Behavioral and Neural Characteristics of Adaptive Speech Motor Control
This study meets the NIH definition of a clinical trial, but is not a treatment study. Instead, the goal of this study is to investigate how hearing ourselves speak affects the planning and execution of speech movements. The study investigates this topic in both typical speakers and in patients with Deep Brain Stimulation (DBS) implants. The main questions it aims to answer are: * Does the way we hear our own speech while talking affect future speech movements? * Can the speech of DBS patients reveal which brain areas are involved in adjusting speech movements? Participants will read words, sentences, or series of random syllables from a computer monitor while their speech is being recorded. For some participants, an electrode cap is also used to record brain activity during these tasks. And for DBS patients, the tasks will be performed with the stimulator ON and with the stimulator OFF.
• native speaker of American English
• no communication or neurological problems (except for subjects in the DBS group)
• 250-4000 Hz pure tone hearing thresholds equal to or better than 25 dB HL for children and young adults and equal to or better than 35 dB HL for older adults
• no medications that affect sensorimotor functioning (except for in the DBS group)
• adult subjects: 18 years of age or older
• typical children: 4;0 to 6;11 \[years;months\] or 10;0 to 12;11 \[years;months\])
⁃ \* scoring above the 20th percentile on the Peabody Picture Vocabulary Test (PPVT-5), Expressive Vocabulary Test (EVT-3), Goldman-Fristoe Test of Articulation (GFTA-3), and either Test of Early Language Development (TELD-4) or (for children age 8 or older) Clinical Evaluation of Language Fundamentals (CELF-5).
⁃ \* bilateral electrodes implanted in either the ventral intermediate nucleus of the thalamus (Vim; a target site for patients with essential tremor) or subthalamic nucleus (STN; a target site for patients with Parkinson's disease)