The field seems to be a bit divided on this question as the following quotes indicate.
"...many patients with Broca’s aphasia actually do show severe phonemic perception deficits..." (Wilson & Iacoboni 2006)
"Broca’s aphasia is associated with speech perception deficits..." -Iacoboni, in Gallese et al. 2011
"The findings reviewed in the present paper indicate that areas in the frontal lobe involved in speech production are specifically contributing to speech perception, and that activity in the motor system can alter speech discrimination, directly indicating that sensory-motor processes interact during speech comprehension. The experimental evidence of a causal relationship between activity in motor areas and speech perception ([D'Ausilio et al., 2009] and [Meister et al., 2007] ) provide evidence that activation of motor areas during listening to speech is NOT the consequence of a corollary cortico-cortical connection ... but reflects the sensory-motor nature of perceptual representations." (D'Ausilio, et al. 2010)
“…lesion studies show that aphasics with damage to frontal motor-related structures largely retain the ability to perceive speech sounds.” (Hickok 2010)
A critical piece of evidence in this debate is the speech perception ability of individuals with damage to Broca’s area and/or Broca’s aphasia. Proponents of the view that damage to frontal, motor-related regions are critically involved in speech perception often refer to the literature of the 1970s and 1980s which reported various degrees of impairment on some speech perception tasks. But this older literature did not typically utilize neuroradiological data to confirm the location of the lesions, nor did these studies use signal detection methods.
I recently had the opportunity to team up with one of the major players in that earlier literature, Gabriele Miceli and his group, to re-examine this issue in a new sample of aphasics. From Miceli’s database of patients, we identified all of the cases that had substantial damage to Broca’s area, confirmed radiologically; the lesions typically involved surrounding regions as well. Twenty-four cases were identified. Nineteen were classified as Broca’s aphasics, 5 were on the border between Broca's and conduction aphasia, and 1 was classified as a conduction aphasic.
We assessed the ability of these patients to perceive speech sounds using a variety of tasks including same-different syllable discrimination and auditory word-to-picture matching with phonological and semantic distracter pictures. Of course, if Broca’s area and surrounding motor regions are critical for speech sound perception, we would expect to find substantial deficits on our tasks.
In fact, performance was remarkably good. On the syllable discrimination task the group averaged 94% correct with a d’ = 4.18, i.e., 4 standard deviations above chance performance. On the auditory comprehension task, performance was even better at 97% correct. Task still matters!
Speech output fluency varied across the sample. There was one fluent aphasic in the sample (the one not classified as a Broca’s aphasic). The rest were all non-fluent to various degrees, consistent with the diagnosis of Broca’s aphasia. We removed the fluent patient then grouped the rest in terms of their severity of non-fluency -- mild, moderate, severe -- and examined receptive speech abilities as a function of output fluency. If there is a relation between motor speech ability and speech perception, more severely non-fluent patients should perform more poorly on receptive speech tasks. There was no difference between groups (p-value = 0.39).
Thus, the stroke/aphasia literature is consistent with evidence from Wada studies, developmental anarthria studies, normal development studies, and animal studies of speech perception: the motor system is not necessary for speech perception.
D'Ausilio, A., Craighero, L., & Fadiga, L. (in press). The contribution of the frontal lobe to the perception of speech. Journal of Neurolinguistics. doi: 10.1016/j.jneuroling.2010.02.003
Hickok, G. (2010). The role of mirror neurons in speech perception and action word semantics. Language and Cognitive Processes, 25, 749 - 776.
Hickok, G., Costanzo, M., Capasso, R., & Miceli, G. (2011). The role of Broca’s area in speech perception: Evidence from aphasia revisited Brain and Language DOI: 10.1016/j.bandl.2011.08.001
Wilson, S. M., & Iacoboni, M. (2006). Neural responses to non-native phonemes varying in producibility: evidence for the sensorimotor nature of speech perception. Neuroimage, 33(1), 316-325.