While most foreign language courses try hard to provide native speakers, a new study shows that adults find it easier when the teacher speaks it in the same accent as the student. 60 participants aged 18-26, of whom 20 were native Hebrew speakers, 20 new adult immigrants to Israel from the Former Soviet Union, and 20 were Israeli Arabic speakers who began learning Hebrew at age 7-8, has found that while accent made no difference to native Hebrew speakers, both the Russian and Arabic speakers needed less phonological information to recognize Hebrew words when they were pronounced in the accent of their native language.
(2009). Listening with an Accent: Speech Perception in a Second Language by Late Bilinguals.
Journal of Psycholinguistic Research. 38(5), 447 - 457.