Detection of non-native speech in a familiar language and in an unfamiliar language

This study explores the question of whether native and non-native listeners, i.e. natives familiar with the language they are judging and non-natives who are not, manage to distinguish a foreign accent from a native accent in the speech of native speakers (NSs) and nonnative speakers (NNSs). Participants included 21 speakers (11 NSs and 10 NNSs who were native Turkish speakers) as well as two listener groups that consisted of 61 Finnish listeners (FLs), and 10 Turkish listeners (TLs) without Finnish experience. This study compares accent ratings by these two listener groups that evaluated the 21 spontaneous speech samples for foreign accent using a 9-point scale. The results showed a very significant difference between the listener groups for the NSs but no significant difference for the NNSs. The difference between the FL and the TL groups was because the FLs managed to distinguish the NSs from the NNSs, but otherwise these two listener groups exercised statistically similar ratings. Therefore, these results demonstrate that the listeners' familiarity with Finnish, the target language, hence listeners' native speaker status strongly affect ratings of foreign accents, since native listeners could distinguish the NSs, whereas non-native listeners could not. The results suggest that listeners' familiarity with the target language plays a much moreprofound role in accent detection than their familiarity with the accent language. Moreover, the results show that contrary to previous research, in the absence of listeners' familiarity with the target language, it is much more challenging to detect a foreign accent. The results also showed that speech rate correlated with the judgments provided by the TLs but not with the judgments provided by the FLs. This result raises the possibility that there are salient universal features of non-native speech such as speech rate that even non-native listeners unfamiliar with the language they are judging utilize while judging a foreign accent.