throughout the experiments, researchers will measure listening effort using pupillometry (tracking pupil dilation as an index of cognitive effort) combined with behavioral measures of speech recognition and comprehension. Comprehension will be assessed using a validated framework that distinguishes between understanding main ideas versus minor details in discourse passages.

The study will include cochlear implant users and normal-hearing adults listening to degraded speech simulations via vocoders. Participants will range in age from 18 to 80 years. A comprehensive baseline battery will assess perceptual abilities (speech recognition, spectral resolution, temporal processing) and cognitive abilities (working memory, processing speed, executive function).

OBJECTIVES:

Primary objectives are to identify mechanisms underlying successful speech comprehension in CI users and to determine factors associated with resilience versus vulnerability to communicative challenges. Secondary objectives include examining relationships between cognitive abilities, listening effort, and discourse comprehension outcomes.

OUTCOMES:

This research is expected to provide more ecologically valid assessment methods for CI users, identify which individuals may benefit from specific communication strategies (such as self-paced speech), and inform development of improved rehabilitation approaches that enhance real-world communication success rather than just word recognition ability.

Вмешательства

• Поведенческое Experiment 1: Syntactic and Semantic Context
  * Recall of meaningful sentences, anomalous word strings, and unstructured word lists * Measurement of syntactic and semantic gain * Pupillometry during auditory and visual presentation
• Поведенческое Experiment 2: False Hearing and Context Overuse
  * Two-choice word recognition task with semantic priming/luring in multi-talker babble * Three Signal-to-Noise Ratio (SNR) levels (heavy, medium, light noise) * Confidence ratings for responses * Pupillometry measurement
• Поведенческое Experiment 3: Two-Sentence Problem
  * Speech recognition and recall of single sentences vs. paired sentences * Manipulation of inter-sentence semantic predictability (high vs. low) * Four test conditions: 1-sentence, 2-sentences, 2-sentences+pre-prompt, 2-sentences+post-prompt * Pupillometry during task
• Поведенческое Experiment 4: Cascading Effects on Discourse Comprehension
  * Recall of 27 narrative passages (67-97 words each) * Propositional analysis scoring (main ideas, mid-level ideas, details) * Measurement of semantic hierarchy effect * Pupillometry during listening
• Поведенческое Experiment 5: Self-Paced Discourse Comprehension
  * 24 discourse passages (150 words each): 12 narrative, 12 expository * Continuous presentation vs. self-paced presentation (stops at clause/sentence boundaries) * Measurement of pause times and comprehension recall * Pupillometry during task
• Поведенческое Experiment 6: Clinical Application
  * Self-Paced Sentence Comprehension * Sentences with varying syntactic complexity (active-conjoined, subject-relative, object-relative) * Continuous vs. self-paced (with pause at major clause boundary) presentation * True/false comprehension verification statements * Pupillometry measurement

Первичные конечные точки

• Percent correct Consonant-Nucleus-Consonant (CNC) words across experiments 1-3 [Срок оценки: End experiments 1-3 (up to 9 hours)]
• Percent correct AzBio sentences across experiments 1-3 [Срок оценки: End experiments 1-3 (up to 9 hours)]
• Error rates for word identification tasks across experiments 1-3 [Срок оценки: End experiments 1-3 (up to 9 hours)]
• Percentage of propositions recalled from narrative passages [Срок оценки: End of experiment 4 (up to 3 hours)]
• Ratio of main idea recall to detail recall [Срок оценки: End of experiment 4 (up to 3 hours)]
• Percentage of true/false statements identified [Срок оценки: End of experiment 6 (up to 3 hours)]
• Percent correct increase from unstructured word lists to anomalous sentences (syntactic gain) [Срок оценки: End of experiment 1 (up to 3 hours)]
• Percent correct increase from anomalous sentences to meaningful sentences (semantic gain). [Срок оценки: End of experiment 1 (up to 3 hours)]
• Number semantically-driven misrecognitions in lure conditions [Срок оценки: End of experiment 2 (up to 3 hours)]
• Frequency of semantically-driven misrecognitions in lure conditions [Срок оценки: End of experiment 2 (up to 3 hours)]

Критерии участия

Критерии включения

• Subjects will be otherwise healthy normal-hearing and cochlear implant (CI) adult listeners (between 18 and 80 years old).

Критерии исключения

• Individuals below 18 years of age.
• Individuals with evidence of neurologic, vascular or psychiatric disease or dementia, and taking medications that might interfere with task performance.
• Individuals with a history of language disorders (besides those associated with hearing loss for the CI users). Individuals who are non-native speakers of American English.

Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.

Здоровые добровольцы: Да

Дизайн исследования

Распределение

Нерандомизированное

Модель

Параллельные группы

Маскирование

Открытое

Основная цель

Другое

Центры проведения

США · 2 центра

• Brandeis University — Waltham
• NYU Langone Health — New York

Идентификаторы

NCT: NCT07279441 · 18-01806 · 2R01DC016834-06A1

Первоисточники (государственные реестры)

• ClinicalTrials.gov (NIH, США)

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