The video uses the terminology 'stammering'. Stuttering and stammering means exactly the same thing ([1](https://www.stuttering.co.nz/news/stuttering-vs-stammering-whats-the-difference/)) ([2](https://en.wikipedia.org/wiki/Stuttering)). Stuttering is used in the USA and stammering in the UK. So both words refer to the same, 'the speech blocks, repetitions and prolongations'