Quantifying children's sensorimotor experience: Child body-object interaction ratings for 3,359 English words

Body-object interaction (BOI) ratings measure how easily the human body can physically interact with a word's referent. Previous research has found that words higher in BOI tend to be processed more quickly and accurately in tasks such as lexical decision, semantic decision, and syntactic classification, suggesting that sensorimotor information is an important aspect of lexical knowledge. However, limited research has examined the importance of sensorimotor information from a developmental perspective. One barrier to addressing such theoretical questions has been a lack of semantic dimension ratings that take into account child sensorimotor experience. The goal of the current study was to collect Child BOI rating norms. Parents of children aged 5 – 9-years-old were asked to rate words according to how easily an average 6-year-old child can interact with each word’s referent. The relationships of Child and Adult BOI ratings with other lexical semantic dimensions were assessed, as well as the relationships of Child and Adult BOI ratings with age of acquisition. Child BOI ratings were more strongly related to valence and sensory experience ratings than Adult BOI ratings and were a better predictor of three different measures of age of acquisition. The results suggest that child-centric ratings such as those reported here provide a more sensitive measure of children’s experience that can be used to address theoretical questions in embodied cognition from a developmental perspective.

Testing the perilesional neuroplastic recruitment hypothesis in aphasia

Objective: A prominent theory proposes that neuroplastic recruitment of perilesional tissue supports aphasia recovery, especially when language-capable cortex is spared by smaller lesions. This theory has rarely been tested directly, and findings have been inconclusive. Here, we test the perilesional plasticity hypothesis using two fMRI tasks in two groups of stroke survivors. Methods: Two cohorts totaling 84 chronic left-hemisphere stroke survivors with prior aphasia diagnosis, and 80 control participants underwent fMRI using either a naming task or a reliable semantic decision task. Individualized perilesional tissue was defined by dilating anatomical lesions, and language regions were defined using meta-analyses. Mixed modeling examined differences in activity between groups. Relationships with lesion size and aphasia severity were examined. Results: Stroke survivors exhibited reduced activity in perilesional language tissue relative to controls in both tasks. Although a few cortical regions exhibited greater activity irrespective of distance from the lesion, or only when distant from the lesion, no regions exhibited increased activity only when near the lesion. Larger lesions were associated with reduced language activity irrespective of distance from the lesion. Using the reliable fMRI task, reduced language activity related to aphasia severity independent of lesion size. Interpretation: We find no evidence for neuroplastic recruitment of perilesional tissue in aphasia beyond its typical role in language. Rather, our findings are consistent with alternative hypotheses that left-hemisphere activation changes during recovery relate to normalization of language network dysfunction and possibly recruitment of alternate cortical processors. These findings clarify left-hemisphere neuroplastic mechanisms supporting language recovery after stroke.

Electrophysiological insights into the role of proficiency in bilingual novel and conventional metaphor processing

While novel and conventional metaphor comprehension has received much attention in the monolingual context, thus far little electrophysiological research has been conducted with a view to examining how bilingual speakers process metaphors in their non-native language (L2) as well as how L2 proficiency level might modulate such processes. The present study aims to investigate the electrophysiological correlates of novel and conventional metaphor comprehension in intermediate and advanced Chinese-English bilingual speakers. The participants performed a semantic decision task to English (L2) novel metaphoric, conventional metaphoric, literal, and anomalous word pairs. The results showed a graded N400 effect from literal utterances, to conventional metaphors, novel metaphors, and finally to anomalous utterances in both groups of participants, indicating that both types of metaphors were more cognitively taxing than literal utterances, irrespectively of L2 proficiency level. Additionally, between-group differences that were irrespective of utterance type were found in the N400 time frame, indicating more extended lexico-semantic access in the intermediate relative to the advanced group. Finally, in both groups of participants, an anterior sustained negativity was found in response to anomalous, novel metaphoric, and conventional metaphoric word pairs, thus suggesting a continuing difficulty of meaning integration.

Influence of Manner Adverbs on Action Verb Processing

Language-motor interaction is suggested by the involvement of motor areas in action-related language processing. In a double-dissociation paradigm we aimed to investigate motor cortical involvement in the processing of hand- and foot-related action verbs combined with manner adverbs. In two experiments using different tasks, subjects were instructed to respond with their hand or foot following the presentation of an adverb-verb combination. Experiment 1, which prompted reactions via color changes of the stimuli combined with a semantic decision, showed an influence of manner adverbs on response times. This was visible in faster responses following intensifying adverbs compared with attenuating adverbs. Additionally, an interaction between implied verb effector and response effector manifested in faster response times for matching verb-response conditions. Experiment 2, which prompted reactions directly by the adverb type (intensifying vs. attenuating), revealed an interaction between manner adverbs and response effector with faster hand responses following intensifying compared with attenuating adverbs. Additional electroencephalography (EEG) recordings in Experiment 2 revealed reduced beta-desynchronization for congruent verb-response conditions in the case of foot responses along with faster response times. Yet, a direct modulation of verb-motor priming by adverbs was not found. Taken together, our results indicate an influence of manner adverbs on the interplay of language processing and motor behavior. Results are discussed with respect to embodied cognition theories.

Mechanisms of Different Types of Figurative Expressions Processing

Modern models of figurative language processing postulate that figurative expressions (FE), e.g. metaphors, are processed through inclusion of one FE component to the category of another. However, some FE can simply be understood by finding commonalities between FE components. This way of processing is better explained by the early semantic network model, on which modern models of figurative language processing are based. The current study attempts to reveal capabilities of categorization approach and semantic network model to explain mechanisms of different FE processing. Subjects (N=67) performed semantic decision tasks, which required answering the question whether the meaning of the presented adjective corresponds to the meaning of an adjective in the context of an expression presented earlier. The results of reaction time analysis suggest that categorization approach is not exhaustive for the explanation of figurative language processing and some of the effects might be explained in terms of the semantic network model. This indicates that it is necessary to include some semantic network model postulates into modern approaches of figurative language comprehension.

Inconsistent lateralisation of language functions: a risk factor for language impairment?

Disruption to language lateralisation has been proposed as a cause of developmental language impairments. In this study we tested the idea that consistency of lateralisation across different language functions is associated with language ability. A large sample of adults with variable language abilities (N=67 with a developmental disorder affecting language and N=37 controls) were recruited. Lateralisation was measured using functional transcranial Doppler sonography (fTCD) for three language tasks that engage different language sub-processes (phonological decision, semantic decision and sentence generation). The whole sample was divided into those with consistent versus inconsistent lateralisation across the three tasks. Language ability (using a battery of standardised tests) was compared between the consistent and inconsistent groups. The results did not show a significant effect of lateralisation consistency on language skills. However, 26 of 31 (84%) of individuals with inconsistent lateralisation were in the disorder group, compared to 41 of 73 (56%) of those with consistent lateralisation, a difference that was higher than would be expected by chance. The developmental disorder group also demonstrated weaker correlations between laterality indices across pairs of tasks. In summary, although the data did not support the hypothesis that inconsistent language lateralisation is a major cause of poor language skills, the results suggested that some subtypes of language disorder are associated with inefficient distribution of language functions between hemispheres. Inconsistent lateralisation could be a causal factor in the aetiology of language disorder, or may arise in some cases as the consequence of developmental disorder, possibly reflective of compensatory reorganisation.

Feature distinctiveness effects in language acquisition and lexical processing: Insights from megastudies

Semantic features are central to many influential theories of word meaning and semantic memory, but new methods of quantifying the information embedded in feature production norms are needed to advance our understanding of semantic processing and language acquisition. This paper capitalized on databases of semantic feature production norms and age-of-acquisition ratings, and megastudies including the English Lexicon Project and the Calgary Semantic Decision Project, to examine the influence of feature distinctiveness on language acquisition, visual lexical decision, and semantic decision. A feature network of English words was constructed such that edges in the network represented feature distance, or dissimilarity, between words (i.e., Jaccard and Manhattan distances of probability distributions of features elicited for each pair of words), enabling us to quantify the relative feature distinctiveness of individual words relative to other words in the network. Words with greater feature distinctiveness tended to be acquired earlier. Regression analyses of megastudy data revealed that Manhattan feature distinctiveness inhibited performance on the visual lexical decision task, facilitated semantic decision performance for concrete concepts, and inhibited semantic decision performance for abstract concepts. These results demonstrate the importance of considering the structural properties of words embedded in a semantic feature space in order to increase our understanding of semantic processing and language acquisition.

Theta/delta coupling across cortical laminae contributes to semantic cognition

Rhythmic activity in populations of neurons is associated with cognitive and motor function. Our understanding of the neuronal mechanisms underlying these core brain functions has benefitted from demonstrations of cellular, synaptic, and network phenomena, leading to the generation of discrete rhythms at the local network level. However, discrete frequencies of rhythmic activity rarely occur alone. Despite this, little is known about why multiple rhythms are generated together or what mechanisms underlie their interaction to promote brain function. One overarching theory is that different temporal scales of rhythmic activity correspond to communication between brain regions separated by different spatial scales. To test this, we quantified the cross-frequency interactions between two dominant rhythms—theta and delta activity—manifested during magnetoencephalography recordings of subjects performing a word-pair semantic decision task. Semantic processing has been suggested to involve the formation of functional links between anatomically disparate neuronal populations over a range of spatial scales, and a distributed network was manifest in the profile of theta-delta coupling seen. Furthermore, differences in the pattern of theta-delta coupling significantly correlated with semantic outcome. Using an established experimental model of concurrent delta and theta rhythms in neocortex, we show that these outcome-dependent dynamics could be reproduced in a manner determined by the strength of cholinergic neuromodulation. Theta-delta coupling correlated with discrete neuronal activity motifs segregated by the cortical layer, neuronal intrinsic properties, and long-range axonal targets. Thus, the model suggested that local, interlaminar neocortical theta-delta coupling may serve to coordinate both cortico-cortical and cortico-subcortical computations during distributed network activity. NEW & NOTEWORTHY Here, we show, for the first time, that a network of spatially distributed brain regions can be revealed by cross-frequency coupling between delta and theta frequencies in subjects using magnetoencephalography recording during a semantic decision task. A biological model of this cross-frequency coupling suggested an interlaminar, cell-specific division of labor within the neocortex may serve to route the flow of cortico-cortical and cortico-subcortical information to promote such spatially distributed, functional networks.