A ‘Basin of Attraction’ Theory of Speech Initiation and Stuttering

AbstractPurpose. Recent work in motor neuroscience suggests that well-learned actions are implemented as stable, stereotyped trajectories in neural state space. The purpose of this article is to propose a theory of stuttering that formalizes this idea for speech production and identifies a specific neural impairment underlying speech dysfluency.Method. We advance a conceptual and computational framework in which the motor program for a familiar word corresponds to a stable neural trajectory with an associated basin of attraction. We integrate findings from primate motor control, human speech neuroscience, and basal ganglia physiology to specify the role of cortico–basal ganglia–thalamo–cortical (BGTC) circuits in initiating these trajectories.Results. We propose that fluent speech depends on the ability of the BGTC circuit to initialize the distributed speech motor network within the basin of attraction of the upcoming word’s motor program. Stuttering arises when this initialization process is unreliable or poorly coordinated, preventing the motor program from being executed until the neural state is corrected or the effective basin of attraction is broadened through compensatory mechanisms.Conclusions. This basin-of-attraction framework provides a unifying account of diverse behavioral and neural findings in stuttering, aligns stuttering theory with contemporary dynamical systems approaches to motor control, and generates testable predictions for future neurophysiological and neuroimaging studies.