Lexical selection: activates successive lexical items. GENERATION AND DETECTION OF SEGMENTAL ERRORS IN INTERNAL SPEECH Lexical selection: activates successive lexical items. Phonological encoding: per lexical item prosodic frame with slots for successive segments and segments are selected. Selected segments may interact leading to error form. Correct target from may remain active. Encoded form ready for articulation (T1). Selection of motor plan: 100 ms per encoded form. Command for execution of motor plan: 100 ms per syllable. Starting at T1, self-monitoring parses encoded form: 100 ms per encoded form. Parsed encoded form compared with still active target form: 50 ms per encoded form. Error detected at T2: at least 150 ms after T1. (T2 – T1) increases from earlier to later error position. At T2 command to interrupt articulation is issued. In parallel, at T2 command to plan a repair is issued. If correct target is still available, planning a repair is virtually instantaneous. If correct target is not available, planning a repair is time-consuming.