Subtitles aren't just for foreign films. Over 100 studies show captions help everyone — and they're especially powerful for language learners.

The Research: 100+ Studies

A comprehensive review published in Policy Insights from the Behavioral and Brain Sciences examined over 100 empirical studies on video captions. The findings were clear: captioning a video improves comprehension of, attention to, and memory for the video — for children, adolescents, college students, and adults alike. (Gernsbacher, 2015)

The benefits aren't limited to any single group. Captions help:

Children learning to read: captions explicitly show the connection between spoken and written language
Adults improving literacy: studies in India showed dramatic literacy gains from captioned Bollywood music videos
Highly literate adults: college students remember course content better from captioned lectures
D/deaf and hard of hearing viewers: the original intended audience

Why Same-Language Subtitles Beat Translation

Here's the surprising part: for language learners, same-language subtitles (subtitles in the language being spoken) work better than subtitles in your native language.

A study of Japanese students learning English found that watching videos with English captions led to substantially better recall than watching with Japanese captions. In that experiment, Japanese captions performed no better than having no captions at all.

Why? When you read in your native language while listening to a foreign language, your brain essentially ignores the audio. But when both the audio and text are in your target language, your brain makes connections between the sounds and the written forms — reinforcing your learning.

Captions Improve Listening Comprehension

Another study at the University of Southern California tested ESL students on both written and listening comprehension. Students who watched videos with English captions performed better on both tests — even the listening test where no text was present.

This suggests that captions don't just help you understand what you're watching — they actively train your ear to recognize sounds and words in the target language.

It Works Across All Genres

The research shows captions benefit comprehension regardless of content type:

Documentaries
Dramas and films
Animations
Comedies
Music videos

Whatever content you enjoy watching, adding same-language subtitles will help you learn more from it.

The Problem: Not Everything Has Subtitles

Despite the benefits, many videos don't come with quality subtitles. Auto-generated captions on YouTube are often inaccurate. Local video files have nothing. That obscure podcast in your target language? No transcript.

This is exactly why SubSmith exists. You can generate accurate, editable subtitles for any video or audio file, in 99+ languages, all processed locally on your machine.

Want to turn your favorite shows into study material? Start with our guide on comprehensible input, then read our Whisper AI guide to generate captions locally. If you’re choosing a fast, practical setup, our Whisper versions compared (2026) breaks down the trade-offs.

FAQ

Do captions help native speakers? Yes—studies show better recall and attention even for fluent viewers.
Same-language or translated? For learning, same-language captions typically outperform translated ones because they reinforce listening and reading together.

The Takeaway

The science is clear: if you're learning a language, watch with same-language subtitles. It improves comprehension, builds vocabulary, and trains your listening skills — all at the same time.

Reference: Gernsbacher, M. A. (2015). Video Captions Benefit Everyone. Policy Insights from the Behavioral and Brain Sciences, 2(1), 195–202.