Speech Research
Research in the Speech Imaging Lab focuses on the neurophysiological basis of phonemic perception in the temporal cortex. Phonemic perception emerges when the acoustically rich, diverse and continuously varying speech signals are represented as a limited set of discrete, learned phonemic categories.
A main research aim is to determine whether the characteristic pattern of increased response in left ventral temporal regions during phonemic perception is related to the categorical nature of this process rather than strictly to its relevance for language. Another focus of research is on the neural developmental changes associated with the acquisition of phonemic perception in typically developing children.
Insights gained from these normative studies in healthy adults and children will serve as a basis to examine the role of speech perception deficits in developmental learning disabilities affecting language processing, and in particular dyslexia.
We are using behavioral and neuropsychological measures, functional magnetic resonance imaging, event-related potentials recordings collected simultaneously with fMRI, and diffusion tensor imaging to gain comprehensive spatial, temporal and connectivity information regarding the cortical substrates mediating phonemic perception.
Research Highlight
The figure below shows an area in the left anterior Superior Temporal Sulcus that responds more to phonemic than nonphonemic stimuli (from Cerebral Cortex, 2005).
Current Funding
R01 DC006287-01Neurophysiological Basis of Speech Perception
Einat Liebenthal, D.Sc., Principal Investigator
