Professor Pisoni’s Current Research Interests:
The long-term objective of my research program is to investigate how spoken words are recognized and how acoustic-phonetic, indexical and lexical information in speech interact with other sources of knowledge and experience in long-term memory to support robust spoken language processing. I have been interested in studying the episodic encoding of the fine acoustic-phonetic and indexical details of speech and the role of “representational specificity in speech perception, spoken word recognition and sentence processing in both normal-hearing listeners and hearing-impaired children and adults who use cochlear implants. I have also been interested in the effects of hearing loss on speech perception and spoken word recognition and the benefits of cochlear implants as a medical intervention to restore hearing and improve speech recognition in profoundly deaf children and adults.
My current research interests have focused on four specific aims: Specific Aim 1: Lexical Knowledge and Organization. To investigate the role of the mental lexicon on spoken word recognition, we have used behavioral and computational methods. We are also studying the effects of perceptual similarity on global lexical organization and lexical connectivity patterns of words in the mental lexicon. Specific Aim 2:Perceptual Learning and Adaptation. To understand the rapid and efficient perceptual learning in speech perception and spoken word recognition, we have studied adaptation to spectrally-transformed noise-vocoded degraded speech processed by a portable real-time vocoder designed to simulate a CI. Studying the perception of acoustically transformed speech in everyday real-world natural environments will provide new basic knowledge about the nature and time-course of perceptual learning and adaptation to a transformed auditory world and the close links that exist between speech perception and speech production. Specific Aim 3:Speech Perception Under Adverse Listening Conditions. To identify the perceptual strategies and underlying neurocognitive factors that NH listeners use to maintain perceptual constancy of speech perception under high variability adverse listening conditions, we have been studying individual differences and variability in listeners to identify underlying differences in basic sensory capacities, processing speed, attention, short-term and working memory capacity, perceptual learning, inhibition and executive control processes. Specific Aim 4:Individual Differences and Working Memory Dynamics. To evaluate the hypothesis that individual differences in verbal working memory capacity in deaf and hearing-impaired children and adults result from a loss of “representational specificity” of phonological and lexical representations in STM and encoding of detailed episodic context, we have used several novel behavioral methods to measure verbal working memory capacity and the important contribution of episodic information and linguistic context in speech perception and spoken word recognition.