Software for Characterizing Laryngeal Dynamics

Our company will create a software "tool" to characterize aspects of the structure andperformance of the larynx from analysis of speech. The analysis relies on the theory of nonlineardynamical systems, or "chaos theory". It provides parameters (Lyapunov exponents, metric entropy,attractor dimensions) which cannot be derived from conventional reduction but which have already beenshown to have value in characterizing the larynx as a dynamical system. The technique is non-invasive,and the software will accept continuous speech and even some unrequested vocalizations, as fromneonates. The tool will be capable of detecting both unusual glottal periodicities and completeaperiodicity (chaos). There are both physiological and mathematical reasons to expect some distinctpathologies to excite distinct dynamical responses which the tool can distinguish. Phase I will verify thatthe tool can reliably determine the exponents and the attractor dimensions for entries in an existingdigital data base of vocalizations; show that the parameters identify distinct modes of stable vibration;and determine the extent to which the parameters vary with known laryngeal conditions. If successful,this software will provide a new set of clinical "measurements" for assisting in the diagnosis of laryngealpathologies. It can then provide objective corroboration for clinical judgments.