Wheeldon, L. & Waksler, R. (2004). Phonological underspecification and mapping mechanisms in the speech recognition lexicon. Brain and Language, 90, 401–412.
Presentation: Sarah
Summary: Sally
Different models have been proposed for recognizing phonological variations in speech. Previous studies have shown that some variations are tolerated in speech processing, while others are not. Controversy has been found between the possibility of underspecification in lexical representations and the nature of mapping mechanism. This study was designed to test which of the two hypotheses better accounts for the tolerance of phonological mismatch in English. In total, 100 stimuli (combinations of un-/changed and in-/appropriate for both unspecified and specified conditions, plus a control group) were embedded in sentences as testing materials. A pretest was given to ensure all the stimuli were read with equal clarity. For the experiment, accuracy and reaction time data were collected from a perception task using a cross-modal repetition priming paradigm. Participants were asked to make a forced-choice decision between changed and unchanged versions of the stimuli. Results showed that for underspecified stimuli, RTs in all primed conditions were faster than the control conditions, but no significant difference was found among different primed conditions (e.g. Unchanged In-/appropriate: They heard there was a wicked ghost/prince in the castle. Changed Inappropriate: They heard there was a wickib ghost/prince in the castle.). However, for specified stimuli, in addition to the same general pattern that all primed conditions were faster than the control conditions, the Unchanged Appropriate condition (e.g. She never had franctic moments with the twins.) was also responded significantly faster than the Changed Inappropriate condition (e.g. She never had franctip days with the twins.). In other words, different patterns were observed between underspecified and specified stimuli, as segmental change did not affect the degree of priming effect of the former, but resulted in different degrees of the effect to the latter. Since [+coronal] is believed a universal default place feature, these results supported the model with underspecified mental lexicon and a context-independent mapping.
Different models have been proposed for recognizing phonological variations in speech. Previous studies have shown that some variations are tolerated in speech processing, while others are not. Controversy has been found between the possibility of underspecification in lexical representations and the nature of mapping mechanism. This study was designed to test which of the two hypotheses better accounts for the tolerance of phonological mismatch in English. In total, 100 stimuli (combinations of un-/changed and in-/appropriate for both unspecified and specified conditions, plus a control group) were embedded in sentences as testing materials. A pretest was given to ensure all the stimuli were read with equal clarity. For the experiment, accuracy and reaction time data were collected from a perception task using a cross-modal repetition priming paradigm. Participants were asked to make a forced-choice decision between changed and unchanged versions of the stimuli. Results showed that for underspecified stimuli, RTs in all primed conditions were faster than the control conditions, but no significant difference was found among different primed conditions (e.g. Unchanged In-/appropriate: They heard there was a wicked ghost/prince in the castle. Changed Inappropriate: They heard there was a wickib ghost/prince in the castle.). However, for specified stimuli, in addition to the same general pattern that all primed conditions were faster than the control conditions, the Unchanged Appropriate condition (e.g. She never had franctic moments with the twins.) was also responded significantly faster than the Changed Inappropriate condition (e.g. She never had franctip days with the twins.). In other words, different patterns were observed between underspecified and specified stimuli, as segmental change did not affect the degree of priming effect of the former, but resulted in different degrees of the effect to the latter. Since [+coronal] is believed a universal default place feature, these results supported the model with underspecified mental lexicon and a context-independent mapping.
