Adults quickly tune in to rhythm and melody of a new language, but early exposure to writing may hinder this skill

A new study led by Dr. Kateřina Chládková of the Faculty of Arts at Charles University reveals that adults can quickly tune in to the melodic and rhythmic features—known as prosody—of unfamiliar languages, but that premature exposure to writing may hinder this natural language-learning skill. The findings challenge current language-teaching practices and suggest adult learners might benefit more from listening-first approaches.

The research, published in the journal Bilingualism: Language and Cognition, tested whether adults could tune in to the sound of an unknown language following a brief exposure. 174 Czech-speaking adults listened to an unfamiliar language, Māori, for 5 minutes, and afterwards heard low-pass filtered clips of Māori and Malay, a very similar and also unfamiliar language to them.

Based on its melody and rhythm, participants successfully recognized Māori, evidencing a similar learning mechanism as that found in young infants tuning in to their native language.

Surprisingly, adults who were shown written transcriptions of the heard speech performed worse. The presence of orthography—especially such that was unfamiliar or non-transparent—hampered the listeners’ ability to sensitize to the melodic and rhythmic features of the exposed language.

Dr. Chládková explained the significance of these findings: “Our research suggests the adult brain is still highly capable of tuning in to new languages in a way similar to infants, provided that it’s not prematurely exposed to written forms. Orthography may block the brain’s ability to track and tune in to important prosodic cues, potentially hindering long-term proficiency in a second language.”

The researchers highlighted practical implications, suggesting that language educators might reconsider how and when they introduce written materials to new learners. “A more auditory-focused approach, especially in the earliest stages, could significantly improve the way adults learn new languages,” Dr. Chládková added.