Use of short podcasts to reinforce learning outcomes in biology.

Podcasts are audio or video files which can be automatically downloaded to one’s computer when the episodes become available, then later transferred to a portable player for listening. The technology thereby enables the user to listen to and/or watch the content anywhere at any time. Formerly popular as radio shows, podcasting was rapidly explored and used in different areas and with several purposes, due to the facility of its production, editing, and distribution. Higher education was no exception and several universities around the world, aware of the audio power of easy online access, have been stimulating the use of podcasts [1–4]. Most of the studies have been using audio files [5–7] but video files (vodcasts or vidcasts) or a record with images (enhanced podcast) can also be produced. Another type of podcast is a screen capture with a recorded voice (screencast) generally used for demonstrating a task or tutorial on a computer screen. Some authors claim that it is a renaissance of audio for learning, though digital audio content would never replace reading, listening to live presentations, or the multitude of other ways of obtaining information [2, 6, 8]. Audio can effectively be a great way to deliver information especially for auditory learners [8, 9] and the possibility to stop, start, and replay makes it very appropriate for students with special needs or different learning paces. According to several authors [2, 6, 10, 11] audio can have pedagogical advantages because the spoken word can influence both cognition and motivation. Furthermore, voice is personal and its frequencies allow the adjustment of intonation, inflection, phrasing, pacing, volume, loudness, and timbre. In higher education, podcasts may be created for several purposes such as vocabulary revision, listening exercises, interviews with native speakers, summaries of a lecture or lectures, describing homework assignments, giving feedback, guidelines, reducing the effects of isolation, promoting inclusivity, developing students’ study skills through collaborative learning, providing guidance, and so on [1, 5–7, 12–14]. Also, podcasting has been proposed as a way of changing teacher practices and to motivate students through innovation [2, 6, 8]. Several recommendations should be followed when producing podcasts. Podcast length should undoubtedly be related to its content and purpose. However, to avoid the loss of attention in listening, a general rule would be to produce short podcasts [5–7], around 1 to 5 min length [15]. Podcasts should have technical quality, being important to produce episodes free of background noise, tinny-sounding, and verbal mistakes that interrupt the flow of the podcast. It is also important to engage listeners and keep their attention through the entire episode, preferably by keeping podcasts short and simple, clear and concise, lively and entertaining [5, 16, 17].