Neural mechanisms of abstract rule changes in speech : exploring phonologic and attentional constraints
Monte Ordoño, Julia · TDX (Tesis Doctorals en Xarxa) · 2018
The extraction of abstract rules from speech is paramount for language acquisition. The present dissertation explores the processing of linguistic rules by studying how our brain discovers the relevant abstract regularities in the signal. In order to tackle this question I followed three lines of research. First I focused on the detection of surface and structural changes of speech rules that I explored using an ERP approach. The objective was to understand the neural responses that are triggered after abstract rule violations in speech. Second, I studied the effects of the phoneme manipulations. The aim was to discover whether the ERP signatures linked to rule learning differ when the target regularity is implemented over consonants or over vowels. That is, I focused on exploring how different phonetic categories might trigger different neural responses to rule violations. And third, I explored the detection of rules from a heterogeneous context studying how abstract rules might be discovered over a noisy signal. Overall, the results we observed suggest that the manipulation of both the phonologic cues and the context of learning modulate the rule extraction process. More specifically, the present dissertation shows that both the task presented to the listeners and the phonemic cues present in the signal affect the selection of relevant sources of information from the speech. Even more, the experiments reported here show that the presence of a clear differentiating cue in the signal (such as the frequency unbalance across rules), might enhance the processing of different rule systems from the speech input.