26To minimize the number of errors in speech, and thereby facilitate 27 communication, speech is monitored before articulation. It is, however, unclear at 28 which level during speech production monitoring takes place, and what mechanisms 29 are used to detect and correct errors. The present study investigated whether 30 internal verbal monitoring takes place through the speech perception system, as 31proposed by perception--based theories of speech monitoring, or whether 32 mechanisms independent of perception are applied, as proposed by production--33 based theories of speech monitoring. With the use of fMRI during a tongue twister 34 task we observed that error detection in internal speech during noise--masked overt 35 speech production and error detection in speech perception both recruit the same 36 neural network, which includes pre--supplementary motor area (pre--SMA), dorsal 37 anterior cingulate cortex (dACC), anterior insula (AI), and inferior frontal gyrus (IFG). 38Although production and perception recruit similar areas, as proposed by 39 perception--based accounts, we did not find activation in superior temporal areas 40 (which are typically associated with speech perception) during internal speech 41 monitoring in speech production as hypothesized by these accounts. On the 42 contrary, results are highly compatible with a domain general approach to speech 43 monitoring, by which internal speech monitoring takes place through detection of 44 conflict between response options, which is subsequently resolved by a domain 45 general executive center (e.g., the ACC). 46 47 3