What this means for learners
ASHUSLAY and Asmat share 10 sounds — roughly 36% of Asmat's inventory overlaps with ASHUSLAY. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 9 sounds found only in Asmat represent the greatest pronunciation challenge for ASHUSLAY speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, ASHUSLAY has 18 sounds not used in Asmat. Native Asmat speakers learning ASHUSLAY will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.