Dichotic Speech Recognition Using CVC Word and Nonsense CVC Syllable Stimuli

Abstract

Lexical content of stimulus materials impacts performance characteristics for dichotic speech recognition tasks in the normal-hearing young adult population. The use of nonsense CVC syllable material may provide a way to assess dichotic speech recognition performance while potentially lessening the effects of lexical content on performance.

The Filtered Words Test and the Influence of Lexicality

“…The present findings provide further support for the use of nonsense words in auditory processing tests as a way of assessing auditory processing without implicating the listener's lexical-semantic language abilities (Findlen & Roup, 2011). This also raises the possibility that the current use of real-word stimuli to assess auditory closure in persons with language impairments may inadvertently lead to the misdiagnosis of a comorbid APD (Dawes & Bishop, 2009) and inappropriate recommendations for treatment (Sharma et al, 2009).…”

“…The experimental stimuli were monosyllabic CVC real and nonsense words taken from Findlen and Roup (2011), whose stimuli were in turn based on Boothroyd and Nittrouer (1988). Although Findlen and Roup's 100 real words and 100 nonsense words had very similar phonetic content, they were not identical with respect to initial phonemes.…”

“…To investigate the utility of nonsense words in the assessment of auditory processing, Findlen and Roup (2011) compared the dichotic speech-recognition performance of healthy young adults for real-word CVC and nonsense-word CVC stimuli. Different real-word stimuli were presented to the participants' left and right ears with participants required to (a) repeat the stimuli in any order ( free recall), (b) repeat the stimuli heard in their left ear before their right (directed left), and (c) repeat the stimuli heard in their right ear before their left (directed right); these tasks were then repeated for the CVC nonsense-word stimuli.…”

The Effect of Lexical Content on Dichotic Speech Recognition in Older Adults

“…Speech recognition materials included 100 CVC words and 100 nonsense CVC syllables taken from stimulus lists developed by Boothroyd and Nittrouer (1988) and previously used in a similar investigation in a young adult population (Findlen and Roup, 2011). Although the original list from Boothroyd and Nittrouer contained 120 tokens in each list, some of the nonsense CVC syllables were judged to be actual words by a trained phonetician and were not used in the present study (e.g., /mal/ as mall, /kiz/ as keys).…”

“…This pattern of dichotic recognition performance is illustrated in Figure 1, which presents mean performance for CVCs (words and syllables) presented to the right and left ears as a function of response condition. Normative young adult data for the same tasks and stimuli from Findlen and Roup (2011) are presented for comparison purposes. Although the data in Figure 1 are not continuous, the right and left ear data points are connected by dotted lines for illustration purposes.…”