Adult Native Speakers Of English Research Articles

Semi-supervised Phonetic Category Learning: Does Word-level Information Enhance the Efficacy of Distributional Learning?

To test whether word-level information facilitates the learning of phonetic categories, 40 adult native English speakers were exposed to a bimodal distribution of vowels embedded in non-words. Half of the subjects received phonetic categories aligned with lexical categories, while the other half received no such cue. It was hypothesized that the subjects exposed to lexically-informative training stimuli that were aligned with the target categories would outperform the control subjects on a perceptual categorization task after training. While the results revealed no such group differences, the data indicated that many subjects used the relevant dimension for categorization before having received any training. Implications regarding experimental design and suggestions for future research based on the results are discussed.

The time course of morphological processing in a second language

We report findings from psycholinguistic experiments investigating the detailed timing of processing morphologically complex words by proficient adult second (L2) language learners of English in comparison to adult native (L1) speakers of English. The first study employed the masked priming technique to investigate - ed forms with a group of advanced Arabic-speaking learners of English. The results replicate previously found L1/L2 differences in morphological priming, even though in the present experiment an extra temporal delay was offered after the presentation of the prime words. The second study examined the timing of constraints against inflected forms inside derived words in English using the eye-movement monitoring technique and an additional acceptability judgment task with highly advanced Dutch L2 learners of English in comparison to adult L1 English controls. Whilst offline the L2 learners performed native-like, the eye-movement data showed that their online processing was not affected by the morphological constraint against regular plurals inside derived words in the same way as in native speakers. Taken together, these findings indicate that L2 learners are not just slower than native speakers in processing morphologically complex words, but that the L2 comprehension system employs real-time grammatical analysis (in this case, morphological information) less than the L1 system.

Relative Effects of Explicit and Implicit Feedback: The Role of Working Memory Capacity and Language Analytic Ability

The purpose of this study is to investigate the role of two cognitive factors (i.e. working memory capacity [WMC] and language analytic ability [LAA]) in the extent to which L2 learners benefit from two different types of feedback (i.e. explicit correction and recasts). Forty-eight adult native speakers of English, who had no previous exposure to the target language (i.e. Turkish), were randomly assigned into explicit correction, recast, and control (no feedback) groups. Learners performed two tasks with a native speaker of Turkish where their errors on two Turkish target structures (i.e. locative and plural) were treated according to their group assignment. Oral production, comprehension, and recognition tests were used to measure learners’ resulting performance. Learners’ WMC and LAA were measured with the operation span task (Turner and Engle 1989) and a subtest of the LLAMA Aptitude Tests (Meara 2005), respectively. Results showed that WMC and LAA moderated the effect of feedback group on both structures. Moreover, follow-up analyses revealed that explicit correction worked better than recasts only when the learners in the compared groups had high cognitive ability (high WMC or high LAA).

Word Learning in Adults With Second-Language Experience: Effects of Phonological and Referent Familiarity

The goal of this research was to examine whether phonological familiarity exerts different effects on novel word learning for familiar versus unfamiliar referents and whether successful word learning is associated with increased second-language experience. Eighty-one adult native English speakers with various levels of Spanish knowledge learned phonologically familiar novel words (constructed using English sounds) or phonologically unfamiliar novel words (constructed using non-English and non-Spanish sounds) in association with either familiar or unfamiliar referents. Retention was tested via a forced-choice recognition task. A median-split procedure identified high-ability and low-ability word learners in each condition, and the two groups were compared on measures of second-language experience. Findings suggest that the ability to accurately match newly learned novel names to their appropriate referents is facilitated by phonological familiarity only for familiar referents but not for unfamiliar referents. Moreover, more extensive second-language learning experience characterized superior learners primarily in one word-learning condition: in which phonologically unfamiliar novel words were paired with familiar referents. Together, these findings indicate that phonological familiarity facilitates novel word learning only for familiar referents and that experience with learning a second language may have a specific impact on novel vocabulary learning in adults.

Optimized speech sound category training bootstraps foreign word learning

The COmpetition between Verbal and Implicit Systems (COVIS) model posits multiple cognitive learning systems that are functionally distinct and compete with each other throughout learning. COVIS indicates two cognitive systems: a hypothesis-testing system mediated predominantly by the frontal cortex and a procedural-based system mediated by the striatum. Initial learning is dominated by the hypothesis-testing system, but with increased practice, control is passed to the procedural system. Importantly, each learning system can be optimized differentially to maximize performance. In this study, the COVIS model was applied to optimize Mandarin tone learning by adult native English speakers. The optimized category training (OCT) was designed to boost the hypothesis-testing system initially, then the procedural-based system subsequently. We then examined the extent to which OCT enhanced performance in a word learning task which required the participants to use their attained categories for Mandarin tones to disambiguate words. OCT was found to significantly enhance word learning relative to a control condition in which the learning systems were not optimized. These results demonstrate that a multiple systems approach can be used to develop optimized training protocols to maximally boost category learning.

Room acoustic effects on speech comprehension by English-as-a-second-language versus native English-speaking listeners

English-as-a-second-language (ESL) listeners are generally more impaired than native English-speaking listeners on speech intelligibility tasks under reverberation and noise; however, more study is needed to ascertain these groups’ performances on speech comprehension tasks, rather than intelligibility. A recent study (Valente et al, 2012) showed that speech comprehension by both native English-speaking adults and children was more negatively affected by adverse acoustic environments than sentence recognition. The current project investigates the speech comprehension of both ESL and native English-speaking adult listeners under combinations of reverberation and noise. Sets of 15-minute long listening comprehension tests based on the format of the Test of English for International Communication (TOEIC) were developed, anechoically recorded, convolved with binaural room impulse responses (BRIRs) to produce five mid-frequency reverberation times (0.4 to 1.1 seconds), and presented over loudspeakers in the Nebraska acoustics chamber. Background noise was also varied at three levels (RC-30, 40 and 50) through an Armstrong i-Ceiling system. In total then, subjects were individually exposed to 15 acoustic combinations of reverberation and background noise. Preliminary results will be presented and compared between ESL and native English listeners. [Work supported by a UNL Durham School Seed Grant and the Paul S. Veneklasen Research Foundation.]

Delayed feedback disrupts optimal strategies during foreign speech sound learning

The Competition between Verbal and Implicit Systems (COVIS) model posits that an explicit hypothesis-testing system competes with an implicit procedural-based system to mediate category learning. During early learning, the hypothesis-testing system is dominant, whereas in later learning, the procedural system dominates. In visual category learning, delayed feedback is known to impair the procedural but not the hypothesis-testing system. We tested the COVIS model in natural auditory category learning. Young adult native English speakers learned to categorize lexical tones in Mandarin syllables. Timing of feedback was either immediate (0 s) or delayed (500 or 1000 ms). Consistent with COVIS, delay feedback affected accuracy only in later learning. Further, modeling analysis revealed that participants were more likely to adopt procedural strategies during later learning, but this transition was disrupted by delayed feedback. These results will be discussed in the context of developing methods to optimize foreign speech sound learning.

The Relationship Between Expressive Vocabulary Knowledge and Reading Skills for Adult Struggling Readers.

This study examined expressive vocabulary and its relationship to reading skills for 232 native English-speaking adults who read between the third- and fifth-grade levels. The Boston Naming Test (BNT; Kaplan, Goodglass, & Weintraub, 2001) was used to measure expressive vocabulary. Participants scored lower than the normative sample of adults on all aspects of the test; they had fewer spontaneously correct answers, and were not helped by stimulus or phonemic cues. Hierarchical regression analyses revealed that expressive vocabulary accounted for significant variance in both reading comprehension and exception word reading, but not for general word reading or nonword reading.

Sensitivity to probabilistic orthographic cues to lexical stress in adolescent speakers with autism spectrum disorder and typical peers

Lexical stress refers to the opposition of strong and weak syllables within polysyllabic words and is a core feature of the English prosodic system. There are probabilistic cues to lexical stress present in English orthography. For example, most disyllabic English words ending with the letters "-ure" have first-syllable stress (e.g., "pasture", but note words such as "endure"), whereas most ending with "-ose" have second-syllable stress (e.g., "propose", but note examples such as "glucose"). Adult native speakers of English are sensitive to these probabilities during silent reading. During testing, they tend to assign first-syllable stress when reading a nonword such as "lenture" but second-syllable stress when reading "fostpose" (Arciuli & Cupples, 2006 ). Difficulties with prosody, including problems processing lexical stress, are a notable feature of autism spectrum disorder (ASD). The current study investigated the ability of adolescents with ASD (13-17 years of age) to show this sensitivity compared with a group of typically developing peers. Results indicated reduced sensitivity to probabilistic cues to lexical stress in the group with ASD. The implications of these findings are discussed.

When actions speak too much louder than words: Hand gestures disrupt word learning when phonetic demands are high

It is now widely accepted that hand gestures help people understand and learn language. Here, we provide an exception to this general rule—when phonetic demands are high, gesture actually hurts. Native English-speaking adults were instructed on the meaning of novel Japanese word pairs that were for non-native speakers phonetically hard (/ite/ vs. /itte/, which differ by only a geminate) or easy (/tate/ vs. /butta/, which differ by a geminate and also their segmental composition). The words were presented either with or without congruent iconic gestures, for example, “Ite means stay” (with a STAY gesture). After instruction, participants were given phonetic and vocabulary tests for the words they had learned. Although performance for the phonetic task was above chance for all conditions, gesture played different roles in the semantic task for easy and hard word pairs—it helped word learning for easy pairs, but it hurt for hard pairs. These results suggest that gesture and speech are semantically integrated during word learning, but only when phonetic demands are not too high.

The Availability of Universal Grammar to Second Language Learners: A Case of Wh-movement

In this experimental study, the researcher examined the accessibility of Universal Grammar to adult Persian learners of English with respect to the Empty Category Principle and the Subjacency. These principles are not operative in Persian as it is a Wh-in situ language. A 5-point Likert scale acceptability judgment task, which included both grammatical and ungrammatical extractions, was given to a group of 35 advanced Iranian EFL learners. The control group consisted of 30 adult native speakers of English. Their responses provided the baseline against which we measured the performance of non-native speakers. The categorical performance of natives and non-natives on both types of grammatical and ungrammatical extractions was revealed through within-group comparisons. Similarly, between-group comparisons displayed that the performance of Iranian EFL learners did not differ significantly from that of the natives in the ungrammatical constructions. In general, the findings of this study led the researcher to conclude that Universal Grammar constrains adult EFL learners’ competence.

Temporal transitions in narrative production with wordless picture books

We present empirical results that demonstrate temporal intervals in story time affect narrative structure. Eight native English-speaking adults estimated the duration of intervals between events depicted in consecutive pictures in Mercer and Marianna Mayer’s wordless picture books, and a separate group of 37 adults wrote stories to accompany these picture books. Analyses revealed that adults used significantly more temporal connectives (when, while, etc.) after long intervals than short ones. We argue that writers use temporal anchors to help readers update the temporal dimension of discourse representation, and that situation models (Zwaan, 1999) are relevant to narrative production.

Central nervous system markers for lexical tone learning

A large degree of individual variability can be observed in language learning in adulthood. This variability is especially prominent in the learning of foreign sounds, including lexical tones. In this presentation, I will report a series of experiments from my research group that examines the central nervous system markers for lexical tone learning success. Our knowledge such as collicular sensitivity to frequency modulation and cortical basis of pitch perception can begin to assist in generating specific hypotheses for these markers. In our experiments, native English-speaking adults learned Mandarin-like tone patterns in a lexical context. Behavioral, electrophysiological, neural hemodynamic (fMRI), and neuroanatomical measures were collected to characterize variability in learning success. Among the markers of success we found were integrity of the frequency following response, activity in the posterior auditory cortex, gray matter volume in the Heschl's Gyrus, and white matter connectivity within the auditory cortex. Some of these markers were used to redesign training in order to optimize learning for all learners, including training strategies such as enhancing auditory pitch cues and reducing trial-by-trial stimulus variability. Taken together, these experiments provide information regarding the neural basis of lexical tone learning and demonstrate the feasibility of using biomarkers for designing training. [Work supported by NIH and NSF]

Tornado Hazard Communication Disparities among Spanish-Speaking Individuals in an English-Speaking Community

The state of Oklahoma, known for destructive tornados, has a native Spanish-speaking (NSS) population of approximately 180,241, of which 50% report being able to speak English "very well" (US Census Bureau). With almost 50% of these native Spanish-speaking persons being limited English proficient (LEP), their reception of tornado hazard communications may be restricted. This study conducted in northeast Oklahoma (USA) evaluates the association between native language and receiving tornado hazard communications. This study was a cross-sectional survey conducted among a convenience sample of NSS and native English-speaking (NES) adults at Xavier Clinic and St. Francis Trauma Emergency Center in Tulsa, OK, USA from September 2009 through December 2009. Of the 82 surveys administered, 80 were returned, with 40 NES and 40 NSS participants. A scoring system (Severe Weather Information Reception (SWIR)) was developed to quantify reception of hazard information among the study participants (1-3 points=poor reception, 4-5=adequate reception, 6-8=excellent reception). Pearson's chi-squared test was used to calculate differences between groups with Yates' continuity correction applied where appropriate, and SWIR scores were analyzed using ANOVA. P-values<.05 were considered significant. NSS fluency in English was 25.6%. No significant association was found between native language and those who watch television, listen to radio, have a National Oceanic and Atmospheric Administration (NOAA) All Hazards radio or telephone, or are in audible range of a tornado siren. NSS were less likely to have Internet access (P<.004), and less likely to know of local telephone warning programs (P<.03). The mean NSS SWIR score was 3.2 (95% CI, 2.8-3.7) while LEP NSS averaged 2.8 (95% CI, 2.4-3.2). The mean NES SWIR score was 4.5 (95% CI, 4.1-5.0). Results demonstrate a disparity in tornado warning reception between NSS and NES. Poor English proficiency was noted to be 75% among NSS, which is approximately 25% more than estimated by the US Census Bureau. This study demonstrates a need for emergency managers to recognize when appropriate and overcome communication disparities among limited English proficient populations.

Rapid and multifaceted effects of second-language learning on first-language speech production

Despite abundant evidence of malleability in speech production, previous studies of the effects of late second-language learning on first-language speech production have been limited to advanced learners. This study examined these effects in novice learners, adult native English speakers enrolled in elementary Korean classes. In two acoustic studies, learners' production of English was found to be influenced by even brief experience with Korean. The effect was consistently one of assimilation to phonetic properties of Korean; moreover, it occurred at segmental, subsegmental, and global levels, often simultaneously. Taken together, the results suggest that cross-language linkages are established from the onset of second-language learning at multiple levels of phonological structure, allowing for pervasive influence of second-language experience on first-language representations. The findings are discussed with respect to current notions of cross-linguistic similarity, language development, and historical sound change.

Cortical systems that process language, as revealed by non-native speech sound perception

Over the course of language acquisition, the brain becomes specialized in the perception of native language speech sounds or phonemes. As a result, adult speakers are highly efficient at processing their native language, but may struggle to perceive some non-native phonemes. This specialization is thought to arise from changes that occur in a person's brain as a result of maturation and language experience. In this study, adult native speakers of English were asked to discriminate between phonemes of varying degrees of difference from English (similar to English: Tagalog /na/-/ŋa/; different from English: Ndebele /k||i/-/k!i/), as their brain activity was measured using functional near infrared spectroscopy imaging. The left inferior frontal region showed activation only during the native condition; this finding is discussed in the context of developmental and adult neuroimaging work and suggests that the left inferior frontal region is critical for perceiving native phoneme contrasts during development and in adulthood.

Researching Vocabulary: A Vocabulary Research Manual

Linguistic studies focusing on monolinguals have often examined individuals with considerable experience using another language. Results of a methodological review suggest that conflating ostensibly ‘multicompetent’ individuals with monolinguals is still common practice. A year-long longitudinal study of speech production demonstrates why this practice is problematic. Adult native English speakers recently arrived in Korea showed significant changes in their production of English stops and vowels (in terms of voice onset time, fundamental frequency, and formant frequencies) during Korean classes and continued to show altered English production a year later, months after their last Korean class. Consistent with an Incidental Processing Hypothesis (IPH) concerning the processing of ambient linguistic input, some changes persisted even in speakers who reported limited active use of Korean in their daily life. These patterns thus suggest that the linguistic experience obtained in a foreign language environment induces and then prolongs restructuring of the native language, making the multicompetent native speaker in a foreign language environment unrepresentative of a monolingual in a native language environment. Such restructuring supports the view that one’s native language continues to evolve in adulthood, highlighting the need for researchers to be explicit about a population under study and to accordingly control (and describe) language background in a study sample.

Second Language Learning Benefits from Similarity in Word Endings: Evidence from Russian

Diminutive derivations (e.g., froggy, bootie) constitute morphophonologically similar clusters of words in child‐directed speech and serve as low‐level schema for learning morphological regularities. Previous research has demonstrated that by regularizing noun endings, diminutives (e.g., Russian: domik, svechka) facilitate word‐boundary identification and the acquisition of inflectional morphology. In this study, adult native speakers of English (N = 77) were exposed to diminutive and simplex transparently gender‐marked nouns instantiating Russian case‐marking and adjective‐noun gender‐agreement patterns, over six 1‐hour language‐learning sessions. They were subsequently tested on their ability to extend grammatical patterns to new items and vocabulary recall. Learners showed equivalent learning of the trained phrases containing diminutive and simplex nouns but were more accurate in generalizing morphological patterns to diminutive nouns. Furthermore, learners showed a diminutive advantage in vocabulary retention. By increasing the invariant parts of words, diminutive derivations may reduce the amount of phonological material to be memorized and, subsequently, enhance word learning.

Phonological similarity influences word learning in adults learning Spanish as a foreign language

Neighborhood density-the number of words that sound similar to a given word (Luce & Pisoni, 1998)-influences word-learning in native English speaking children and adults (Storkel, 2004; Storkel, Armbruster, & Hogan, 2006): novel words with many similar sounding English words (i.e., dense neighborhood) are learned more quickly than novel words with few similar sounding English words (i.e., sparse neighborhood). The present study examined how neighborhood density influences word-learning in native English speaking adults learning Spanish as a foreign language. Students in their third-semester of Spanish language classes learned advanced Spanish words that sounded similar to many known Spanish words (i.e., dense neighborhood) or sounded similar to few known Spanish words (i.e., sparse neighborhood). In three word-learning tasks, performance was better for Spanish words with dense rather than sparse neighborhoods. These results suggest that a similar mechanism may be used to learn new words in a native and a foreign language.

Perception of Speech in Noise: Neural Correlates

The presence of irrelevant auditory information (other talkers, environmental noises) presents a major challenge to listening to speech. The fundamental frequency (F(0)) of the target speaker is thought to provide an important cue for the extraction of the speaker's voice from background noise, but little is known about the relationship between speech-in-noise (SIN) perceptual ability and neural encoding of the F(0). Motivated by recent findings that music and language experience enhance brainstem representation of sound, we examined the hypothesis that brainstem encoding of the F(0) is diminished to a greater degree by background noise in people with poorer perceptual abilities in noise. To this end, we measured speech-evoked auditory brainstem responses to /da/ in quiet and two multitalker babble conditions (two-talker and six-talker) in native English-speaking young adults who ranged in their ability to perceive and recall SIN. Listeners who were poorer performers on a standardized SIN measure demonstrated greater susceptibility to the degradative effects of noise on the neural encoding of the F(0). Particularly diminished was their phase-locked activity to the fundamental frequency in the portion of the syllable known to be most vulnerable to perceptual disruption (i.e., the formant transition period). Our findings suggest that the subcortical representation of the F(0) in noise contributes to the perception of speech in noisy conditions.