To what extent can non-native pronunciation and perceptual patterns be described as a result of cue weighting transfer from the learners' L1?

Multiple studies directly testing the Cue-Weighting Transfer Hypothesis found that learners initially perceive L2 contrasts using the same relative balance of acoustic cues they use in their L1, even when that balance is not optimal for the L2 sound system.^4,5,8,13

Cue-weighting transfer shows up consistently whether the sound distinction involves consonants, vowels, lexical stress, tone, or larger phrase-level prosody, and across many different L1-L2 pairings (Korean-English, Mandarin-English, Japanese-English, Swedish-Japanese, Arabic-English, Chinese-English).^{1,2,3,4,5,8,9,10,13,19,23}

Where cue-weighting transfer has been tested carefully, learners' problems tend to be narrow and specific to the exact acoustic cue mismatched between L1 and L2, rather than a general inability to process the target language's sounds.¹

Transfer isn't limited to using the 'same' acoustic cue for the 'same' kind of contrast — a listening skill built around one L1 phonological feature (like lexical pitch accent) can help or hinder perception of an unrelated L2 feature (like stress) if the two rely on similar underlying cue-weighting strategies.⁵

As learners gain L2 proficiency or receive targeted phonetic training, their cue weights gradually shift toward the target-language pattern, but different cues shift at different rates and full native-like weighting is not always reached.^{3,4,6,8,10,18,21}

Deliberate training — including explicit rule-based instruction, high-variability phonetic training, and input manipulated to make the L1 cue unreliable — has been shown to shift learners' cue weighting toward native-like patterns, indicating the transferred weighting is not fixed.^6,18,20,21

Even within one L1 group learning the same L2 contrast, individual learners often show quite different cue-weighting strategies, and these individual patterns tend to be stable over time; L1 background sets a starting tendency but does not fully determine any one learner's pattern.^2,11,14,22

Cue-weighting transfer is not always L1-to-L2; extensive L2 experience can also reshape how bilinguals perceive or produce sounds in their native language, especially for immigrants and heritage speakers with a lot of L2 exposure.^7,15,17

When a learner's ability to perceive an L2 sound cue improves, their production of that same cue in speech tends to improve too, suggesting cue weighting is a shared mechanism linking listening and speaking skill rather than two separate problems.¹²

How harshly native or non-native listeners judge foreign-accented pronunciation depends partly on how familiar they are with that particular accent, which is thought to relate to their own L1 phonetic knowledge — but this is a separate, less direct piece of evidence than the direct cue-weighting experiments.¹⁶

Does cue-weighting transfer explain a 'foreign accent' completely, or are other factors involved?

The sources suggest cue-weighting transfer is an important but partial explanation. Deficits are often selective rather than global (learners can be fully native-like on some aspects of a sound system while struggling only with the specific cue mismatched between their L1 and the target language), and individual differences that aren't tied to L1 background at all — such as personal cue-weighting strategies that stay stable over months — also play a large role. So an accent is likely a mix of transferred L1 habits plus person-specific tendencies, rather than being explained by L1 transfer alone.