Presentations

Abstract

c

Abstract

c

Abstract

Recent empirical evidence suggests that language-mediated eye gaze around the visual world varies across individuals and is partly determined by their level of formal literacy training. Huettig, Singh & Mishra (2011) showed that unlike high-literate individuals, whose eye gaze was closely time locked to phonological overlap between a spoken target word and items presented in a visual display, low-literate individuals eye gaze was not tightly locked to phonological overlap in the speech signal but instead strongly influenced by semantic relationships between items. Our present study tests the hypothesis that this behaviour is an emergent property of an increased ability to extract phonological structure from the speech signal, as in the case of high-literates, with low-literates more reliant on syllabic structure. This hypothesis was tested using an emergent connectionist model, based on the Hub-and-spoke models of semantic processing (Dilkina et al, 2008), that integrates linguistic information extracted from the speech signal with visual and semantic information within a central resource. We demonstrate that contrasts in fixation behaviour similar to those observed between high and low literates emerge when the model is trained on either a speech signal segmented by phoneme (i.e. high-literates) or by syllable (i.e. low-literates).

Abstract

Sinking about boats and brains: activation of word meaning in foreign-accented speech by native and non-native listeners Andrea Weber, Meghan Sumner, Andrea Krott, Falk Huettig, Adriana Hanulikova Understanding foreign-accented speech requires from listeners the correct interpretation of segmental variation as in German-accented [s]eft for English theft. The task difficulty increases when the accented word forms resemble existing words as in [s]ink for think. In two English priming experiments, we investigated the activation of the meanings of intended and unintended words by accented primes. American native (L1) and German non-native (L2) participants listened to auditory primes followed by visual targets to which they made lexical decisions. Primes were produced by a native German speaker and were either nonsense words ([s]eft for theft), unintended words ([s]ink for think), or words in their canonical forms (salt for salt). Furthermore, primes were strongly associated to targets, with the co-occurrence being high either between the surface form of the prime and the target ([s]ink-BOAT, salt-PEPPER) or the underlying form and the target ([s]ink-BRAIN, seft-PRISON). L1 listeners responded faster when the underlying form was associated with the target (in comparison to unrelated primes), but L2 listeners responded faster when the surface form was associated. Seemingly, L1 listeners interpreted all primes as being mispronounced – facilitating the activation of think when hearing the unintended word [s]ink, but erroneously preventing the activation of salt when hearing the canonical form salt. L2 listeners, though, took primes at face value and failed to activate the meaning of think when hearing [s]ink but did activate the meaning of salt when hearing salt. This asymmetry suggests an interesting difference in the use of high-level information, with L1 listeners, but not L2 listeners, using knowledge about segmental variations for immediate meaning activation.

Abstract

A wealth of research has demonstrated that prediction is a core feature of human information processing. Much less is known, however, about the nature and the extent of predictive processing abilities. Here we investigated whether high levels of language expertise attained through formal literacy are related to anticipatory language-mediated visual orienting. Indian low and high literates listened to simple spoken sentences containing a target word (e.g., "door") while at the same time looking at a visual display of four objects (a target, i.e. the door, and three distractors). The spoken sentences were constructed to encourage anticipatory eye movements to visual target objects. High literates started to shift their eye gaze to the target object well before target word onset. In the low literacy group this shift of eye gaze occurred more than a second later, well after the onset of the target. Our findings suggest that formal literacy is crucial for the fine-tuning of language-mediated anticipatory mechanisms, abilities which proficient language users can then exploit for other cognitive activities such as language-mediated visual orienting.

Abstract

Eye movements made by listeners during language-mediated visual search reveal a strong link between visual processing and conceptual processing. For example, upon hearing the word for a missing referent with a characteristic colour (e.g., “strawberry”), listeners tend to fixate a colour-matched distractor (e.g., a red plane) more than a colour-mismatched distractor (e.g., a yellow plane). We ask whether these shifts in visual attention are mediated by the retrieval of lexically stored colour labels. Do children who do not yet possess verbal labels for the colour attribute that spoken and viewed objects have in common exhibit language-mediated eye movements like those made by older children and adults? That is, do toddlers look at a red plane when hearing “strawberry”? We observed that 24-month-olds lacking colour-term knowledge nonetheless recognised the perceptual-conceptual commonality between named and seen objects. This indicates that language-mediated visual search need not depend on stored labels for concepts.

Abstract

How do listeners recognize reduced forms that occur in spontaneous speech, such as “puter” for “computer”? To this end, eye-tracking experiments were performed in which participants heard a sentence and saw four printed words on a computer screen. The auditory stimuli contained canonical and reduced forms from a spontaneous speech corpus in different amounts of linguistic context. The four printed words were a “canonical form” competitor e.g., “companion”, phonologically similar to “computer”, a “reduced form” competitor e.g., “pupil”, phonologically similar to “puter” and two unrelated distractors. The results showed, first, that reduction inhibits word recognition overall. Second, listeners look more often to the “reduced form” competitor than to the “canonical form” competitor when reduced forms are presented in isolation or in a phonetic context. In full context, however, both competitors attracted looks: early rise of the “reduced form” competitor and late rise of the “canonical form” competitor. This “late rise” of the “canonical form” competitor was not observed when we replaced the original /p/ from “puter” with a real onset /p/. This indicates that phonetic detail and semantic/syntactic context are necessary for the recognition of reduced forms.

Abstract

Language processing does not take place in isolation from the sensory environment. Listeners are able to recognise spoken words in many different situations, ranging from carefully articulated and noise-free laboratory speech, through casual conversational speech in a quiet room, to degraded conversational speech in a busy train-station. For listeners to be able to recognize speech optimally in each of these listening situations, they must be able to adapt to the constraints of each situation. We investigated this flexibility by comparing the dynamics of the spoken-word recognition process in clear speech and speech disrupted by radio noise. In Experiment 1, Dutch participants listened to clearly articulated spoken Dutch sentences which each included a critical word while their eye movements to four visual objects presented on a computer screen were measured. There were two critical conditions. In the first, the objects included a cohort competitor (e.g., parachute, “parachute”) with the same onset as the critical spoken word (e.g., paraplu, “umbrella”) and three unrelated distractors. In the second condition, a rhyme competitor (e.g., hamer, “hammer”) of the critical word (e.g., kamer, “room”) was present in the display, again with three distractors. To maximize competitor effects pictures of the critical words themselves were not present in the displays on the experimental trials (e.g.,there was no umbrella in the display with the 'paraplu' sentence) and a passive listening task was used (Huettig McQueen, 2007). Experiment 2 was identical to Experiment 1 except that phonemes in the spoken sentences were replaced with radio-signal noises (as in AM radio listening conditions). In each sentence, two,three or four phonemes were replaced with noises. The sentential position of these replacements was unpredictable, but the adjustments were always made to onset phonemes. The critical words (and the immediately surrounding words) were not changed. The question was whether listeners could learn that, under these circumstances, onset information is less reliable. We predicted that participants would look less at the cohort competitors (the initial match to the competitor is less good) and more at the rhyme competitors (the initial mismatch is less bad). We observed a significant experiment by competitor type interaction. In Experiment 1 participants fixated both kinds competitors more than unrelated distractors, but there were more and earlier looks to cohort competitors than to rhyme competitors (Allopenna et al., 1998). In Experiment 2 participants still fixated cohort competitors more than rhyme competitors but the early cohort effect was reduced and the rhyme effect was stronger and occurred earlier. These results suggest that AM radio noise changes the dynamics of spoken word recognition. The well-attested finding of stronger reliance on word onset overlap in speech recognition appears to be due in part to the use of clear speech in most experiments. When onset information becomes less reliable, listeners appear to depend on it less. A core feature of the speech-recognition system thus appears to be its flexibility. Listeners are able to adjust the perceptual weight they assign to different parts of incoming spoken language.