Randomised Study of Web-Based Auditory Training With Varying Perceptual and Cognitive Demands on Training Gains and Generalised Speech, Cognitive, and Communication Outcomes

WP1: PLUS-Auditory Training The goal of this experimental study is to better understand how task difficulty affects on-task learning thresholds and generalised benefits in two PLUS auditory training tasks involving perceptual and cognitive learning in adults aged 18+ (no upper age limit) with listening difficulties. The main question it aims to answer is: * Does adjusting task difficulty in PLUS, by manipulating the perceptual and cognitive demands of the phonemic discrimination and competing speech tasks, affect on-task learning thresholds and off-task performance in adults with listening difficulties? Researchers will compare the two experimental arms (easy/hard) to see whether adjusting task difficulty influences on-task learning thresholds and off-task performance. Participants will: * Be randomly assigned to one of two training programs (phonemic discrimination or competing speech) within the two experimental arms (easy/hard); * Perform training for a minimum of 30 minutes per day, 5 days per week, for two weeks (total 10 training sessions, 5 hours of training); * Complete pre- and post- training assessments to measure on-task learning performance and change in performance for untrained measures of speech perception, cognition and self-reported outcomes. WP2: Post-Training Focus Groups The goal of this observational study is to gain in-depth qualitative insights into participants' motivations, experiences of task difficulty, and perceived benefits across the PLUS-AT training groups in adults aged 18+ (no upper age limit) with listening difficulties. The main question it aims to answer is: * How do participants describe their experiences and perceptions of PLUS-AT, particularly regarding task difficulty and self-perceived changes in listening, hearing, thinking, and quality of life? Researchers will explore participant experiences across the two experimental arms (easy/hard) to determine whether motivations for seeking auditory training, knowledge and beliefs about auditory training, attitudes toward PLUS-AT difficulty, and self-perceived changes in listening, hearing, thinking, and quality of life differ. A subset of participants (n = 20) will: * Be invited from WP1 to join one of four online focus groups (60-90 minutes via Microsoft Teams); * Attend the focus group corresponding to their assigned training program (phonemic discrimination or competing-speech) within the two experimental arms (easy/hard); * Share their experiences of completing PLUS-AT.