Publications

Abstract

The role of attentional control in lexical ambiguity resolution was examined in two patients with damage to the left inferior frontal gyrus (LIFG) and one control patient with non-LIFG damage. Experiment 1 confirmed that the LIFG patients had attentional control deficits compared to normal controls while the non-LIFG patient was relatively unimpaired. Experiment 2 showed that all three patients did as well as normal controls in using biasing sentence context to resolve lexical ambiguities involving balanced ambiguous words, but only the LIFG patients took an abnormally long time on lexical ambiguities that resolved toward a subordinate meaning of biased ambiguous words. Taken together, the results suggest that attentional control plays an important role in the resolution of certain lexical ambiguities – those that induce strong interference from context-inappropriate meanings (i.e., dominant meanings of biased ambiguous words).

Abstract

To highlight relevant information in dialogues, both wh-question context and pitch accent in answers can be used, such that focused information gains more attention and is processed more elaborately. To evaluate the relative influence of context and pitch accent on the depth of semantic processing, we measured Event-Related Potentials (ERPs) to auditorily presented wh-question-answer pairs. A semantically incongruent word in the answer occurred either in focus or non-focus position as determined by the context, and this word was either accented or unaccented. Semantic incongruency elicited different N400 effects in different conditions. The largest N400 effect was found when the question-marked focus was accented, while the other three conditions elicited smaller N400 effects. The results suggest that context and accentuation interact. Thus accented focused words were processed more deeply compared to conditions where focus and accentuation mismatched, or when the new information had no marking. In addition, there seems to be sex differences in the depth of semantic processing. For males, a significant N400 effect was observed only when the question-marked focus was accented, reduced N400 effects were found in the other dialogues. In contrast, females produced similar N400 effects in all the conditions. These results suggest that regardless of external cues, females tend to engage in more elaborate semantic processing compared to males.

Abstract

Genome-wide association study results have yielded evidence for the association of common genetic variants with crude measures of completed educational attainment in adults. Whilst informative, these results do not inform as to the mechanism of these effects or their presence at earlier ages and where educational performance is more routinely and more precisely assessed. Single nucleotide polymorphisms exhibiting genome-wide significant associations with adult educational attainment were combined to derive an unweighted allele score in 5,979 and 6,145 young participants from the Avon Longitudinal Study of Parents and Children with key stage 3 national curriculum test results (SATS results) available at age 13 to 14 years in English and mathematics respectively. Standardised (z-scored) results for English and mathematics showed an expected relationship with sex, with girls exhibiting an advantage over boys in English (0.433 SD (95%CI 0.395, 0.470), p<10-10) with more similar results (though in the opposite direction) in mathematics (0.042 SD (95%CI 0.004, 0.080), p = 0.030). Each additional adult educational attainment increasing allele was associated with 0.041 SD (95%CI 0.020, 0.063), p = 1.79×10-04 and 0.028 SD (95%CI 0.007, 0.050), p = 0.01 increases in standardised SATS score for English and mathematics respectively. Educational attainment is a complex multifactorial behavioural trait which has not had heritable contributions to it fully characterised. We were able to apply the results from a large study of adult educational attainment to a study of child exam performance marking events in the process of learning rather than realised adult end product. Our results support evidence for common, small genetic contributions to educational attainment, but also emphasise the likely lifecourse nature of this genetic effect. Results here also, by an alternative route, suggest that existing methods for child examination are able to recognise early life variation likely to be related to ultimate educational attainment.

Abstract

Twenty American English listeners identified gated fragments of all 2288 possible English within-word and cross-word diphones, providing a total of 538 560 phoneme categorizations. The results show orderly uptake of acoustic information in the signal and provide a view of where information about segments occurs in time. Information locus depends on each speech sound’s identity and phonological features. Affricates and diphthongs have highly localized information so that listeners’ perceptual accuracy rises during a confined time range. Stops and sonorants have more distributed and gradually appearing information. The identity and phonological features (e.g., vowel vs consonant) of the neighboring segment also influences when acoustic information about a segment is available. Stressed vowels are perceived significantly more accurately than unstressed vowels, but this effect is greater for lax vowels than for tense vowels or diphthongs. The dataset charts the availability of perceptual cues to segment identity across time for the full phoneme repertoire of English in all attested phonetic contexts.

Abstract

Two cross-modal priming studies investigated the recognition of English words spoken with a foreign accent. Auditory English primes were either typical of a Dutch accent or typical of a Japanese accent in English and were presented to both Dutch and Japanese L2 listeners. Lexical-decision times to subsequent visual target words revealed that foreign-accented words can facilitate word recognition for L2 listeners if at least one of two requirements is met: the foreign-accented production is in accordance with the language background of the L2 listener, or the foreign accent is perceptually confusable with the standard pronunciation for the L2 listener. If neither one of the requirements is met, no facilitatory effect of foreign accents on L2 word recognition is found. Taken together, these findings suggest that linguistic experience with a foreign accent affects the ability to recognize words carrying this accent, and there is furthermore a general benefit for L2 listeners for recognizing foreign-accented words that are perceptually confusable with the standard pronunciation.

Abstract

Two cross-modal priming experiments examined two questions about word recognition in foreign-accented speech: Does accent adaptation occur only for genuine accents markers, and does adaptation depend on language experience? We compared recognition of words spoken with canonical, genuinely-accented and arbitrarily-accented vowels. In Experiment 1, an Italian speaker pronounced vowels in English prime words canonically, or by lengthening /ɪ/ as in a genuine Italian accent (*/tri:k/ for trick), or by arbitrarily shortening /i:/ (*/trɪt/ for treat). Lexical-decision times to subsequent visual target words showed different priming effects in three listener groups. Monolingual native English listeners recognized variants with lengthened but not shortened vowels. Bilingual nonnative Italian-English listeners, who could not reliably distinguish vowel length, recognized both variants. Bilingual nonnative Dutch-English listeners also recognized both variants. In Experiment 2, bilingual Dutch-English listeners recognized Dutch words with genuinely- and arbitrarily-accented vowels (spoken by a native Italian with lengthened and shortened vowels respectively), but recognized words with canonical vowels more easily than words with accented vowels. These results suggest that adaptation to genuine accent markers arises for monolingual and bilingual listeners alike and can occur in native and nonnative languages, but that bilinguals can adapt to arbitrary accent markers better than monolinguals.

Abstract

Humans differ widely in their navigational abilities. Studies have shown that self-reports on navigational abilities are good predictors of performance on navigation tasks in real and virtual environments. The caudate nucleus and medial temporal lobe regions have been suggested to subserve different navigational strategies. The ability to use different strategies might underlie navigational ability differences. This study examines the anatomical correlates of self-reported navigational ability in both gray and white matter. Local gray matter volume was compared between a group (N = 134) of good and bad navigators using voxel-based morphometry (VBM), as well as regional volumes. To compare between good and bad navigators, we also measured white matter anatomy using diffusion tensor imaging (DTI) and looked at fractional anisotropy (FA) values. We observed a trend toward higher local GM volume in right anterior parahippocampal/rhinal cortex for good versus bad navigators. Good male navigators showed significantly higher local GM volume in right hippocampus than bad male navigators. Conversely, bad navigators showed increased FA values in the internal capsule, the white matter bundle closest to the caudate nucleus and a trend toward higher local GM volume in the caudate nucleus. Furthermore, caudate nucleus regional volume correlated negatively with navigational ability. These convergent findings across imaging modalities are in line with findings showing that the caudate nucleus and the medial temporal lobes are involved in different wayfinding strategies. Our study is the first to show a link between self-reported large-scale navigational abilities and different measures of brain anatomy.

Abstract

Early language development is known to be under genetic influence, but the genes affecting normal variation in the general population remain largely elusive. Recent studies of disorder reported that variants of the CNTNAP2 gene are associated both with language deficits in specific language impairment (SLI) and with language delays in autism. We tested the hypothesis that these CNTNAP2 variants affect communicative behavior, measured at 2 years of age in a large epidemiological sample, the Western Australian Pregnancy Cohort (Raine) Study. Singlepoint analyses of 1149 children (606 males, 543 emales) revealed patterns of association which were strikingly reminiscent of those observed in previous investigations of impaired language, centered on the same genetic markers, and with a consistent direction of effect (rs2710102, p = .0239; rs759178, p = .0248). Based on these findings we performed analyses of four-marker haplotypes of rs2710102- s759178-rs17236239-rs2538976, and identified significant association (haplotype TTAA, p = .049; haplotype GCAG, p = .0014). Our study suggests that common variants in the exon 13-15 region of CNTNAP2 influence early language acquisition, as assessed at age 2, in the general population. We propose that these CNTNAP2 variants increase susceptibility to SLI or autism when they occur together with other risk factors.

Abstract

Studies on metacognition have shown that participants can report on their performance on a wide range of perceptual, memory and behavioral tasks. We know little, however, about the ability to report on one's attentional focus. The degree and direction of somatosensory attention can, however, be readily discerned through suppression of alpha band frequencies in EEG/MEG produced by the somatosensory cortex. Such top-down attentional modulations of cortical excitability have been shown to result in better discrimination performance and decreased response times. In this study we asked whether the degree of attentional focus is also accessible for subjective report, and whether such evaluations correspond to the amount of somatosensory alpha activity. In response to auditory cues participants maintained somatosensory attention to either their left or right hand for intervals varying randomly between 5 and 32seconds, while their brain activity was recorded with MEG. Trials were terminated by a probe sound, to which they reported their level of attention on the cued hand right before probe-onset. Using a beamformer approach, we quantified the alpha activity in left and right somatosensory regions, one second before the probe. Alpha activity from contra- and ipsilateral somatosensory cortices for high versus low attention trials were compared. As predicted, the contralateral somatosensory alpha depression correlated with higher reported attentional focus. Finally, alpha activity two to three seconds before the probe-onset was correlated with attentional focus. We conclude that somatosensory attention is indeed accessible to metacognitive awareness.

Abstract

Does language comprehension depend, in part, on neural systems for action? In previous studies, motor areas of the brain were activated when people read or listened to action verbs, but it remains unclear whether such activation is functionally relevant for comprehension. In the experiments reported here, we used off-line theta-burst transcranial magnetic stimulation to investigate whether a causal relationship exists between activity in premotor cortex and action-language understanding. Right-handed participants completed a lexical decision task, in which they read verbs describing manual actions typically performed with the dominant hand (e.g., “to throw,” “to write”) and verbs describing nonmanual actions (e.g., “to earn,” “to wander”). Responses to manual-action verbs (but not to nonmanual-action verbs) were faster after stimulation of the hand area in left premotor cortex than after stimulation of the hand area in right premotor cortex. These results suggest that premotor cortex has a functional role in action-language understanding.

Abstract

We investigated how visual and linguistic information interact in the perception of emotion. We borrowed a phenomenon from film theory which states that presentation of an as such neutral visual scene intensifies the percept of fear or suspense induced by a different channel of information, such as language. Our main aim was to investigate how neutral visual scenes can enhance responses to fearful language content in parts of the brain involved in the perception of emotion. Healthy participants’ brain activity was measured (using functional magnetic resonance imaging) while they read fearful and less fearful sentences presented with or without a neutral visual scene. The main idea is that the visual scenes intensify the fearful content of the language by subtly implying and concretizing what is described in the sentence. Activation levels in the right anterior temporal pole were selectively increased when a neutral visual scene was paired with a fearful sentence, compared to reading the sentence alone, as well as to reading of non-fearful sentences presented with the same neutral scene. We conclude that the right anterior temporal pole serves a binding function of emotional information across domains such as visual and linguistic information.

Abstract

A debated issue in the relationship between language and thought is how our linguistic abilities are involved in understanding the intentions of others (‘mentalizing’). The results of both theoretical and empirical work have been used to argue that linguistic, and more specifically, grammatical, abilities are crucial in representing the mental states of others. Here we contribute to this debate by investigating how damage to the language system influences the generation and understanding of intentional communicative behaviors. Four patients with pervasive language difficulties (severe global or agrammatic aphasia) engaged in an experimentally controlled non-verbal communication paradigm, which required signaling and understanding a communicative message. Despite their profound language problems they were able to engage in recipient design as well as intention recognition, showing similar indicators of mentalizing as have been observed in the neurologically healthy population. Our results show that aspects of the ability to communicate remain present even when core capacities of the language system are dysfunctional

Abstract

Do people use sensori-motor cortices to understand language? Here we review neurocognitive studies of language comprehension in healthy adults and evaluate their possible contributions to theories of language in the brain. We start by sketching the minimal predictions that an embodied theory of language understanding makes for empirical research, and then survey studies that have been offered as evidence for embodied semantic representations. We explore four debated issues: first, does activation of sensori-motor cortices during action language understanding imply that action semantics relies on mirror neurons? Second, what is the evidence that activity in sensori-motor cortices plays a functional role in understanding language? Third, to what extent do responses in perceptual and motor areas depend on the linguistic and extra-linguistic context? And finally, can embodied theories accommodate language about abstract concepts? Based on the available evidence, we conclude that sensori-motor cortices are activated during a variety of language comprehension tasks, for both concrete and abstract language. Yet, this activity depends on the context in which perception and action words are encountered. Although modality-specific cortical activity is not a sine qua non of language processing even for language about perception and action, sensori-motor regions of the brain appear to make functional contributions to the construction of meaning, and should therefore be incorporated into models of the neurocognitive architecture of language.

Abstract

Left-handers are often excluded from study cohorts in neuroscience and neurogenetics in order to reduce variance in the data. However, recent investigations have shown that the inclusion or targeted recruitment of left-handers can be informative in studies on a range of topics, such as cerebral lateralization and the genetic underpinning of asymmetrical brain development. Left-handed individuals represent a substantial portion of the human population and therefore left-handedness falls within the normal range of human diversity; thus, it is important to account for this variation in our understanding of brain functioning. We call for neuroscientists and neurogeneticists to recognize the potential of studying this often-discarded group of research subjects.

Abstract

Marr and Poggio’s levels of description are one of the most well-known theoretical constructs of twentieth century cognitive science. It entails that behavior can and should be considered at three different levels: computation, algorithm, and implementation. In this contribution focus is on the computational level of description, the level that describes the “why” of cognition. I argue that the computational level should be taken as a starting point in devising experiments in cognitive (neuro)science. Instead, the starting point in empirical practice often is a focus on the stimulus or on some capacity of the cognitive system. The “why” of cognition tends to be ignored when designing research, and is not considered in subsequent inference from experimental results. The overall aim of this manuscript is to show how re-appreciation of the computational level of description as a starting point for experiments can lead to more informative experimentation.

Abstract

While most people prefer to use their right hand to brush their teeth, throw a ball, or hold a tennis racket, left-handers prefer to use their left hand. This is the case for around 10 per cent of all people. There was a time (not so long ago) when left-handers were stigmatized in Western (and other) communities: it was considered a bad sign if you were left-handed, and left-handed children were often forced to write with their right hand. This is nonsensical: there is nothing wrong with being left-handed, and trying to write with the non-preferred hand is frustrating for almost everybody. As a matter of fact, science can learn from left-handers, and in this paper, we discuss how this may be the case. We review why some people are left-handed and others are not, how left-handers' brains differ from right-handers’, and why scientists study left-handedness in the first place

Abstract

Are listeners able to adapt to a foreign-accented speaker who has, as is often the case, an inconsistent accent? Two groups of native Dutch listeners participated in a cross-modal priming experiment, either in a consistent-accent condition (German-accented items only) or in an inconsistent-accent condition (German-accented and nativelike pronunciations intermixed). The experimental words were identical for both groups (words with vowel substitutions characteristic of German-accented speech); additional contextual words differed in accentedness (German-accented or nativelike words). All items were spoken by the same speaker: a German native who could produce the accented forms but could also pass for a Dutch native speaker. Listeners in the consistent-accent group were able to adapt quickly to the speaker (i.e., showed facilitatory priming for words with vocalic substitutions). Listeners in the inconsistent-accent condition showed adaptation to words with vocalic substitutions only in the second half of the experiment. These results indicate that adaptation to foreign-accented speech is rapid. Accent inconsistency slows listeners down initially, but a short period of additional exposure is enough for them to adapt to the speaker. Listeners can therefore tolerate inconsistency in foreign-accented speech.

Abstract

It is widely believed that human languages cannot encode odors. While this is true for English,
and other related languages, data from some non-Western languages challenge this
view. Maniq, a language spoken by a small population of nomadic hunter–gatherers in
southern Thailand, is such a language. It has a lexicon of over a dozen terms dedicated
to smell. We examined the semantics of these smell terms in 3 experiments (exemplar
listing, similarity judgment and off-line rating). The exemplar listing task confirmed that
Maniq smell terms have complex meanings encoding smell qualities. Analyses of the
similarity data revealed that the odor lexicon is coherently structured by two dimensions.
The underlying dimensions are pleasantness and dangerousness, as verified by the off-line
rating study. Ethnographic data illustrate that smell terms have detailed semantics tapping
into broader cultural constructs. Contrary to the widespread view that languages cannot
encode odors, the Maniq data show odor can be a coherent semantic domain, thus shedding
new light on the limits of language.

Abstract

Neural structures change with age but there is no consensus on the exact processes involved. This study tested the hypothesis that white and grey matter in the language network changes during aging according to a “last in, first out” process. The fractional anisotropy (FA) of white matter and cortical thickness of grey matter were measured in 36 participants whose ages ranged from 55 to 79 years. Within the language network, the dorsal pathway connecting the mid-to-posterior superior temporal cortex (STC) and the inferior frontal cortex (IFC) was affected more by aging in both FA and thickness than the other dorsal pathway connecting the STC with the premotor cortex and the ventral pathway connecting the mid-to-anterior STC with the ventral IFC. These results were independently validated in a second group of 20 participants whose ages ranged from 50 to 73 years. The pathway that is most affected during aging matures later than the other two pathways (which are present at birth). The results are interpreted as showing that the neural structures which mature later are affected more than those that mature earlier, supporting the “last in, first out” theory.

Abstract

For most people, speech production is relatively effortless and error-free. Yet it has long been recognized that we need some type of control over what we are currently saying and what we plan to say. Precisely how we monitor our internal and external speech has been a topic of research interest for several decades. The predominant approach in psycholinguistics has assumed monitoring of both is accomplished via systems responsible for comprehending others' speech.

This special topic aimed to broaden the field, firstly by examining proposals that speech production might also engage more general systems, such as those involved in action monitoring. A second aim was to examine proposals for a production-specific, internal monitor. Both aims require that we also specify the nature of the representations subject to monitoring.

Abstract

Given the limited processing capabilities of the sensory system, it is essential that attended information is gated to downstream areas, whereas unattended information is blocked. While it has been proposed that alpha band (8–13 Hz) activity serves to route information to downstream regions by inhibiting neuronal processing in task-irrelevant regions, this hypothesis remains untested. Here we investigate how neuronal oscillations detected by electroencephalography in visual areas during working memory encoding serve to gate information reflected in the simultaneously recorded blood-oxygenation-level-dependent (BOLD) signals recorded by functional magnetic resonance imaging in downstream ventral regions. We used a paradigm in which 16 participants were presented with faces and landscapes in the right and left hemifields; one hemifield was attended and the other unattended. We observed that decreased alpha power contralateral to the attended object predicted the BOLD signal representing the attended object in ventral object-selective regions. Furthermore, increased alpha power ipsilateral to the attended object predicted a decrease in the BOLD signal representing the unattended object. We also found that the BOLD signal in the dorsal attention network inversely correlated with visual alpha power. This is the first demonstration, to our knowledge, that oscillations in the alpha band are implicated in the gating of information from the visual cortex to the ventral stream, as reflected in the representationally specific BOLD signal. This link of sensory alpha to downstream activity provides a neurophysiological substrate for the mechanism of selective attention during stimulus processing, which not only boosts the attended information but also suppresses distraction. Although previous studies have shown a relation between the BOLD signal from the dorsal attention network and the alpha band at rest, we demonstrate such a relation during a visuospatial task, indicating that the dorsal attention network exercises top-down control of visual alpha activity.

Abstract

Review: User friendliness of the first dictionary of Sign Language of the Netherlands can be improved

Abstract

(Needed: staff for residential care home with good eye-hand coordination. Measuring NGT-skills.)

Abstract

(The Corpus NGT and the daily practice of language teaching)

Abstract

(The Corpus NGT and teacher NGT/interpreter NGT training)