How context affects perception: judging distress and linguistic content in forensic audio recordings

In order to assess the role of context on the perception of speech sounds, extracts of speech material from authentic forensic cases were played to two groups of listeners (experienced vs inexperienced forensic phoneticians) in two conditions (with and without sequential context). Listeners were asked to categorise each extract according to a four-way scale of perceptible distress and rate each extract according to a five-point scale of perceptible linguistic content. Findings show that extracts played without context are perceived as reflecting higher degrees of distress and lower levels of linguistic content. Experienced phoneticians performed more consistently as a group and were less prone to changing their responses across the two conditions.