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Previous studies have demonstrated the importance of both kinesthetic and auditory feedback for control of voice fundamental frequency (F0). In the present study, a possible interaction between auditory feedback and kinesthetic feedback for control of voice F0 was tested by administering local anesthetic to the vocal folds in the presence of perturbations(More)
Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG(More)
1. Small 'step' or sinusoidal displacements were imposed on the mandible while human subjects maintained an average biting force of 10 N. Phase-related changes in the force resisting sinusoidal displacement were used to determine the mechanical stiffness of the human mandibular system as a function of the frequency of stretching. 2. Jaw-muscle(More)
Recent studies have shown that when phonating subjects hear their voice pitch feedback shift upward or downward, they respond with a change in voice fundamental frequency (F0) output. Three experiments were performed to improve our understanding of this response and to explore the effects of different stimulus variables on voice F0 responses to pitch-shift(More)
Auditory feedback has been suggested to be important for voice fundamental frequency (F0) control. The present study featured a new technique for testing this hypothesis by which the pitch of a subject's voice was modulated, fed back over earphones, and the resultant change in the emitted voice F0 was measured. The responses of 67 normal, healthy young(More)
When air conducted auditory feedback pitch is experimentally shifted upward or downward during steady phonation, voice pitch changes in response. The first pitch change is an automatic deflection opposite in direction to the feedback shift. It appears to help stabilize voice pitch by counteracting unintended changes. But what happens during an intended(More)
Recent studies done on healthy older individuals have demonstrated elevated taste thresholds for sweet, sour, and salty taste. At suprathreshold levels, such individuals have also shown less ability to discriminate between different intensities of the same tastant. This study was designed to provide information on swallow timing and muscle contraction(More)
BACKGROUND The motor-driven predictions about expected sensory feedback (efference copies) have been proposed to play an important role in recognition of sensory consequences of self-produced motor actions. In the auditory system, this effect was suggested to result in suppression of sensory neural responses to self-produced voices that are predicted by the(More)
Experiments were performed on one Macaca fascicularis and three Macaca mulatta monkeys. Electrical stimulation of the midbrain periaqueductal gray (PAG) elicited phonation closely resembling that naturally produced by such animals. Electromyographic (EMG) recordings from laryngeal, thoracic, tongue, and facial muscles showed increased levels of activity(More)
Recent research has found that while speaking, subjects react to perturbations in pitch of voice auditory feedback by changing their voice fundamental frequency (F0) to compensate for the perceived pitch-shift. The long response latencies (150-200 ms) suggest they may be too slow to assist in on-line control of the local pitch contour patterns associated(More)