Markers of group membership can be arbitrary, e.g., coloured vests, a flip of a coin, etc., or non-arbitrary, e.g., gender, language, race, etc.
[14] As such, a natural selection pressure may have existed that favoured social attention to accents, which functioned as an honesty signal (i.e., an honest signal of an individual's group membership), so individuals could easily identify in-group members from the potential threat of out-group members.
The affective processing approach proposes that the positive-bias exhibited for others who speak with an own-accent is produced by a (potentially unconscious) emotional reaction.
This theory has developed, and draws support, from neuroscientific research investigating affective prosody (a key component underlying accent) and vocal emotion, which has found activation (predominantly in the right hemisphere) in important brain regions associated with the processing of emotion.
[24][25] Therefore, these brain regions that deal with social relevance and vocal emotion are probable candidates for a neural network concerning accent-based group membership that would drive the affective processing of accents.
The prototype representation approach stems from theories developed in the linguistics and cognitive psychology domains.
It proposes that there are “prototypes” (i.e., internal representations) stored in the brain, which incoming information from the senses is compared against to facilitate categorisation.
[32] The authors of the study present similarities between the own-accent bias and the own-race bias, which states that faces are more easily recognised by people of the same race (own-race) because those people have more experience (higher expertise) with them compared to faces of different races (other-race).