Spectral and temporal degradation of speech as a simulation of morphosyntactic deficits in English and German

Abstract

Spectral and temporal degradation of the speech stream is increasingly used to model receptive language deficits such as aphasia and developmental language disorders. As with results from patient studies, the specific pattern of receptive deficits can reveal underlying structural and processing characteristics of different languages. Here, we test English-and German-speaking college studentsÕ auditory comprehension of complex morphosyntactic structures under normal and Ôdual-degradationÕ conditions. The resulting profiles of strength and vulnerability in the two languages highlight the cross-linguistic differences in reliability of syntactic and morphological cues, and closely resemble the deficits observed in previous studies of receptive aphasia.

Beyond the critical period: Processing-based explanations for poor grammaticality judgment performance by late second language learners

“…Previous studies have found that subject-verbobject word order was largely immune to memory load, noise or compressed speech stress (Blackwell & Bates, 1995;Dick et al, 2003;Dick et al, 2001;Waters et al, 2003); we found the same result. Previous studies have also found verb agreement to be quite vulnerable to these stressors (Blackwell & Bates, 1995;Dick et al, 2003;Kilborn, 1991); we found a significant decrease in third person singular subject verb agreement judgments in both the noise and compressed speech conditions. However, the current study also tested the effects of various stressors on several types of constructions that had not yet been examined.…”

“…However, it is also possible that these structures stand up better to processing stress. Indeed, in the studies of stressed native speakers cited above, stress did not seem to cause major problems for interpretation of canonical subject-verb-object sentences, be the stressor memory load, decoding difficulties or time limitations (Blackwell & Bates, 1995;Dick et al, 2001;Dick et al, 2003;Waters et al, 2003). Studies on stressed speakers have not tested the other constructions late L2 learners find easy; this will be remedied in the current study.…”

“…Compressed speech did not impact the interpretation of active and subject cleft structures, which follow standard subject-verb-object word order, but it did impact the interpretation passives and object clefts, which have non-canonical word order. Dick, Bates, and Ferstl (2003) examined the impact of a combination of compressed speech and low-pass filtering on use of word order (important in English) and agreement cues (important in German) in both English and German native speakers. The native English speakers showed no effect of degraded input on canonical word order sentences, but had poorer performance on non-canonical word orders with degraded speech.…”

“…But given this, many studies have found very poor performance by late L2 learners on determiners (Bialystok & Miller, 1999;Flege et al, 1999;Johnson & Newport, 1989;McDonald, 2000), and plurals (Bialystok & Miller, 1999;Flege et al, 1999;Johnson & Newport, 1989;McDonald, 2000), and some studies have found poor performance on past tense (Johnson & Newport, 1989), and agreement (verb agreement : Jiang, 2004;McDonald, 2000; gender agreement: Scherag et al, 2004). Studies of stressed native speakers also show difficulties with some of these structures-for example, verb agreement appears to be susceptible to stress of all three types (Blackwell & Bates, 1995;Dick et al, 2003;Kilborn, 1991), and number agreement (i.e., plurality) suffers under memory load stress (Blackwell & Bates, 1995).…”

“…Canonical word order seemed relatively immune to various stressors; non-canonical word order appeared to be vulnerable to stressors such as noise, low pass filtering and compressed speech (Dick et al, 2001). A few studies have investigated verb agreement and found this to generally be very vulnerable to memory, noise, and compressed speech stressors (Blackwell & Bates, 1995;Dick et al, 2003;Kilborn, 1991). In addition, some items in Bates and Blackwell (1995) examined number agreement between determiner and nouns (i.e., plurals), or omitted determiners.…”