Structural constraints in the perception of English stop-sonorant clusters

Native-language phonemes combined in a non-native way can be misperceived so as to conform to native phonotactics, e.g. English listeners are biased to hear syllable-initial [tr] rather than the illegal [tl] (Perception and Psychophysics 34 (1983) 338; Perception and Psychophysics 60 (1998) 941). What sort of linguistic knowledge causes phonotactic perceptual bias? Two classes of models were compared: unit models, which attribute bias to the listener's differing experience of each cluster (such as their different frequencies), and structure models, which use abstract phonological generalizations (such as a ban on [coronal][coronal] sequences). Listeners (N=16 in each experiment) judged synthetic 6 x 6 arrays of stop-sonorant clusters in which both consonants were ambiguous. The effect of the stop judgment on the log odds ratio of the sonorant judgment was assessed separately for each stimulus token to provide a stimulus-independent measure of bias. Experiment 1 compared perceptual bias against the onsets [bw] and [dl], which violate different structural constraints but are both of zero frequency. Experiment 2 compared bias against [dl] in CCV and VCCV contexts, to investigate the interaction of syllabification with segmentism and to rule out a compensation-for-coarticulation account of Experiment 1. Results of both experiments favor the structure models (supported by NSF).     

BIS/BAS responses to emotional cues: Self report, autonomic measure and alpha band modulation

The study explored the effect of the subjective evaluation and of BIS/BAS (Behavioral Inhibition and Activation System) differences on psychophysiological and brain oscillation measures, in response to pleasant/unpleasant and high/low arousing stimuli. Skin conductance response, heart rate, and electromyography, and alpha frequency band, were registered, during viewing IAPS figures. Both BIS and BAS measures were significant in modulating behavioral, autonomic and brain responses, with a clear dichotomy BAS-appetitive/positive BIS-withdrawal/negative sensitivity. Withdrawal (BIS) and appetitive (BAS) behavior showed opposite patterns of responses by the subjects within the frontal cortical site more than other sites. In addition, a specific frontal lateralization effect was found as a function of BIS (more right-side activation for negative cues) and BAS (more left-side activation for positive cues). Moreover, autonomic variables and frequency band were found to be effected by arousal rating per se, with an increased response to high arousal in comparison with low arousal and neutral stimuli. The effects of subjective evaluation and individual differences were discussed in the light of the coping activity of emotion comprehension.