Automatic Auditory Processing of English Words as Indexed by the Mismatch Negativity, Using a Multiple Deviant Paradigm

Abstract

The results showed that MMN responses could be elicited by speech stimuli with large, single acoustic deviances, within a multiple deviant paradigm design. This result has positive clinical implications for the testing of subjects who may only tolerate short testing sessions (e.g., pathological populations) in that responses to a wider range of speech stimuli may be recorded without necessarily having to increase session length. The results also demonstrated that MMN responses were elicited by large, single acoustic deviances but not fine acoustic deviances within the speech stimuli. The poor results for the fine acoustic deviances support previous studies that have used single contrast paradigms and found that when carefully controlled methodological designs and strict methods of analysis are applied, robust responses to fine-grained CV syllable contrasts may be difficult to obtain. The enhanced MMN observed in response to the real word deviants among nonword standards may provide further evidence for the presence of long-term neural traces for words in the brain, however possible contextual effects limit the interpretation of these data. Further research is needed to investigate the ability of the MMN response to accurately reflect speech sounds with fine acoustic contrasts, as well as the ability of the MMN to reflect neural traces for words in the brain, before it can be reliably used as a clinical tool in the investigation of spoken word processing in pathological populations.

Towards neurophysiological assessment of phonemic discrimination: Context effects of the mismatch negativity

“…This means that a pitch difference, which is clearly perceivable, does not necessarily elicit an MMN. This is in contrast with what is often argued, namely, that an MMN arises to any discriminable contrast (Näätänen, 1995), but is in agreement with the findings by Pettigrew et al (2004), as well as what is argued by Bishop (2007), revealing that easily discriminable changes often do not elicit MMNs. It is striking that there is little literature about when and why discriminable contrasts do or do not elicit MMNs.…”

“…. Pettigrew et al, 2004). A great advantage of such a paradigm, as compared to the classical paradigm with one deviant stimulus, is that it does not require a lot of extra testing time, while more information about the quality of auditory discrimination can be obtained.…”

Attentional and linguistic interactions in speech perception

“…On the other hand, this conclusion seems to contradict findings from the ERP literature, specifically the MMN component elicited "pre-attentively" (i.e., without directed attention) in response to a phonemic change in an otherwise repetitive auditory stream (Endrass et al, 2004;Naatanen, 2001;Pettigrew et al, 2004;Pulvermuller & Shtyrov, 2006;Shtyrov et al, 2004). However, it is also known that the MMN can be susceptible to attentional manipulations, as its amplitude is attenuated when participants are engaged in a demanding primary task (e.g., Sabri et al, 2006;.…”

“…In a positron emission tomography (PET) study, Price and colleagues found activations associated with task-irrelevant visual word processing in the left posterior temporal lobe, the left inferior parietal lobe, the cuneus, and the left inferior frontal gyrus (IFG) when subjects were engaged in a nonlinguistic visual feature detection task (i.e., detection of one or more ascenders within word and nonword stimuli) (Price et al, 1996). Finally, event-related potential studies of the mismatch negativity (MMN) component provide evidence for detection of lexical or phonemic changes without directed attention to the auditory stream (Endrass et al, 2004;Naatanen, 2001;Pettigrew et al, 2004;Pulvermuller & Shtyrov, 2006;Pulvermuller et al, 2004;Shtyrov et al, 2004).…”

Verificação das respostas do mismatch negativity (MMN) em sujeitos adultos normais

“…Sittiprapaporn et al (2003) 11 concluded that MMN is more robust when triggered by speech sounds. Pettigrew et al (2004) 20 studied the MMN also with vocal stimulus. Such data was not found in our study, because the stimulus we used was tonal.…”