The disclosure provides technology for enhancing the ability of a computing device to detect when a user has discontinued reading a text source. An example method includes receiving audio data comprising a spoken word associated with a text source, wherein the audio data comprises a first duration and a second duration; comparing the audio data with data of the text source, wherein the first duration of the audio data corresponds with the data of the text source; calculating, by a processing device, a correspondence measure between the second duration of the audio data and the data of the text source; and responsive to determining the correspondence measure satisfies a threshold, transmitting a signal to cease comparing audio data with the data of the text source.