Chittin Chindaduangratn, Wichian Sittiprapaporn and Naiphinich Kotchabhakdi

pp. 773 - 778

Abstract

Event-related potential (ERP) responses to infrequently presented spoken deviant syllables /pi/ among
repetitive standard /pc/ syllables were recorded in Thai subjects who ignored these stimuli while reading
books of their choices. The vowel across-category changes elicited a change-specific mismatch negativity
response (MMN). The across-category change perception of vowels in consonant-vowel (CV) syllables was
also assessed using low-resolution electromagnetic tomography (LORETA). The LORETA-MMN generator
appeared in the left auditory cortex, emphasizing the role of the left hemisphere in speech processing already
at a preattentive processing level also in CV-syllables.

Keywords

• brain
• event-related potential (ERP)
• low-resolution electromagnetic tomography
  (LORETA)
• mismatch negativity (MMN)
• vowel
• categorical perception
• lateralization
• hemisphere
• speech